<?xml version="1.0" encoding="US-ASCII"?>
<!-- Generated by CompSci Transform (tm) - http://www.compsciresources.com -->
<!-- Created: Wed Aug 13 16:20:26 UTC 2025 -->
<linkbase xmlns="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:xbrldt="http://xbrl.org/2005/xbrldt">
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ConsolidatedBalanceSheet" roleURI="http://www.FreedomAcquisitionICorp.com/role/ConsolidatedBalanceSheet"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ConsolidatedBalanceSheet_Parentheticals" roleURI="http://www.FreedomAcquisitionICorp.com/role/ConsolidatedBalanceSheet_Parentheticals"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ConsolidatedIncomeStatement" roleURI="http://www.FreedomAcquisitionICorp.com/role/ConsolidatedIncomeStatement"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ShareholdersEquityType2or3" roleURI="http://www.FreedomAcquisitionICorp.com/role/ShareholdersEquityType2or3"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ConsolidatedCashFlow" roleURI="http://www.FreedomAcquisitionICorp.com/role/ConsolidatedCashFlow"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_Organization" roleURI="http://www.FreedomAcquisitionICorp.com/role/Organization"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SummaryofSignificantAccountingPolicies" roleURI="http://www.FreedomAcquisitionICorp.com/role/SummaryofSignificantAccountingPolicies"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BusinessCombination" roleURI="http://www.FreedomAcquisitionICorp.com/role/BusinessCombination"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_FairValueMeasurements" roleURI="http://www.FreedomAcquisitionICorp.com/role/FairValueMeasurements"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_OtherIntangibleAssets" roleURI="http://www.FreedomAcquisitionICorp.com/role/OtherIntangibleAssets"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_AccruedExpensesandOtherCurrentLiabilities" roleURI="http://www.FreedomAcquisitionICorp.com/role/AccruedExpensesandOtherCurrentLiabilities"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_OtherExpenseIncomeNet" roleURI="http://www.FreedomAcquisitionICorp.com/role/OtherExpenseIncomeNet"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_CapitalStock" roleURI="http://www.FreedomAcquisitionICorp.com/role/CapitalStock"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BorrowingsandDerivativeLiabilities" roleURI="http://www.FreedomAcquisitionICorp.com/role/BorrowingsandDerivativeLiabilities"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SAFEAgreements" roleURI="http://www.FreedomAcquisitionICorp.com/role/SAFEAgreements"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_StockBasedCompensation" roleURI="http://www.FreedomAcquisitionICorp.com/role/StockBasedCompensation"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_CommitmentsandContingencies" roleURI="http://www.FreedomAcquisitionICorp.com/role/CommitmentsandContingencies"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_IncomeTaxes" roleURI="http://www.FreedomAcquisitionICorp.com/role/IncomeTaxes"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BasicandDilutedNetLossPerShare" roleURI="http://www.FreedomAcquisitionICorp.com/role/BasicandDilutedNetLossPerShare"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SegmentInformation" roleURI="http://www.FreedomAcquisitionICorp.com/role/SegmentInformation"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_RelatedPartyTransactions" roleURI="http://www.FreedomAcquisitionICorp.com/role/RelatedPartyTransactions"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SubsequentEvents" roleURI="http://www.FreedomAcquisitionICorp.com/role/SubsequentEvents"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_AccountingPoliciesByPolicy" roleURI="http://www.FreedomAcquisitionICorp.com/role/AccountingPoliciesByPolicy"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SummaryofSignificantAccountingPoliciesTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/SummaryofSignificantAccountingPoliciesTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BusinessCombinationTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/BusinessCombinationTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_FairValueMeasurementsTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/FairValueMeasurementsTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_OtherIntangibleAssetsTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/OtherIntangibleAssetsTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_AccruedExpensesandOtherCurrentLiabilitiesTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/AccruedExpensesandOtherCurrentLiabilitiesTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_OtherExpenseIncomeNetTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/OtherExpenseIncomeNetTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_CapitalStockTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/CapitalStockTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BorrowingsandDerivativeLiabilitiesTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/BorrowingsandDerivativeLiabilitiesTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_StockBasedCompensationTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/StockBasedCompensationTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_CommitmentsandContingenciesTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/CommitmentsandContingenciesTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BasicandDilutedNetLossPerShareTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/BasicandDilutedNetLossPerShareTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SegmentInformationTables" roleURI="http://www.FreedomAcquisitionICorp.com/role/SegmentInformationTables"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofReconcilesCashCashEquivalentsandRestrictedCashTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofReconcilesCashCashEquivalentsandRestrictedCashTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofAllowanceforCreditLossesTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofAllowanceforCreditLossesTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofContractAssetsandContractLiabilitiesBalancesTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofContractAssetsandContractLiabilitiesBalancesTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofRevenueRecognizedTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofRevenueRecognizedTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofProvisionalFairValueofIdentifiableAssetsAcquiredandLiabilitiesAssumedTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofProvisionalFairValueofIdentifiableAssetsAcquiredandLiabilitiesAssumedTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofDerivativeLiabilityValuationInputsTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofDerivativeLiabilityValuationInputsTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofMeasuredatFairValueTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofMeasuredatFairValueTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofOtherIntangibleAssetswithFiniteUsefulLivesTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofOtherIntangibleAssetswithFiniteUsefulLivesTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofAccruedExpensesandOtherCurrentLiabilitiesTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofAccruedExpensesandOtherCurrentLiabilitiesTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofOtherExpenseIncomeNetTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofOtherExpenseIncomeNetTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofReservedSharesofCommonStockTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofReservedSharesofCommonStockTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofCommonStockforOutstandingWarrantsTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofCommonStockforOutstandingWarrantsTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofBorrowingsandDerivativeLiabilitiesTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofBorrowingsandDerivativeLiabilitiesTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofFairValueoftheDerivativeLiabilityTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofFairValueoftheDerivativeLiabilityTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofContingentInterestPayableTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofContingentInterestPayableTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofInterestExpenseandAmortizationofDebtDiscountCostTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofInterestExpenseandAmortizationofDebtDiscountCostTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofStockOptionActivityTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofStockOptionActivityTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofRSUActivityTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofRSUActivityTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofStockBasedCompensationExpenseTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofStockBasedCompensationExpenseTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofWarrantyProvisionTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofWarrantyProvisionTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofBasicandDilutedNetLossPerShareTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofBasicandDilutedNetLossPerShareTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofPotentialCommonSharesOutstandingthatwereExcludedfromtheComputationofDilutedNetLossPerShareofCommonStockTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofPotentialCommonSharesOutstandingthatwereExcludedfromtheComputationofDilutedNetLossPerShareofCommonStockTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofFinancialPerformancethroughReportableSegmentsTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofFinancialPerformancethroughReportableSegmentsTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_ScheduleofAssetsbySegmentTable" roleURI="http://www.FreedomAcquisitionICorp.com/role/ScheduleofAssetsbySegmentTable"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_OrganizationDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/OrganizationDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SummaryofSignificantAccountingPoliciesDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/SummaryofSignificantAccountingPoliciesDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BusinessCombinationDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/BusinessCombinationDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_FairValueMeasurementsDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/FairValueMeasurementsDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_OtherIntangibleAssetsDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/OtherIntangibleAssetsDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_AccruedExpensesandOtherCurrentLiabilitiesDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/AccruedExpensesandOtherCurrentLiabilitiesDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_OtherExpenseIncomeNetDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/OtherExpenseIncomeNetDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_CapitalStockDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/CapitalStockDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BorrowingsandDerivativeLiabilitiesDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/BorrowingsandDerivativeLiabilitiesDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SAFEAgreementsDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/SAFEAgreementsDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_StockBasedCompensationDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/StockBasedCompensationDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_CommitmentsandContingenciesDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/CommitmentsandContingenciesDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_IncomeTaxesDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/IncomeTaxesDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_BasicandDilutedNetLossPerShareDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/BasicandDilutedNetLossPerShareDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SegmentInformationDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/SegmentInformationDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_RelatedPartyTransactionsDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/RelatedPartyTransactionsDetails"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#cslr_r_SubsequentEventsDetails" roleURI="http://www.FreedomAcquisitionICorp.com/role/SubsequentEventsDetails"/>
  <roleRef xlink:type="simple" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd#eedm" roleURI="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists"/>
  <roleRef xlink:type="simple" xlink:href="cslr-20250629.xsd#DocumentAndEntityInformation" roleURI="http://www.FreedomAcquisitionICorp.com/role/DocumentAndEntityInformation"/>
  <arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default"/>
  <arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain"/>
  <arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension"/>
  <arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member"/>
  <arcroleRef xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" arcroleURI="http://xbrl.org/int/dim/arcrole/all"/>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ConsolidatedBalanceSheet" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_StatementLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StatementTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_StatementTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsReceivableNetCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_AccountsReceivableNetCurrent" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InventoryNet" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_InventoryNet" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_PrepaidExpenseAndOtherAssetsCurrent" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNetCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_ContractWithCustomerAssetNetCurrent" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AssetsCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_AssetsCurrent" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RestrictedCashNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_RestrictedCashNoncurrent" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PropertyPlantAndEquipmentNet" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_PropertyPlantAndEquipmentNet" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OperatingLeaseRightOfUseAsset" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseRightOfUseAsset"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_OperatingLeaseRightOfUseAsset" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_FiniteLivedIntangibleAssetsNet" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Goodwill" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Goodwill"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_Goodwill" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherAssetsNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_OtherAssetsNoncurrent" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Assets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_Assets" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_AccountsPayableCurrent" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NotesPayableCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NotesPayableCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_NotesPayableCurrent" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ContractWithCustomerLiabilityCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiabilityCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_ContractWithCustomerLiabilityCurrent" order="16" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SAFEAgreementsCurrent" xlink:href="cslr-20250629.xsd#cslr_SAFEAgreementsCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="cslr_SAFEAgreementsCurrent" order="17" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ForwardPurchaseAgreementLiabilitiesWithRelatedParties" xlink:href="cslr-20250629.xsd#cslr_ForwardPurchaseAgreementLiabilitiesWithRelatedParties"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="cslr_ForwardPurchaseAgreementLiabilitiesWithRelatedParties" order="18" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeLiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilitiesCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_DerivativeLiabilitiesCurrent" order="19" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_LiabilitiesCurrent" order="20" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProductWarrantyAccrualNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyAccrualNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_ProductWarrantyAccrualNoncurrent" order="21" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeLiabilitiesNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilitiesNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_DerivativeLiabilitiesNoncurrent" order="22" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ContractWithCustomerLiabilityNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiabilityNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_ContractWithCustomerLiabilityNoncurrent" order="23" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LongTermNotesPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermNotesPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_LongTermNotesPayable" order="24" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherNotesPayableCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNotesPayableCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_OtherNotesPayableCurrent" order="25" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_OperatingLeaseLiabilityNoncurrent" order="26" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherLiabilitiesNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilitiesNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_OtherLiabilitiesNoncurrent" order="27" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Liabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Liabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_Liabilities" order="28" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommitmentsAndContingencies" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingencies"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_CommitmentsAndContingencies" order="29" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_CommonStockValue" order="30" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AdditionalPaidInCapitalCommonStock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalCommonStock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_AdditionalPaidInCapitalCommonStock" order="31" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" order="32" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit" order="33" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockholdersEquity" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StockholdersEquity" order="34" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesAndStockholdersEquity"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_LiabilitiesAndStockholdersEquity" order="35" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ConsolidatedBalanceSheet_Parentheticals" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_StatementOfFinancialPositionAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOfFinancialPositionAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_CommonStockParOrStatedValuePerShare" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockSharesAuthorized" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_CommonStockSharesAuthorized" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockSharesIssued" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_CommonStockSharesIssued" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockSharesOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfFinancialPositionAbstract" xlink:to="us-gaap_CommonStockSharesOutstanding" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ConsolidatedIncomeStatement" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeStatementAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Revenues" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_Revenues" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CostOfRevenue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_CostOfRevenue" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_GrossProfit" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GrossProfit"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_GrossProfit" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SalesCommissionsAndFees" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalesCommissionsAndFees"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_SalesCommissionsAndFees" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MarketingExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MarketingExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_MarketingExpense" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_GeneralAndAdministrativeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_GeneralAndAdministrativeExpense" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OperatingExpenses" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingExpenses"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_OperatingExpenses" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OperatingIncomeLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_OperatingIncomeLoss" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestExpenseNonoperating" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseNonoperating"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_InterestExpenseNonoperating" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InvestmentIncomeInterest" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentIncomeInterest"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_InvestmentIncomeInterest" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherNonoperatingIncomeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_OtherNonoperatingIncomeExpense" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NonoperatingIncomeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NonoperatingIncomeExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_NonoperatingIncomeExpense" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeTaxExpenseBenefit" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeTaxExpenseBenefit" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperations" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperations"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeLossFromContinuingOperations" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalNetOfTax" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalNetOfTax"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_DiscontinuedOperationProvisionForLossGainOnDisposalNetOfTax" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity" order="16" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_NetIncomeLoss" order="17" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" order="18" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ComprehensiveIncomeNetOfTax" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ComprehensiveIncomeNetOfTax"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_ComprehensiveIncomeNetOfTax" order="19" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperationsPerBasicShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsPerBasicShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeLossFromContinuingOperationsPerBasicShare" order="20" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare" order="21" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare" order="22" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare" order="23" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EarningsPerShareBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_EarningsPerShareBasic" order="24" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EarningsPerShareDiluted" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_EarningsPerShareDiluted" order="25" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" order="26" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" order="27" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_LossGainOnRemeasurementOfDerivativeLiabilitiesNote9BorrowingsAndDerivativeLiabilit" xlink:href="cslr-20250629.xsd#cslr_LossGainOnRemeasurementOfDerivativeLiabilitiesNote9BorrowingsAndDerivativeLiabilit"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="cslr_LossGainOnRemeasurementOfDerivativeLiabilitiesNote9BorrowingsAndDerivativeLiabilit" order="28" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_GainlossDueToChangeInFairValueOfForwardPurchaseAgreements" xlink:href="cslr-20250629.xsd#cslr_GainlossDueToChangeInFairValueOfForwardPurchaseAgreements"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="cslr_GainlossDueToChangeInFairValueOfForwardPurchaseAgreements" order="29" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_LossOnConversionOfSAFEAgreementsToCommonStockinShares" xlink:href="cslr-20250629.xsd#cslr_LossOnConversionOfSAFEAgreementsToCommonStockinShares"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="cslr_LossOnConversionOfSAFEAgreementsToCommonStockinShares" order="30" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_LossGainDueToChangeInFairValueOfCarlyleWarrants" xlink:href="cslr-20250629.xsd#cslr_LossGainDueToChangeInFairValueOfCarlyleWarrants"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="cslr_LossGainDueToChangeInFairValueOfCarlyleWarrants" order="31" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NoncashIncomeDueToRelatedParties" xlink:href="cslr-20250629.xsd#cslr_NoncashIncomeDueToRelatedParties"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementAbstract" xlink:to="cslr_NoncashIncomeDueToRelatedParties" order="32" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ShareholdersEquityType2or3" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_StatementLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StatementTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementEquityComponentsAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_StatementTable" xlink:to="us-gaap_StatementEquityComponentsAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_CommonStockMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AdditionalPaidInCapitalMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_AdditionalPaidInCapitalMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RetainedEarningsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_RetainedEarningsMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_AccumulatedOtherComprehensiveIncomeMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockSharesOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_CommonStockSharesOutstanding" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockholdersEquity" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquity"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StockholdersEquity" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardGross" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_StockIssuedDutringPeriodValueExerciseOfCommonStockWarrants" xlink:href="cslr-20250629.xsd#cslr_StockIssuedDutringPeriodValueExerciseOfCommonStockWarrants"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="cslr_StockIssuedDutringPeriodValueExerciseOfCommonStockWarrants" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_NetIncomeLoss" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfUnits" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfUnits"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodValueConversionOfUnits" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentTax" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_StockIssuedDuringPeriodSharesExerciseOfCommonStockWarrantsinShares" xlink:href="cslr-20250629.xsd#cslr_StockIssuedDuringPeriodSharesExerciseOfCommonStockWarrantsinShares"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementLineItems" xlink:to="cslr_StockIssuedDuringPeriodSharesExerciseOfCommonStockWarrantsinShares" order="13" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ConsolidatedCashFlow" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_StatementOfCashFlowsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementOfCashFlowsAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLoss"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_NetIncomeLoss" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperations" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperations"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncomeLossFromContinuingOperations" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensation" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensation"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_ShareBasedCompensation" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PaidInKindInterest" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaidInKindInterest"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_PaidInKindInterest" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NonCashLeaseExpense" xlink:href="cslr-20250629.xsd#cslr_NonCashLeaseExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_NonCashLeaseExpense" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DepreciationDepletionAndAmortization" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_DepreciationDepletionAndAmortization" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProvisionForDoubtfulAccounts" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProvisionForDoubtfulAccounts"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_ProvisionForDoubtfulAccounts" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InventoryWriteDown" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InventoryWriteDown"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_InventoryWriteDown" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInFairValueOfSAFEAgreements" xlink:href="cslr-20250629.xsd#cslr_ChangeInFairValueOfSAFEAgreements"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_ChangeInFairValueOfSAFEAgreements" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInFairValueOfForwardPurchaseAgreementLiabilities" xlink:href="cslr-20250629.xsd#cslr_ChangeInFairValueOfForwardPurchaseAgreementLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_ChangeInFairValueOfForwardPurchaseAgreementLiabilities" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_FairValueOfDerivativeLiabilities" xlink:href="cslr-20250629.xsd#cslr_FairValueOfDerivativeLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_FairValueOfDerivativeLiabilities" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AmortizationOfFinancingCosts" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCosts"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_AmortizationOfFinancingCosts" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAdjustmentOfWarrants" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAdjustmentOfWarrants"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_FairValueAdjustmentOfWarrants" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherNoncashIncomeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNoncashIncomeExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_OtherNoncashIncomeExpense" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AssetImpairmentCharges" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetImpairmentCharges"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_AssetImpairmentCharges" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AccretionOfDebtInCSSolisRelatedParty" xlink:href="cslr-20250629.xsd#cslr_AccretionOfDebtInCSSolisRelatedParty"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_AccretionOfDebtInCSSolisRelatedParty" order="16" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_LossOnConversionOfSAFEAgreementsToSharesOfCommonStock" xlink:href="cslr-20250629.xsd#cslr_LossOnConversionOfSAFEAgreementsToSharesOfCommonStock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_LossOnConversionOfSAFEAgreementsToSharesOfCommonStock" order="17" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherNoncashExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNoncashExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_OtherNoncashExpense" order="18" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInAccountsReceivable" order="19" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInInventories" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInInventories"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInInventories" order="20" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInContractWithCustomerAsset" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerAsset"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInContractWithCustomerAsset" order="21" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" order="22" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOtherNoncurrentAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInOtherNoncurrentAssets" order="23" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccountsPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInAccountsPayable" order="24" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInAccruedLiabilitiesAndOtherOperatingLiabilities" order="25" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInOperatingLeaseLiability" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInOperatingLeaseLiability"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInOperatingLeaseLiability" order="26" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncreaseDecreaseInContractWithCustomerLiability" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncreaseDecreaseInContractWithCustomerLiability" order="27" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivities" order="28" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PaymentsForSoftware" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsForSoftware"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_PaymentsForSoftware" order="29" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInInvestingActivities" order="30" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProceedsFromNotesPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromNotesPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_ProceedsFromNotesPayable" order="31" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RepaymentsOfNotesPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RepaymentsOfNotesPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_RepaymentsOfNotesPayable" order="32" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinanceLeasePrincipalPayments" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeasePrincipalPayments"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_FinanceLeasePrincipalPayments" order="33" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProceedsFromStockOptionsExercised" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromStockOptionsExercised"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_ProceedsFromStockOptionsExercised" order="34" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProceedsFromWarrantExercises" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromWarrantExercises"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_ProceedsFromWarrantExercises" order="35" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_InvestorFinancingDepositRelatedParty" xlink:href="cslr-20250629.xsd#cslr_InvestorFinancingDepositRelatedParty"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_InvestorFinancingDepositRelatedParty" order="36" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ProceedsFromIssuanceOfSAFEAgreements" xlink:href="cslr-20250629.xsd#cslr_ProceedsFromIssuanceOfSAFEAgreements"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_ProceedsFromIssuanceOfSAFEAgreements" order="37" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInFinancingActivities" order="38" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" order="39" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" order="40" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" order="41" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestPaidNet" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestPaidNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_InterestPaidNet" order="42" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeTaxesPaidNet" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxesPaidNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_IncomeTaxesPaidNet" order="43" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ConversionOfSAFEAgreementsToSharesOfCommonStockWithRelatedParty" xlink:href="cslr-20250629.xsd#cslr_ConversionOfSAFEAgreementsToSharesOfCommonStockWithRelatedParty"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_ConversionOfSAFEAgreementsToSharesOfCommonStockWithRelatedParty" order="44" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_MeasurementPeriodAdjustmentToIncreaseGoodwillDueToADecreaseInAcquiredFairValueOfI" xlink:href="cslr-20250629.xsd#cslr_MeasurementPeriodAdjustmentToIncreaseGoodwillDueToADecreaseInAcquiredFairValueOfI"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="cslr_MeasurementPeriodAdjustmentToIncreaseGoodwillDueToADecreaseInAcquiredFairValueOfI" order="45" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/Organization" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SummaryofSignificantAccountingPolicies" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AccountingPoliciesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SignificantAccountingPoliciesTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SignificantAccountingPoliciesTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_SignificantAccountingPoliciesTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BusinessCombination" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationsAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationsAbstract" xlink:to="us-gaap_BusinessCombinationDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/FairValueMeasurements" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueDisclosuresAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueDisclosuresAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueDisclosuresTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueDisclosuresTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueDisclosuresAbstract" xlink:to="us-gaap_FairValueDisclosuresTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/OtherIntangibleAssets" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IntangibleAssetsDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IntangibleAssetsDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:to="us-gaap_IntangibleAssetsDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/AccruedExpensesandOtherCurrentLiabilities" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:to="us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/OtherExpenseIncomeNet" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_OtherIncomeAndExpensesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherIncomeAndExpensesAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherIncomeAndExpensesAbstract" xlink:to="us-gaap_OtherIncomeAndOtherExpenseDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/CapitalStock" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfStockDisclosuresAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDisclosuresAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockDisclosuresAbstract" xlink:to="us-gaap_StockholdersEquityNoteDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BorrowingsandDerivativeLiabilities" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DebtDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubordinatedBorrowingsDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubordinatedBorrowingsDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtDisclosureAbstract" xlink:to="us-gaap_SubordinatedBorrowingsDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SAFEAgreements" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_CollateralizedAgreementsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollateralizedAgreementsAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CollaborativeArrangementDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollaborativeArrangementDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CollateralizedAgreementsAbstract" xlink:to="us-gaap_CollaborativeArrangementDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/StockBasedCompensation" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharebasedCompensationAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharebasedCompensationAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StockIssuedDuringPeriodSharebasedCompensationAbstract" xlink:to="us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/CommitmentsandContingencies" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:to="us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/IncomeTaxes" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeTaxDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeTaxDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeTaxDisclosureAbstract" xlink:to="us-gaap_IncomeTaxDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BasicandDilutedNetLossPerShare" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_EarningsPerShareAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EarningsPerShareTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EarningsPerShareAbstract" xlink:to="us-gaap_EarningsPerShareTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SegmentInformation" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentReportingAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentReportingDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingAbstract" xlink:to="us-gaap_SegmentReportingDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/RelatedPartyTransactions" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyTransactionsAbstract" xlink:to="us-gaap_RelatedPartyTransactionsDisclosureTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SubsequentEvents" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_SubsequentEventsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventsAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubsequentEventsTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventsTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventsAbstract" xlink:to="us-gaap_SubsequentEventsTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/AccountingPoliciesByPolicy" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AccountingPoliciesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BasisOfAccountingPolicyPolicyTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_BasisOfAccountingPolicyPolicyTextBlock" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_CashAndCashEquivalentsPolicyTextBlock" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_EstimatedCreditLossesPolicyTextBlock" xlink:href="cslr-20250629.xsd#cslr_EstimatedCreditLossesPolicyTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="cslr_EstimatedCreditLossesPolicyTextBlock" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ContractAssetsAndContractLiabilitiesPolicyTextBlock" xlink:href="cslr-20250629.xsd#cslr_ContractAssetsAndContractLiabilitiesPolicyTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="cslr_ContractAssetsAndContractLiabilitiesPolicyTextBlock" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RevenueFromContractWithCustomerPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerPolicyTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_RevenueFromContractWithCustomerPolicyTextBlock" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PriorPeriodReclassificationAdjustmentDescription"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_PriorPeriodReclassificationAdjustmentDescription" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInRelatedPartiesPolicyTextBlock" xlink:href="cslr-20250629.xsd#cslr_ChangeInRelatedPartiesPolicyTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="cslr_ChangeInRelatedPartiesPolicyTextBlock" order="7" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SummaryofSignificantAccountingPoliciesTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AccountingPoliciesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountingPoliciesAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfCashAndCashEquivalentsTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfCashAndCashEquivalentsTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_ScheduleOfCashAndCashEquivalentsTableTextBlock" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_AccountsReceivableAllowanceForCreditLossTableTextBlock" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ScheduleOfContractAssetsAndContractLiabilitiesTableTextBlock" xlink:href="cslr-20250629.xsd#cslr_ScheduleOfContractAssetsAndContractLiabilitiesTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="cslr_ScheduleOfContractAssetsAndContractLiabilitiesTableTextBlock" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountingPoliciesAbstract" xlink:to="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTextBlock" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BusinessCombinationTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationsAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationsAbstract" xlink:to="us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/FairValueMeasurementsTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueDisclosuresAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueDisclosuresAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueDisclosuresAbstract" xlink:to="us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueDisclosuresAbstract" xlink:to="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTextBlock" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueDisclosuresAbstract" xlink:to="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTableTextBlock" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringAndNonrecurringBasisTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringAndNonrecurringBasisTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueDisclosuresAbstract" xlink:to="us-gaap_FairValueAssetsMeasuredOnRecurringAndNonrecurringBasisTableTextBlock" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/OtherIntangibleAssetsTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:to="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/AccruedExpensesandOtherCurrentLiabilitiesTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:to="us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/OtherExpenseIncomeNetTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_OtherIncomeAndExpensesAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherIncomeAndExpensesAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherIncomeAndExpensesAbstract" xlink:to="us-gaap_ScheduleOfOtherNonoperatingIncomeExpenseTableTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/CapitalStockTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfStockDisclosuresAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDisclosuresAbstract"/>
    <loc xlink:type="locator" xlink:label="cslr_ScheduleOfReservedSharesOfCommonStockTableTextBlock" xlink:href="cslr-20250629.xsd#cslr_ScheduleOfReservedSharesOfCommonStockTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockDisclosuresAbstract" xlink:to="cslr_ScheduleOfReservedSharesOfCommonStockTableTextBlock" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockDisclosuresAbstract" xlink:to="us-gaap_ScheduleOfStockholdersEquityNoteWarrantsOrRightsTextBlock" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BorrowingsandDerivativeLiabilitiesTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DebtDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfDebtTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfDebtTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtDisclosureAbstract" xlink:to="us-gaap_ScheduleOfDebtTableTextBlock" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtDisclosureAbstract" xlink:to="us-gaap_ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ScheduleOfContingentInterestPayableTableTextBlock" xlink:href="cslr-20250629.xsd#cslr_ScheduleOfContingentInterestPayableTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtDisclosureAbstract" xlink:to="cslr_ScheduleOfContingentInterestPayableTableTextBlock" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ScheduleOfInterestExpenseAndAmortizationOfDebtDiscountCostTableTextBlock" xlink:href="cslr-20250629.xsd#cslr_ScheduleOfInterestExpenseAndAmortizationOfDebtDiscountCostTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtDisclosureAbstract" xlink:to="cslr_ScheduleOfInterestExpenseAndAmortizationOfDebtDiscountCostTableTextBlock" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/StockBasedCompensationTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharebasedCompensationAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharebasedCompensationAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StockIssuedDuringPeriodSharebasedCompensationAbstract" xlink:to="us-gaap_ScheduleOfShareBasedCompensationStockOptionsActivityTableTextBlock" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StockIssuedDuringPeriodSharebasedCompensationAbstract" xlink:to="us-gaap_ScheduleOfShareBasedCompensationRestrictedStockUnitsAwardActivityTableTextBlock" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_StockIssuedDuringPeriodSharebasedCompensationAbstract" xlink:to="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/CommitmentsandContingenciesTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:to="us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BasicandDilutedNetLossPerShareTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_EarningsPerShareAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EarningsPerShareAbstract" xlink:to="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EarningsPerShareAbstract" xlink:to="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SegmentInformationTables" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentReportingAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingAbstract" xlink:to="us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingAbstract" xlink:to="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofReconcilesCashCashEquivalentsandRestrictedCashTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RestrictedCashNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:to="us-gaap_RestrictedCashNoncurrent" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CashAndCashEquivalentsAtCarryingValueAbstract" xlink:to="us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofAllowanceforCreditLossesTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsReceivableNetAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsReceivableNetAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsReceivableNetAbstract" xlink:to="us-gaap_AllowanceForDoubtfulAccountsReceivable" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProvisionForOtherCreditLosses" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProvisionForOtherCreditLosses"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsReceivableNetAbstract" xlink:to="us-gaap_ProvisionForOtherCreditLosses" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableRecoveries" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableRecoveries"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsReceivableNetAbstract" xlink:to="us-gaap_AllowanceForDoubtfulAccountsReceivableRecoveries" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofContractAssetsandContractLiabilitiesBalancesTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNetCurrentAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ContractWithCustomerAssetNetCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerAssetNetCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ContractWithCustomerAssetNetCurrentAbstract" xlink:to="us-gaap_ContractWithCustomerAssetNetCurrent" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ContractWithCustomerLiability" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ContractWithCustomerLiability"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ContractWithCustomerAssetNetCurrentAbstract" xlink:to="us-gaap_ContractWithCustomerLiability" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofRevenueRecognizedTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DisaggregationOfRevenueLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_DisaggregationOfRevenueLineItems" xlink:to="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TimingOfTransferOfGoodOrServiceAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TimingOfTransferOfGoodOrServiceAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" xlink:to="us-gaap_TimingOfTransferOfGoodOrServiceAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TimingOfTransferOfGoodOrServiceDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TimingOfTransferOfGoodOrServiceDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_TimingOfTransferOfGoodOrServiceAxis" xlink:to="us-gaap_TimingOfTransferOfGoodOrServiceDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TimingOfTransferOfGoodOrServiceDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TimingOfTransferOfGoodOrServiceDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_TimingOfTransferOfGoodOrServiceAxis" xlink:to="us-gaap_TimingOfTransferOfGoodOrServiceDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_ProductOrServiceAxis" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" xlink:to="srt_ProductOrServiceAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_ProductsAndServicesDomain" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_ProductOrServiceAxis" xlink:to="srt_ProductsAndServicesDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_ProductsAndServicesDomain_0" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="srt_ProductOrServiceAxis" xlink:to="srt_ProductsAndServicesDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ResidentialSolarInstallationMember" xlink:href="cslr-20250629.xsd#cslr_ResidentialSolarInstallationMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_ProductsAndServicesDomain" xlink:to="cslr_ResidentialSolarInstallationMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NewHomesBusinessMember" xlink:href="cslr-20250629.xsd#cslr_NewHomesBusinessMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_ProductsAndServicesDomain" xlink:to="cslr_NewHomesBusinessMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TransferredOverTimeMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransferredOverTimeMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_TimingOfTransferOfGoodOrServiceDomain" xlink:to="us-gaap_TransferredOverTimeMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TransferredAtPointInTimeMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransferredAtPointInTimeMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_TimingOfTransferOfGoodOrServiceDomain" xlink:to="us-gaap_TransferredAtPointInTimeMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DisaggregationOfRevenueLineItems" xlink:to="us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Revenues" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DisaggregationOfRevenueLineItems" xlink:to="us-gaap_Revenues" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofProvisionalFairValueofIdentifiableAssetsAcquiredandLiabilitiesAssumedTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationSegmentAllocationLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_BusinessCombinationScheduleofProvisionalFairValueofIdentifiableAssetsAcquiredandLiabilitiesAssumedDetailsTable" xlink:href="cslr-20250629.xsd#cslr_BusinessCombinationScheduleofProvisionalFairValueofIdentifiableAssetsAcquiredandLiabilitiesAssumedDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="cslr_BusinessCombinationScheduleofProvisionalFairValueofIdentifiableAssetsAcquiredandLiabilitiesAssumedDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BusinessCombinationScheduleofProvisionalFairValueofIdentifiableAssetsAcquiredandLiabilitiesAssumedDetailsTable" xlink:to="us-gaap_BusinessAcquisitionAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_BusinessAcquisitionAxis" xlink:to="us-gaap_BusinessAcquisitionAcquireeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_BusinessAcquisitionAxis" xlink:to="us-gaap_BusinessAcquisitionAcquireeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ProvisionalFairValuesMember" xlink:href="cslr-20250629.xsd#cslr_ProvisionalFairValuesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessAcquisitionAcquireeDomain" xlink:to="cslr_ProvisionalFairValuesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_MeasurementPeriodAdjustmentMember" xlink:href="cslr-20250629.xsd#cslr_MeasurementPeriodAdjustmentMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessAcquisitionAcquireeDomain" xlink:to="cslr_MeasurementPeriodAdjustmentMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsOther" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightofuseAssets" xlink:href="cslr-20250629.xsd#cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightofuseAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseRightofuseAssets" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOtherNoncurrentAssets" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesDeferredRevenue" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesOther" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilities" xlink:href="cslr-20250629.xsd#cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedOperatingLeaseLiabilities" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesOther" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFairValueOfNetTangibleAssetsAcquired" xlink:href="cslr-20250629.xsd#cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFairValueOfNetTangibleAssetsAcquired"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="cslr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedFairValueOfNetTangibleAssetsAcquired" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentAssets" order="16" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_FairValueMeasurementsScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisDetailsTable" xlink:href="cslr-20250629.xsd#cslr_FairValueMeasurementsScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:to="cslr_FairValueMeasurementsScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisDetailsTable" xlink:to="us-gaap_FairValueByMeasurementFrequencyAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:to="us-gaap_FairValueMeasurementFrequencyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:to="us-gaap_FairValueMeasurementFrequencyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisDetailsTable" xlink:to="us-gaap_FairValueByFairValueHierarchyLevelAxis" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsScheduleofFinancialAssetsandLiabilitiesthatareMeasuredatFairValueonaRecurringBasisDetailsTable" xlink:to="us-gaap_ClassOfWarrantOrRightAxis" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueInputsLevel1Member" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel1Member" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueInputsLevel2Member" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel2Member" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueInputsLevel3Member" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel3Member" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_RestrictedCashMember" xlink:href="cslr-20250629.xsd#cslr_RestrictedCashMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_RestrictedCashMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesDerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesDerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_July2024NotesDerivativeLiabilityMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_September2024DerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_September2024DerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_September2024DerivativeLiabilityMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ForwardPurchaseAgreementLiabilitiesMember" xlink:href="cslr-20250629.xsd#cslr_ForwardPurchaseAgreementLiabilitiesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_ForwardPurchaseAgreementLiabilitiesMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PublicWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_PublicWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_PublicWarrantsMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PrivatePlacementWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_PrivatePlacementWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_PrivatePlacementWarrantsMember" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_WorkingCapitalWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_WorkingCapitalWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_WorkingCapitalWarrantsMember" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SAFEAgreementsMember" xlink:href="cslr-20250629.xsd#cslr_SAFEAgreementsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_SAFEAgreementsMember" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_September2024NotesDerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_September2024NotesDerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_September2024NotesDerivativeLiabilityMember" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsRecurringMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementFrequencyDomain" xlink:to="us-gaap_FairValueMeasurementsRecurringMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AssetsFairValueDisclosure" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:to="us-gaap_AssetsFairValueDisclosure" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosure" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialLiabilitiesFairValueDisclosure"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:to="us-gaap_FinancialLiabilitiesFairValueDisclosure" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofDerivativeLiabilityValuationInputsTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:to="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:to="us-gaap_MeasurementInputTypeAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_MeasurementInputTypeAxis" xlink:to="us-gaap_MeasurementInputTypeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_MeasurementInputTypeAxis" xlink:to="us-gaap_MeasurementInputTypeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationTable" xlink:to="us-gaap_DebtInstrumentAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_July2024NotesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_September2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_September2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_September2024NotesMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_MeasurementInputCouponRateMember" xlink:href="cslr-20250629.xsd#cslr_MeasurementInputCouponRateMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="cslr_MeasurementInputCouponRateMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_MeasurementInputConversionRateMember" xlink:href="cslr-20250629.xsd#cslr_MeasurementInputConversionRateMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="cslr_MeasurementInputConversionRateMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputConversionPriceMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputConversionPriceMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputConversionPriceMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputSharePriceMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputSharePriceMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputSharePriceMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputExpectedDividendRateMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputExpectedDividendRateMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputExpectedDividendRateMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeLiabilityMeasurementInput" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilityMeasurementInput"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems" xlink:to="us-gaap_DerivativeLiabilityMeasurementInput" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofMeasuredatFairValueTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xlink:to="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" xlink:to="us-gaap_MeasurementInputTypeAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_MeasurementInputTypeAxis" xlink:to="us-gaap_MeasurementInputTypeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_MeasurementInputTypeAxis" xlink:to="us-gaap_MeasurementInputTypeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeInstrumentRiskAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesTable" xlink:to="us-gaap_DerivativeInstrumentRiskAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeContractTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DerivativeInstrumentRiskAxis" xlink:to="us-gaap_DerivativeContractTypeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeContractTypeDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DerivativeInstrumentRiskAxis" xlink:to="us-gaap_DerivativeContractTypeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputExpectedTermMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputExpectedTermMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputExpectedTermMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputPriceVolatilityMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputPriceVolatilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputPriceVolatilityMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputRiskFreeInterestRateMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputRiskFreeInterestRateMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputRiskFreeInterestRateMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputExpectedDividendRateMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputExpectedDividendRateMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputExpectedDividendRateMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_MeasurementInputVWAPMember" xlink:href="cslr-20250629.xsd#cslr_MeasurementInputVWAPMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="cslr_MeasurementInputVWAPMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_MeasurementInputSimulationPeriodMember" xlink:href="cslr-20250629.xsd#cslr_MeasurementInputSimulationPeriodMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="cslr_MeasurementInputSimulationPeriodMember" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PrivatePlacementAndWorkingCapitalWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_PrivatePlacementAndWorkingCapitalWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativeContractTypeDomain" xlink:to="cslr_PrivatePlacementAndWorkingCapitalWarrantsMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ForwardPurchaseAgreementLiabilitiesMember" xlink:href="cslr-20250629.xsd#cslr_ForwardPurchaseAgreementLiabilitiesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativeContractTypeDomain" xlink:to="cslr_ForwardPurchaseAgreementLiabilitiesMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeLiabilityMeasurementInput" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilityMeasurementInput"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems" xlink:to="us-gaap_DerivativeLiabilityMeasurementInput" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_FairValueMeasurementsScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisDetailsTable" xlink:href="cslr-20250629.xsd#cslr_FairValueMeasurementsScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="cslr_FairValueMeasurementsScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisDetailsTable" xlink:to="us-gaap_FairValueByMeasurementFrequencyAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:to="us-gaap_FairValueMeasurementFrequencyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementFrequencyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FairValueByMeasurementFrequencyAxis" xlink:to="us-gaap_FairValueMeasurementFrequencyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisDetailsTable" xlink:to="us-gaap_FairValueByFairValueHierarchyLevelAxis" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueMeasurementsFairValueHierarchyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsScheduleofFinancialLiabilitiesthatwerenotMeasuredatFairValueonaNonRecurringBasisDetailsTable" xlink:to="us-gaap_ClassOfWarrantOrRightAxis" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueInputsLevel1Member" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel1Member" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueInputsLevel2Member" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel2Member" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueInputsLevel3Member" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="us-gaap_FairValueInputsLevel3Member" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_July2024NotesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_September2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_September2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_September2024NotesMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueMeasurementsNonrecurringMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueMeasurementsNonrecurringMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueMeasurementFrequencyDomain" xlink:to="us-gaap_FairValueMeasurementsNonrecurringMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_FinancialLiabilitiesCarryingValue" xlink:href="cslr-20250629.xsd#cslr_FinancialLiabilitiesCarryingValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="cslr_FinancialLiabilitiesCarryingValue" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LiabilitiesFairValueAdjustment" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesFairValueAdjustment"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="us-gaap_LiabilitiesFairValueAdjustment" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinancialLiabilitiesFairValueDisclosure" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialLiabilitiesFairValueDisclosure"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:to="us-gaap_FinancialLiabilitiesFairValueDisclosure" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofOtherIntangibleAssetswithFiniteUsefulLivesTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:to="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:to="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TrademarkBlueRavenSolarMember" xlink:href="cslr-20250629.xsd#cslr_TrademarkBlueRavenSolarMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="cslr_TrademarkBlueRavenSolarMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TrademarkSunPowerMember" xlink:href="cslr-20250629.xsd#cslr_TrademarkSunPowerMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="cslr_TrademarkSunPowerMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DevelopedTechnologyRightsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="us-gaap_DevelopedTechnologyRightsMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsGross" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:to="us-gaap_FiniteLivedIntangibleAssetsGross" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:to="us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FiniteLivedIntangibleAssetsNet" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:to="us-gaap_FiniteLivedIntangibleAssetsNet" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofAccruedExpensesandOtherCurrentLiabilitiesTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedLiabilitiesCurrentAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccruedEmployeeBenefitsCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedEmployeeBenefitsCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_AccruedEmployeeBenefitsCurrent" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccruedProfessionalFeesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedProfessionalFeesCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_AccruedProfessionalFeesCurrent" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AccruedExpensesInstallationCost" xlink:href="cslr-20250629.xsd#cslr_AccruedExpensesInstallationCost"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="cslr_AccruedExpensesInstallationCost" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AccruedLegalSettlements" xlink:href="cslr-20250629.xsd#cslr_AccruedLegalSettlements"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="cslr_AccruedLegalSettlements" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccruedIncomeTaxes" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccruedIncomeTaxes"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_AccruedIncomeTaxes" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AccruedRebateAndCredits" xlink:href="cslr-20250629.xsd#cslr_AccruedRebateAndCredits"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="cslr_AccruedRebateAndCredits" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OperatingLeaseLiabilityCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_OperatingLeaseLiabilityCurrent" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinanceLeaseLiabilityCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeaseLiabilityCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_FinanceLeaseLiabilityCurrent" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AccruedWarrantyCurrent" xlink:href="cslr-20250629.xsd#cslr_AccruedWarrantyCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="cslr_AccruedWarrantyCurrent" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_DeferredFinancingFees" xlink:href="cslr-20250629.xsd#cslr_DeferredFinancingFees"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="cslr_DeferredFinancingFees" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestPayableCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestPayableCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_InterestPayableCurrent" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDepositLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDepositLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_RelatedPartyDepositLiabilities" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherAccruedLiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherAccruedLiabilitiesCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_OtherAccruedLiabilitiesCurrent" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccruedLiabilitiesCurrentAbstract" xlink:to="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent" order="13" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofOtherExpenseIncomeNetTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpenseAbstract"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInFairValueOfDerivativeLiabilities" xlink:href="cslr-20250629.xsd#cslr_ChangeInFairValueOfDerivativeLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="cslr_ChangeInFairValueOfDerivativeLiabilities" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInFairValueOfForwardPurchasesAgreementLiabilities" xlink:href="cslr-20250629.xsd#cslr_ChangeInFairValueOfForwardPurchasesAgreementLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="cslr_ChangeInFairValueOfForwardPurchasesAgreementLiabilities" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInFairValueOfSAFEAgreementWithRelatedParty" xlink:href="cslr-20250629.xsd#cslr_ChangeInFairValueOfSAFEAgreementWithRelatedParty"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="cslr_ChangeInFairValueOfSAFEAgreementWithRelatedParty" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInFairValueOfFACTPublicPrivatePlacementAndWorkingCapitalWarrants" xlink:href="cslr-20250629.xsd#cslr_ChangeInFairValueOfFACTPublicPrivatePlacementAndWorkingCapitalWarrants"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="cslr_ChangeInFairValueOfFACTPublicPrivatePlacementAndWorkingCapitalWarrants" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInFairValueOfCarlyleWarrantsWithRelatedParty" xlink:href="cslr-20250629.xsd#cslr_ChangeInFairValueOfCarlyleWarrantsWithRelatedParty"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="cslr_ChangeInFairValueOfCarlyleWarrantsWithRelatedParty" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ChangeInFairValueOfRedeemableConvertiblePreferredStockWarrantLiability" xlink:href="cslr-20250629.xsd#cslr_ChangeInFairValueOfRedeemableConvertiblePreferredStockWarrantLiability"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="cslr_ChangeInFairValueOfRedeemableConvertiblePreferredStockWarrantLiability" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_LossOnConversionOfSAFEAgreementsToCommonStockWithRelatedParty" xlink:href="cslr-20250629.xsd#cslr_LossOnConversionOfSAFEAgreementsToCommonStockWithRelatedParty"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="cslr_LossOnConversionOfSAFEAgreementsToCommonStockWithRelatedParty" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_LossOnDiscontinuedSolariaBusinessAndOtherNet" xlink:href="cslr-20250629.xsd#cslr_LossOnDiscontinuedSolariaBusinessAndOtherNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="cslr_LossOnDiscontinuedSolariaBusinessAndOtherNet" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherNonoperatingIncomeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherNonoperatingIncomeExpenseAbstract" xlink:to="us-gaap_OtherNonoperatingIncomeExpense" order="8" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofReservedSharesofCommonStockTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="cslr_CapitalStockScheduleofReservedSharesofCommonStockDetailsLineItems" xlink:href="cslr-20250629.xsd#cslr_CapitalStockScheduleofReservedSharesofCommonStockDetailsLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_CapitalStockScheduleofReservedSharesofCommonStockDetailsTable" xlink:href="cslr-20250629.xsd#cslr_CapitalStockScheduleofReservedSharesofCommonStockDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="cslr_CapitalStockScheduleofReservedSharesofCommonStockDetailsLineItems" xlink:to="cslr_CapitalStockScheduleofReservedSharesofCommonStockDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementEquityComponentsAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_CapitalStockScheduleofReservedSharesofCommonStockDetailsTable" xlink:to="us-gaap_StatementEquityComponentsAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CommonStockWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_CommonStockWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="cslr_CommonStockWarrantsMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_EmployeeStockPurchasePlanMember" xlink:href="cslr-20250629.xsd#cslr_EmployeeStockPurchasePlanMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="cslr_EmployeeStockPurchasePlanMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_StockOptionsAndRSUsIssuedAndOutstandingMember" xlink:href="cslr-20250629.xsd#cslr_StockOptionsAndRSUsIssuedAndOutstandingMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="cslr_StockOptionsAndRSUsIssuedAndOutstandingMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_StockOptionsAndRSUsAuthorizedForFutureIssuanceMember" xlink:href="cslr-20250629.xsd#cslr_StockOptionsAndRSUsAuthorizedForFutureIssuanceMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="cslr_StockOptionsAndRSUsAuthorizedForFutureIssuanceMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SAFEAgreementsMember" xlink:href="cslr-20250629.xsd#cslr_SAFEAgreementsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="cslr_SAFEAgreementsMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ForwardPurchaseAgreementsMember" xlink:href="cslr-20250629.xsd#cslr_ForwardPurchaseAgreementsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="cslr_ForwardPurchaseAgreementsMember" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ConvertibleNotesMember" xlink:href="cslr-20250629.xsd#cslr_ConvertibleNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="cslr_ConvertibleNotesMember" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_CapitalStockScheduleofReservedSharesofCommonStockDetailsLineItems" xlink:to="us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofCommonStockforOutstandingWarrantsTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ClassOfWarrantOrRightTable" xlink:to="us-gaap_ClassOfWarrantOrRightAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PublicWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_PublicWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_PublicWarrantsMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PrivatePlacementWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_PrivatePlacementWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_PrivatePlacementWarrantsMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_WorkingCapitalWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_WorkingCapitalWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_WorkingCapitalWarrantsMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_LiabilityClassifiedWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_LiabilityClassifiedWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_LiabilityClassifiedWarrantsMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SeriesBWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_SeriesBWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_SeriesBWarrantsMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SeriesCWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_SeriesCWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_SeriesCWarrantsMember" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SeriesC1WarrantsMember" xlink:href="cslr-20250629.xsd#cslr_SeriesC1WarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_SeriesC1WarrantsMember" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SVBCommonStockWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_SVBCommonStockWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_SVBCommonStockWarrantsMember" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SVBCommonStockWarrantsOneMember" xlink:href="cslr-20250629.xsd#cslr_SVBCommonStockWarrantsOneMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_SVBCommonStockWarrantsOneMember" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PromissoryNoteCommonStockWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_PromissoryNoteCommonStockWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_PromissoryNoteCommonStockWarrantsMember" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2023CommonStockWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_July2023CommonStockWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_July2023CommonStockWarrantsMember" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CommonStockWarrantsIssuedIn2023Member" xlink:href="cslr-20250629.xsd#cslr_CommonStockWarrantsIssuedIn2023Member"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_CommonStockWarrantsIssuedIn2023Member" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AynaWarrantMember" xlink:href="cslr-20250629.xsd#cslr_AynaWarrantMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_AynaWarrantMember" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CantorWarrantMember" xlink:href="cslr-20250629.xsd#cslr_CantorWarrantMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_CantorWarrantMember" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_EquityClassifiedWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_EquityClassifiedWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_EquityClassifiedWarrantsMember" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PotentialSharesOfCommonStockMember" xlink:href="cslr-20250629.xsd#cslr_PotentialSharesOfCommonStockMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_PotentialSharesOfCommonStockMember" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockOptionExercisePriceIncrease" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockOptionExercisePriceIncrease"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="us-gaap_StockOptionExercisePriceIncrease" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ExpirationDate" xlink:href="cslr-20250629.xsd#cslr_ExpirationDate"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="cslr_ExpirationDate" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofBorrowingsandDerivativeLiabilitiesTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_SubordinatedBorrowingLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubordinatedBorrowingLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_BorrowingsandDerivativeLiabilitiesScheduleofBorrowingsandDerivativeLiabilitiesDetailsTable" xlink:href="cslr-20250629.xsd#cslr_BorrowingsandDerivativeLiabilitiesScheduleofBorrowingsandDerivativeLiabilitiesDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_SubordinatedBorrowingLineItems" xlink:to="cslr_BorrowingsandDerivativeLiabilitiesScheduleofBorrowingsandDerivativeLiabilitiesDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesScheduleofBorrowingsandDerivativeLiabilitiesDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesScheduleofBorrowingsandDerivativeLiabilitiesDetailsTable" xlink:to="us-gaap_DebtInstrumentAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_July2024NotesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesDerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesDerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_July2024NotesDerivativeLiabilityMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_JulyTwoThousandTwentyFourNotesRelatedPartyMember" xlink:href="cslr-20250629.xsd#cslr_JulyTwoThousandTwentyFourNotesRelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_JulyTwoThousandTwentyFourNotesRelatedPartyMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_JulyTwoThousandTwentyFourNotesDerivativeLiabilityRelatedPartyMember" xlink:href="cslr-20250629.xsd#cslr_JulyTwoThousandTwentyFourNotesDerivativeLiabilityRelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_JulyTwoThousandTwentyFourNotesDerivativeLiabilityRelatedPartyMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_September2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_September2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_September2024NotesMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityMember" order="5" xbrldt:closed="true"/>
<!-- [WMV6][oOhWlZUsD54ZCiFFzpWZZW7GD2QFl8QIqlMljXVlWA4s1ZEupECd1Pgk+f/gmV1ano6jxqb2ryFmJWadx4zn3f2uojBElyNTtssnP1FBAzOq6M0x5nrH38gRWJ56jYCbShV9neEaxcMw1Ck9t+R2LIHBT518NkBiqUM60ztjaU6i6syfp9AiQ40de4ccJtIpplQflOgelvW/pSmuruigOU31f7PeoeY7lM1KvmIfXBPE6K2BzAvt06Pym8RgxS2hZDDH95QSU0e6dx6+T6C/yxIHz/V5d2uyYIg0Da/VNLbOhSPhm3fMrixrQRDu7WKckXpbKX7tCriv7hQ8x0FbwgoVrHbOJYMm6/NawwqGxGy4h7gPmnXaKeRicxVMsOGt4uBYl8GmEf3Flk8lnzUwOqMgXPw+l2CtyUVOQz60/Sq8] CSR-->
    <loc xlink:type="locator" xlink:label="cslr_SeptemberTwoThousandTwentyFourNotesRelatedPartyMember" xlink:href="cslr-20250629.xsd#cslr_SeptemberTwoThousandTwentyFourNotesRelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_SeptemberTwoThousandTwentyFourNotesRelatedPartyMember" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityRelatedPartyMember" xlink:href="cslr-20250629.xsd#cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityRelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityRelatedPartyMember" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_LoansWithRelatedPartyMember" xlink:href="cslr-20250629.xsd#cslr_LoansWithRelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_LoansWithRelatedPartyMember" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NotesPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NotesPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubordinatedBorrowingLineItems" xlink:to="us-gaap_NotesPayable" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ConvertibleNotesPayableCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayableCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubordinatedBorrowingLineItems" xlink:to="us-gaap_ConvertibleNotesPayableCurrent" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ConvertibleLongTermNotesPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleLongTermNotesPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubordinatedBorrowingLineItems" xlink:to="us-gaap_ConvertibleLongTermNotesPayable" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NotesPayableCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NotesPayableCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubordinatedBorrowingLineItems" xlink:to="us-gaap_NotesPayableCurrent" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LongTermNotesPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermNotesPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubordinatedBorrowingLineItems" xlink:to="us-gaap_LongTermNotesPayable" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherLongTermNotesPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLongTermNotesPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubordinatedBorrowingLineItems" xlink:to="us-gaap_OtherLongTermNotesPayable" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LongTermDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LongTermDebt"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubordinatedBorrowingLineItems" xlink:to="us-gaap_LongTermDebt" order="6" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofFairValueoftheDerivativeLiabilityTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativesFairValueLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativesFairValueLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_DerivativesFairValueLineItems" xlink:to="us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinancialInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:to="us-gaap_FinancialInstrumentAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FinancialInstrumentAxis" xlink:to="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FinancialInstrumentAxis" xlink:to="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:to="us-gaap_DebtInstrumentAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember" xlink:href="cslr-20250629.xsd#cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember" xlink:href="cslr-20250629.xsd#cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="cslr_July2024NotesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesDerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesDerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="cslr_July2024NotesDerivativeLiabilityMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_September2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_September2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="cslr_September2024NotesMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_September2024NotesDerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_September2024NotesDerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="cslr_September2024NotesDerivativeLiabilityMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeLiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilitiesCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativesFairValueLineItems" xlink:to="us-gaap_DerivativeLiabilitiesCurrent" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentUnamortizedDiscount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativesFairValueLineItems" xlink:to="us-gaap_DebtInstrumentUnamortizedDiscount" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativesFairValueLineItems" xlink:to="us-gaap_DerivativeLiabilities" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofContingentInterestPayableTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DividendsPayableLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DividendsPayableLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_BorrowingsandDerivativeLiabilitiesScheduleofContingentInterestPayableDetailsTable" xlink:href="cslr-20250629.xsd#cslr_BorrowingsandDerivativeLiabilitiesScheduleofContingentInterestPayableDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_DividendsPayableLineItems" xlink:to="cslr_BorrowingsandDerivativeLiabilitiesScheduleofContingentInterestPayableDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeInstrumentRiskAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesScheduleofContingentInterestPayableDetailsTable" xlink:to="us-gaap_DerivativeInstrumentRiskAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeContractTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DerivativeInstrumentRiskAxis" xlink:to="us-gaap_DerivativeContractTypeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeContractTypeDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DerivativeInstrumentRiskAxis" xlink:to="us-gaap_DerivativeContractTypeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ContingentInterestPayableMember" xlink:href="cslr-20250629.xsd#cslr_ContingentInterestPayableMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativeContractTypeDomain" xlink:to="cslr_ContingentInterestPayableMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ContingentInterestPayableRelatedPartiesMember" xlink:href="cslr-20250629.xsd#cslr_ContingentInterestPayableRelatedPartiesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativeContractTypeDomain" xlink:to="cslr_ContingentInterestPayableRelatedPartiesMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ContingentInterestPayable" xlink:href="cslr-20250629.xsd#cslr_ContingentInterestPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DividendsPayableLineItems" xlink:to="cslr_ContingentInterestPayable" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofInterestExpenseandAmortizationofDebtDiscountCostTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="srt_InterestRateAndInterestDifferentialAnalysisLineItems" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_InterestRateAndInterestDifferentialAnalysisLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_BorrowingsandDerivativeLiabilitiesScheduleofInterestExpenseandAmortizationofDebtDiscountCostDetailsTable" xlink:href="cslr-20250629.xsd#cslr_BorrowingsandDerivativeLiabilitiesScheduleofInterestExpenseandAmortizationofDebtDiscountCostDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="srt_InterestRateAndInterestDifferentialAnalysisLineItems" xlink:to="cslr_BorrowingsandDerivativeLiabilitiesScheduleofInterestExpenseandAmortizationofDebtDiscountCostDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesScheduleofInterestExpenseandAmortizationofDebtDiscountCostDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesScheduleofInterestExpenseandAmortizationofDebtDiscountCostDetailsTable" xlink:to="us-gaap_DebtInstrumentAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember" xlink:href="cslr-20250629.xsd#cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember" xlink:href="cslr-20250629.xsd#cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestExpenseDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseDebt"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_InterestRateAndInterestDifferentialAnalysisLineItems" xlink:to="us-gaap_InterestExpenseDebt" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AmortizationOfFinancingCostsAndDiscounts" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_InterestRateAndInterestDifferentialAnalysisLineItems" xlink:to="us-gaap_AmortizationOfFinancingCostsAndDiscounts" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_InterestRateAndInterestDifferentialAnalysisLineItems" xlink:to="us-gaap_InterestExpense" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofStockOptionActivityTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_StockBasedCompensationScheduleofStockOptionActivityDetailsTable" xlink:href="cslr-20250629.xsd#cslr_StockBasedCompensationScheduleofStockOptionActivityDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="cslr_StockBasedCompensationScheduleofStockOptionActivityDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AwardTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_StockBasedCompensationScheduleofStockOptionActivityDetailsTable" xlink:to="us-gaap_AwardTypeAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_AwardTypeAxis" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_AwardTypeAxis" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockOptionMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockOptionMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="us-gaap_StockOptionMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingNumber" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageRemainingContractualTerm1" order="16" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableAggregateIntrinsicValue" order="17" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofRSUActivityTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_StockBasedCompensationScheduleofRSUActivityDetailsTable" xlink:href="cslr-20250629.xsd#cslr_StockBasedCompensationScheduleofRSUActivityDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="cslr_StockBasedCompensationScheduleofRSUActivityDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AwardTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_StockBasedCompensationScheduleofRSUActivityDetailsTable" xlink:to="us-gaap_AwardTypeAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_AwardTypeAxis" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_AwardTypeAxis" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RestrictedStockUnitsRSUMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="us-gaap_RestrictedStockUnitsRSUMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeituresWeightedAverageGrantDateFairValue" order="7" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofStockBasedCompensationExpenseTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeStatementLocationAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:to="us-gaap_IncomeStatementLocationAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeStatementLocationDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_IncomeStatementLocationAxis" xlink:to="us-gaap_IncomeStatementLocationDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeStatementLocationDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_IncomeStatementLocationAxis" xlink:to="us-gaap_IncomeStatementLocationDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CostOfSalesMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfSalesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_CostOfSalesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SellingAndMarketingExpenseMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpenseMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_SellingAndMarketingExpenseMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_GeneralAndAdministrativeExpenseMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AllocatedShareBasedCompensationExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:to="us-gaap_AllocatedShareBasedCompensationExpense" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofWarrantyProvisionTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_ProductWarrantyLiabilityLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyLiabilityLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProductWarrantyLiabilityTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyLiabilityTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_ProductWarrantyLiabilityLineItems" xlink:to="us-gaap_ProductWarrantyLiabilityTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BalanceSheetLocationAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ProductWarrantyLiabilityTable" xlink:to="us-gaap_BalanceSheetLocationAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BalanceSheetLocationDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_BalanceSheetLocationAxis" xlink:to="us-gaap_BalanceSheetLocationDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BalanceSheetLocationDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BalanceSheetLocationDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_BalanceSheetLocationAxis" xlink:to="us-gaap_BalanceSheetLocationDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_WarrantyProvisionCurrentMember" xlink:href="cslr-20250629.xsd#cslr_WarrantyProvisionCurrentMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BalanceSheetLocationDomain" xlink:to="cslr_WarrantyProvisionCurrentMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProductWarrantyAccrual" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyAccrual"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ProductWarrantyLiabilityLineItems" xlink:to="us-gaap_ProductWarrantyAccrual" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProductWarrantyAccrualWarrantiesIssued" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyAccrualWarrantiesIssued"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ProductWarrantyLiabilityLineItems" xlink:to="us-gaap_ProductWarrantyAccrualWarrantiesIssued" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProductWarrantyAccrualPayments" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyAccrualPayments"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ProductWarrantyLiabilityLineItems" xlink:to="us-gaap_ProductWarrantyAccrualPayments" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProductWarrantyAccrualClassifiedCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyAccrualClassifiedCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ProductWarrantyLiabilityLineItems" xlink:to="us-gaap_ProductWarrantyAccrualClassifiedCurrent" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProductWarrantyAccrualNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProductWarrantyAccrualNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ProductWarrantyLiabilityLineItems" xlink:to="us-gaap_ProductWarrantyAccrualNoncurrent" order="4" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofBasicandDilutedNetLossPerShareTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:href="cslr-20250629.xsd#cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersBasic" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersBasic"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersBasic" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ForwardPurchaseAgreementNetOfTax" xlink:href="cslr-20250629.xsd#cslr_ForwardPurchaseAgreementNetOfTax"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="cslr_ForwardPurchaseAgreementNetOfTax" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AdjustmentsToNumeratorForDilutedIncomelossPerShare" xlink:href="cslr-20250629.xsd#cslr_AdjustmentsToNumeratorForDilutedIncomelossPerShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="cslr_AdjustmentsToNumeratorForDilutedIncomelossPerShare" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersDiluted" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersDiluted"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_NetIncomeLossFromContinuingOperationsAvailableToCommonShareholdersDiluted" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersDiluted" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersDiluted"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_NetIncomeLossFromDiscontinuedOperationsAvailableToCommonShareholdersDiluted" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_IncomeTaxReconciliationForwardPurchaseAgreements" xlink:href="cslr-20250629.xsd#cslr_IncomeTaxReconciliationForwardPurchaseAgreements"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="cslr_IncomeTaxReconciliationForwardPurchaseAgreements" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperationsPerBasicShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsPerBasicShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_IncomeLossFromContinuingOperationsPerBasicShare" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EarningsPerShareBasic" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasic"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_EarningsPerShareBasic" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EarningsPerShareDiluted" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareDiluted"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="cslr_ScheduleOfBasicAndDilutedNetLossPerShareAbstract" xlink:to="us-gaap_EarningsPerShareDiluted" order="16" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofPotentialCommonSharesOutstandingthatwereExcludedfromtheComputationofDilutedNetLossPerShareofCommonStockTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:to="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:to="us-gaap_AntidilutiveSecuritiesNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AntidilutiveSecuritiesNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:to="us-gaap_AntidilutiveSecuritiesNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CommonStockWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_CommonStockWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="cslr_CommonStockWarrantsMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_StockOptionsAndRSUsIssuedAndOutstandingMember" xlink:href="cslr-20250629.xsd#cslr_StockOptionsAndRSUsIssuedAndOutstandingMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="cslr_StockOptionsAndRSUsIssuedAndOutstandingMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_JulyTwoThousandTwentyFourNotesAndDerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_JulyTwoThousandTwentyFourNotesAndDerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="cslr_JulyTwoThousandTwentyFourNotesAndDerivativeLiabilityMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityMember" xlink:href="cslr-20250629.xsd#cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="cslr_SeptemberTwoThousandTwentyFourNotesDerivativeLiabilityMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ThirdSAFEAgreementMember" xlink:href="cslr-20250629.xsd#cslr_ThirdSAFEAgreementMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="cslr_ThirdSAFEAgreementMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ForwardPurchaseAgreementsMember" xlink:href="cslr-20250629.xsd#cslr_ForwardPurchaseAgreementsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="cslr_ForwardPurchaseAgreementsMember" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:to="us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofFinancialPerformancethroughReportableSegmentsTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingRevenueReconcilingItemLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementBusinessSegmentsAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable" xlink:to="us-gaap_StatementBusinessSegmentsAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_SegmentDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_SegmentDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubsegmentsAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsegmentsAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTable" xlink:to="us-gaap_SubsegmentsAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubsegmentsDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsegmentsDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_SubsegmentsAxis" xlink:to="us-gaap_SubsegmentsDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubsegmentsDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsegmentsDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_SubsegmentsAxis" xlink:to="us-gaap_SubsegmentsDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentDomain" xlink:to="us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ResidentialSolarInstallationMember" xlink:href="cslr-20250629.xsd#cslr_ResidentialSolarInstallationMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsegmentsDomain" xlink:to="cslr_ResidentialSolarInstallationMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NewHomesBusinessMember" xlink:href="cslr-20250629.xsd#cslr_NewHomesBusinessMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsegmentsDomain" xlink:to="cslr_NewHomesBusinessMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Revenues" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_Revenues" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CostOfRevenue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_CostOfRevenue" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SalesCommissionsAndFees" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SalesCommissionsAndFees"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_SalesCommissionsAndFees" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SellingAndMarketingExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_SellingAndMarketingExpense" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_GeneralAndAdministrativeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_GeneralAndAdministrativeExpense" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OperatingIncomeLoss" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingIncomeLoss"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_OperatingIncomeLoss" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_InterestExpense" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InvestmentIncomeInterest" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentIncomeInterest"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_InvestmentIncomeInterest" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherNonoperatingIncomeExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_OtherNonoperatingIncomeExpense" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingRevenueReconcilingItemLineItems" xlink:to="us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" order="9" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/ScheduleofAssetsbySegmentTable" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentReportingAssetReconcilingItemLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingAssetReconcilingItemLineItems"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_SegmentReportingAssetReconcilingItemLineItems" xlink:to="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_ProductOrServiceAxis" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductOrServiceAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="us-gaap_ReconciliationOfAssetsFromSegmentToConsolidatedTable" xlink:to="srt_ProductOrServiceAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_ProductsAndServicesDomain" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_ProductOrServiceAxis" xlink:to="srt_ProductsAndServicesDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_ProductsAndServicesDomain_0" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ProductsAndServicesDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="srt_ProductOrServiceAxis" xlink:to="srt_ProductsAndServicesDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ResidentialSolarInstallationMember" xlink:href="cslr-20250629.xsd#cslr_ResidentialSolarInstallationMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_ProductsAndServicesDomain" xlink:to="cslr_ResidentialSolarInstallationMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NewHomesBusinessMember" xlink:href="cslr-20250629.xsd#cslr_NewHomesBusinessMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_ProductsAndServicesDomain" xlink:to="cslr_NewHomesBusinessMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Assets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Assets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingAssetReconcilingItemLineItems" xlink:to="us-gaap_Assets" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/OrganizationDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract"/>
    <loc xlink:type="locator" xlink:label="dei_EntityIncorporationDateOfIncorporation" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityIncorporationDateOfIncorporation"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="dei_EntityIncorporationDateOfIncorporation" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeLossFromContinuingOperations" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeLossFromContinuingOperations"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="us-gaap_IncomeLossFromContinuingOperations" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RetainedEarningsAccumulatedDeficit"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="us-gaap_RetainedEarningsAccumulatedDeficit" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShortTermBorrowings" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermBorrowings"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="us-gaap_ShortTermBorrowings" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RestrictedCashCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCashCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="us-gaap_RestrictedCashCurrent" order="4" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SummaryofSignificantAccountingPoliciesDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_SummaryofSignificantAccountingPoliciesDetailsTable" xlink:href="cslr-20250629.xsd#cslr_SummaryofSignificantAccountingPoliciesDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:to="cslr_SummaryofSignificantAccountingPoliciesDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RestatementAxis" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RestatementAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_SummaryofSignificantAccountingPoliciesDetailsTable" xlink:to="srt_RestatementAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RestatementDomain" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RestatementDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_RestatementAxis" xlink:to="srt_RestatementDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RestatementDomain_0" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RestatementDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="srt_RestatementAxis" xlink:to="srt_RestatementDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RangeAxis" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_SummaryofSignificantAccountingPoliciesDetailsTable" xlink:to="srt_RangeAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RangeMember" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RangeMember_0" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_MinimumMember" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RangeMember" xlink:to="srt_MinimumMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_MaximumMember" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RangeMember" xlink:to="srt_MaximumMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RestatementAdjustmentMember" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RestatementAdjustmentMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RestatementDomain" xlink:to="srt_RestatementAdjustmentMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_RevenueFromContractWithCustomer" xlink:href="cslr-20250629.xsd#cslr_RevenueFromContractWithCustomer"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:to="cslr_RevenueFromContractWithCustomer" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_InstallationProjectsTerm" xlink:href="cslr-20250629.xsd#cslr_InstallationProjectsTerm"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:to="cslr_InstallationProjectsTerm" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CostOfRevenue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:to="us-gaap_CostOfRevenue" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SellingAndMarketingExpense" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SellingAndMarketingExpense"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:to="us-gaap_SellingAndMarketingExpense" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BusinessCombinationDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationSegmentAllocationLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_BusinessCombinationDetailsTable" xlink:href="cslr-20250629.xsd#cslr_BusinessCombinationDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="cslr_BusinessCombinationDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BusinessCombinationDetailsTable" xlink:to="us-gaap_BusinessAcquisitionAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_BusinessAcquisitionAxis" xlink:to="us-gaap_BusinessAcquisitionAcquireeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessAcquisitionAcquireeDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_BusinessAcquisitionAxis" xlink:to="us-gaap_BusinessAcquisitionAcquireeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeStatementLocationAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BusinessCombinationDetailsTable" xlink:to="us-gaap_IncomeStatementLocationAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeStatementLocationDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_IncomeStatementLocationAxis" xlink:to="us-gaap_IncomeStatementLocationDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeStatementLocationDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeStatementLocationDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_IncomeStatementLocationAxis" xlink:to="us-gaap_IncomeStatementLocationDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_GeneralAndAdministrativeExpenseMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GeneralAndAdministrativeExpenseMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeStatementLocationDomain" xlink:to="us-gaap_GeneralAndAdministrativeExpenseMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SunPowerAcquisitionMember" xlink:href="cslr-20250629.xsd#cslr_SunPowerAcquisitionMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessAcquisitionAcquireeDomain" xlink:to="cslr_SunPowerAcquisitionMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PaymentsToAcquireBusinessesGross" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PaymentsToAcquireBusinessesGross"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_PaymentsToAcquireBusinessesGross" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CashAcquired" xlink:href="cslr-20250629.xsd#cslr_CashAcquired"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="cslr_CashAcquired" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_BusinessCombinationConsiderationTransferred1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_BusinessCombinationSegmentAllocationLineItems" xlink:to="us-gaap_BusinessCombinationConsiderationTransferred1" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/FairValueMeasurementsDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativesFairValueLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativesFairValueLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_FairValueMeasurementsDetailsTable" xlink:href="cslr-20250629.xsd#cslr_FairValueMeasurementsDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_DerivativesFairValueLineItems" xlink:to="cslr_FairValueMeasurementsDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_FairValueMeasurementsDetailsTable" xlink:to="us-gaap_DebtInstrumentAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SAFEAgreementsMember" xlink:href="cslr-20250629.xsd#cslr_SAFEAgreementsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_SAFEAgreementsMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativesFairValueLineItems" xlink:to="us-gaap_OtherLiabilities" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtConversionConvertedInstrumentRate" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionConvertedInstrumentRate"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativesFairValueLineItems" xlink:to="us-gaap_DebtConversionConvertedInstrumentRate" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtConversionOriginalDebtInterestRateOfDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtConversionOriginalDebtInterestRateOfDebt"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DerivativesFairValueLineItems" xlink:to="us-gaap_DebtConversionOriginalDebtInterestRateOfDebt" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/OtherIntangibleAssetsDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AmortizationOfIntangibleAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_GoodwillAndIntangibleAssetsDisclosureAbstract" xlink:to="us-gaap_AmortizationOfIntangibleAssets" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/AccruedExpensesandOtherCurrentLiabilitiesDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:to="us-gaap_OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:to="us-gaap_FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestPayableCurrentAndNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestPayableCurrentAndNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:to="us-gaap_InterestPayableCurrentAndNoncurrent" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProceedsFromRelatedPartyDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromRelatedPartyDebt"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrentAbstract" xlink:to="us-gaap_ProceedsFromRelatedPartyDebt" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/OtherExpenseIncomeNetDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DisaggregationOfIncomeStatementExpenseCaptionLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DisaggregationOfIncomeStatementExpenseCaptionLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_OtherExpenseIncomeNetDetailsTable" xlink:href="cslr-20250629.xsd#cslr_OtherExpenseIncomeNetDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_DisaggregationOfIncomeStatementExpenseCaptionLineItems" xlink:to="cslr_OtherExpenseIncomeNetDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_OtherExpenseIncomeNetDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TypeOfArrangementAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TypeOfArrangementAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_OtherExpenseIncomeNetDetailsTable" xlink:to="us-gaap_TypeOfArrangementAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_TypeOfArrangementAxis" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_TypeOfArrangementAxis" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ForwardPurchaseAgreementsMember" xlink:href="cslr-20250629.xsd#cslr_ForwardPurchaseAgreementsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:to="cslr_ForwardPurchaseAgreementsMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_BorrowingsAndDerivativeLiabilitiesMember" xlink:href="cslr-20250629.xsd#cslr_BorrowingsAndDerivativeLiabilitiesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="cslr_BorrowingsAndDerivativeLiabilitiesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_GainLossOnSaleOfDerivatives" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainLossOnSaleOfDerivatives"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DisaggregationOfIncomeStatementExpenseCaptionLineItems" xlink:to="us-gaap_GainLossOnSaleOfDerivatives" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherIncome"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DisaggregationOfIncomeStatementExpenseCaptionLineItems" xlink:to="us-gaap_OtherIncome" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/CapitalStockDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfStockLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_CapitalStockDetailsTable" xlink:href="cslr-20250629.xsd#cslr_CapitalStockDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="cslr_CapitalStockDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementEquityComponentsAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_CapitalStockDetailsTable" xlink:to="us-gaap_StatementEquityComponentsAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_CapitalStockDetailsTable" xlink:to="us-gaap_MeasurementInputTypeAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_MeasurementInputTypeAxis" xlink:to="us-gaap_MeasurementInputTypeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputTypeDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_MeasurementInputTypeAxis" xlink:to="us-gaap_MeasurementInputTypeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancingReceivablesPeriodPastDueAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_CapitalStockDetailsTable" xlink:to="us-gaap_FinancingReceivablesPeriodPastDueAxis" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:to="us-gaap_FinancingReceivablesPeriodPastDueDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinancingReceivablesPeriodPastDueDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancingReceivablesPeriodPastDueDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FinancingReceivablesPeriodPastDueAxis" xlink:to="us-gaap_FinancingReceivablesPeriodPastDueDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_CapitalStockDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionAxis" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionAxis" xlink:to="us-gaap_RelatedPartyTransactionDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionAxis" xlink:to="us-gaap_RelatedPartyTransactionDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_CapitalStockDetailsTable" xlink:to="us-gaap_ClassOfWarrantOrRightAxis" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_WhiteLionCapitalLLCMember" xlink:href="cslr-20250629.xsd#cslr_WhiteLionCapitalLLCMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyTransactionDomain" xlink:to="cslr_WhiteLionCapitalLLCMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_HourRapidMember" xlink:href="cslr-20250629.xsd#cslr_HourRapidMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyTransactionDomain" xlink:to="cslr_HourRapidMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_CommonStockMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PreferredStockMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_PreferredStockMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputOptionVolatilityMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputOptionVolatilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputOptionVolatilityMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_MeasurementInputRiskFreeInterestRateMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MeasurementInputRiskFreeInterestRateMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_MeasurementInputTypeDomain" xlink:to="us-gaap_MeasurementInputRiskFreeInterestRateMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TenDaysMember" xlink:href="cslr-20250629.xsd#cslr_TenDaysMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:to="cslr_TenDaysMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ThirtyDaysMember" xlink:href="cslr-20250629.xsd#cslr_ThirtyDaysMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:to="cslr_ThirtyDaysMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NinetyDaysMember" xlink:href="cslr-20250629.xsd#cslr_NinetyDaysMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_FinancingReceivablesPeriodPastDueDomain" xlink:to="cslr_NinetyDaysMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AynaWarrantMember" xlink:href="cslr-20250629.xsd#cslr_AynaWarrantMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_AynaWarrantMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CantorWarrantMember" xlink:href="cslr-20250629.xsd#cslr_CantorWarrantMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_CantorWarrantMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CarlyleWarrantsMember" xlink:href="cslr-20250629.xsd#cslr_CarlyleWarrantsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="cslr_CarlyleWarrantsMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WarrantMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="us-gaap_WarrantMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockSharesAuthorized" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_CommonStockSharesAuthorized" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PreferredStockSharesAuthorized" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_PreferredStockSharesAuthorized" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PreferredStockSharesIssued" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesIssued"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_PreferredStockSharesIssued" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PreferredStockSharesOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredStockSharesOutstanding"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_PreferredStockSharesOutstanding" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodValueNewIssues" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CommonStockOutstandingPercentage" xlink:href="cslr-20250629.xsd#cslr_CommonStockOutstandingPercentage"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="cslr_CommonStockOutstandingPercentage" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockSharesIssued" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_CommonStockSharesIssued" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockOptionExercisePriceDecrease" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockOptionExercisePriceDecrease"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_StockOptionExercisePriceDecrease" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAdjustmentOfWarrants" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAdjustmentOfWarrants"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_FairValueAdjustmentOfWarrants" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherExpenses" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherExpenses"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_OtherExpenses" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Cash" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Cash"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_Cash" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentUnamortizedDiscount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_DebtInstrumentUnamortizedDiscount" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ConvertibleNotesPayable" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ConvertibleNotesPayable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ConvertibleNotesPayable" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WarrantsAndRightsOutstandingMeasurementInput" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantsAndRightsOutstandingMeasurementInput"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_WarrantsAndRightsOutstandingMeasurementInput" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WarrantsAndRightsOutstandingTerm" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantsAndRightsOutstandingTerm"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_WarrantsAndRightsOutstandingTerm" order="16" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SharesIssuedPricePerShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssuedPricePerShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_SharesIssuedPricePerShare" order="17" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeNumberOfExercisableOptions" order="18" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightOutstanding"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightOutstanding" order="19" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PercentageOfCommonStockSharesIssued" xlink:href="cslr-20250629.xsd#cslr_PercentageOfCommonStockSharesIssued"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="cslr_PercentageOfCommonStockSharesIssued" order="20" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherIncome" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherIncome"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_OtherIncome" order="21" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharesOther" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesOther"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodSharesOther" order="22" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_GainsLossesOnExtinguishmentOfDebt" order="23" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AdjustmentsToAdditionalPaidInCapitalOther" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalOther"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockLineItems" xlink:to="us-gaap_AdjustmentsToAdditionalPaidInCapitalOther" order="24" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BorrowingsandDerivativeLiabilitiesDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_BorrowingsandDerivativeLiabilitiesDetailsTable" xlink:href="cslr-20250629.xsd#cslr_BorrowingsandDerivativeLiabilitiesDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="cslr_BorrowingsandDerivativeLiabilitiesDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RangeAxis" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesDetailsTable" xlink:to="srt_RangeAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RangeMember" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_RangeMember_0" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_RangeMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="srt_RangeAxis" xlink:to="srt_RangeMember_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinancialInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancialInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesDetailsTable" xlink:to="us-gaap_FinancialInstrumentAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_FinancialInstrumentAxis" xlink:to="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_FinancialInstrumentAxis" xlink:to="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CreditFacilityAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesDetailsTable" xlink:to="us-gaap_CreditFacilityAxis" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CreditFacilityDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_CreditFacilityAxis" xlink:to="us-gaap_CreditFacilityDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CreditFacilityDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CreditFacilityDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_CreditFacilityAxis" xlink:to="us-gaap_CreditFacilityDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementEquityComponentsAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesDetailsTable" xlink:to="us-gaap_StatementEquityComponentsAxis" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EquityComponentDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EquityComponentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_EquityComponentDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BorrowingsandDerivativeLiabilitiesDetailsTable" xlink:to="us-gaap_DebtInstrumentAxis" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RevolvingCreditFacilityMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CreditFacilityDomain" xlink:to="us-gaap_RevolvingCreditFacilityMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TermLoanMember" xlink:href="cslr-20250629.xsd#cslr_TermLoanMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CreditFacilityDomain" xlink:to="cslr_TermLoanMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_RevocableLivingTrustMember" xlink:href="cslr-20250629.xsd#cslr_RevocableLivingTrustMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CreditFacilityDomain" xlink:to="cslr_RevocableLivingTrustMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_RevolvingLoanMember" xlink:href="cslr-20250629.xsd#cslr_RevolvingLoanMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CreditFacilityDomain" xlink:to="cslr_RevolvingLoanMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SecuredCreditFacilityMember" xlink:href="cslr-20250629.xsd#cslr_SecuredCreditFacilityMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CreditFacilityDomain" xlink:to="cslr_SecuredCreditFacilityMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_MaximumMember" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MaximumMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RangeMember" xlink:to="srt_MaximumMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_MinimumMember" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_MinimumMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_RangeMember" xlink:to="srt_MinimumMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EquityComponentDomain" xlink:to="us-gaap_CommonStockMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CarlyleMember" xlink:href="cslr-20250629.xsd#cslr_CarlyleMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="cslr_CarlyleMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="us-gaap_RelatedPartyMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_KlineHillMember" xlink:href="cslr-20250629.xsd#cslr_KlineHillMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="cslr_KlineHillMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TwoThousandEighteenBridgeNotesMember" xlink:href="cslr-20250629.xsd#cslr_TwoThousandEighteenBridgeNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="cslr_TwoThousandEighteenBridgeNotesMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember" xlink:href="cslr-20250629.xsd#cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_TwelvePercentageSeniorUnsecuredConvertibleNotesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_July2024NotesMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember" xlink:href="cslr-20250629.xsd#cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_SevenPercentageSeniorUnsecuredConvertibleNotesMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_MasseyCharitableTrustMember" xlink:href="cslr-20250629.xsd#cslr_MasseyCharitableTrustMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_MasseyCharitableTrustMember" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_September2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_September2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_September2024NotesMember" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ConvertibleNotesTwoThousandsAndTwentyFourMember" xlink:href="cslr-20250629.xsd#cslr_ConvertibleNotesTwoThousandsAndTwentyFourMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_ConvertibleNotesTwoThousandsAndTwentyFourMember" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_JulyTwoThousandTwentyFourNotesMember" xlink:href="cslr-20250629.xsd#cslr_JulyTwoThousandTwentyFourNotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_JulyTwoThousandTwentyFourNotesMember" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_DebtInCSSolisMember" xlink:href="cslr-20250629.xsd#cslr_DebtInCSSolisMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_DebtInCSSolisMember" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SCILoanAgreementMember" xlink:href="cslr-20250629.xsd#cslr_SCILoanAgreementMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_SCILoanAgreementMember" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="us-gaap_DerivativeMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SeniorNotes" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SeniorNotes"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_SeniorNotes" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentIssuedPrincipal" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentIssuedPrincipal"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentIssuedPrincipal" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentInterestRateEffectivePercentage" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentMaturityDate" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentMaturityDate"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentMaturityDate" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentInterestRateStatedPercentage" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentConvertibleConversionPrice1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentConvertibleConversionPrice1" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeLiabilities" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeLiabilities"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DerivativeLiabilities" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FairValueAdjustmentOfWarrants" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FairValueAdjustmentOfWarrants"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_FairValueAdjustmentOfWarrants" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AmortizationOfDebtDiscountPremium" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmortizationOfDebtDiscountPremium"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_AmortizationOfDebtDiscountPremium" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_GainsLossesOnRestructuringOfDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_GainsLossesOnRestructuringOfDebt"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_GainsLossesOnRestructuringOfDebt" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentConvertibleIfConvertedValueInExcessOfPrincipal" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DerivativeGainLossOnDerivativeNet" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DerivativeGainLossOnDerivativeNet"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DerivativeGainLossOnDerivativeNet" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentFaceAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentFaceAmount" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockSharesIssued" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesIssued"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_CommonStockSharesIssued" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_CommonStockParOrStatedValuePerShare" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AmountOfImpairmentToCarryingAmountOfRegulatoryAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AmountOfImpairmentToCarryingAmountOfRegulatoryAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_AmountOfImpairmentToCarryingAmountOfRegulatoryAssets" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_FinancingReceivableRevolvingConvertedToTermLoan" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_FinancingReceivableRevolvingConvertedToTermLoan"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_FinancingReceivableRevolvingConvertedToTermLoan" order="16" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProceedsFromBankDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromBankDebt"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_ProceedsFromBankDebt" order="17" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProceedsFromSecuredLinesOfCredit" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromSecuredLinesOfCredit"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_ProceedsFromSecuredLinesOfCredit" order="18" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AdditionalGainAmount" xlink:href="cslr-20250629.xsd#cslr_AdditionalGainAmount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="cslr_AdditionalGainAmount" order="19" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AggregateGain" xlink:href="cslr-20250629.xsd#cslr_AggregateGain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="cslr_AggregateGain" order="20" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PreferredUnitsContributedCapital" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PreferredUnitsContributedCapital"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_PreferredUnitsContributedCapital" order="21" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentRedemptionPricePercentage" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentRedemptionPricePercentage"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_DebtInstrumentRedemptionPricePercentage" order="22" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_InvestmentDividendPayablePercentage" xlink:href="cslr-20250629.xsd#cslr_InvestmentDividendPayablePercentage"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="cslr_InvestmentDividendPayablePercentage" order="23" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" order="24" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SharesIssuedPricePerShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharesIssuedPricePerShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_SharesIssuedPricePerShare" order="25" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StockIssuedDuringPeriodSharesPurchaseOfAssets" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StockIssuedDuringPeriodSharesPurchaseOfAssets"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_StockIssuedDuringPeriodSharesPurchaseOfAssets" order="26" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SecuredCreditAgreement" xlink:href="cslr-20250629.xsd#cslr_SecuredCreditAgreement"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="cslr_SecuredCreditAgreement" order="27" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestPayableCurrentAndNoncurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestPayableCurrentAndNoncurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_InterestPayableCurrentAndNoncurrent" order="28" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestExpenseBorrowings" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseBorrowings"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_InterestExpenseBorrowings" order="29" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LineOfCredit" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCredit"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_LineOfCredit" order="30" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AnnualInterestRate" xlink:href="cslr-20250629.xsd#cslr_AnnualInterestRate"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="cslr_AnnualInterestRate" order="31" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LineOfCreditFacilityCollateralFeesAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityCollateralFeesAmount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_LineOfCreditFacilityCollateralFeesAmount" order="32" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_LineOfCreditFacilityFairValueOfAmountOutstanding" order="33" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentLineItems" xlink:to="us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" order="34" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SAFEAgreementsDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_SAFEAgreementsDetailsTable" xlink:href="cslr-20250629.xsd#cslr_SAFEAgreementsDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:to="cslr_SAFEAgreementsDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_TypeOfArrangementAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_TypeOfArrangementAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_SAFEAgreementsDetailsTable" xlink:to="us-gaap_TypeOfArrangementAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_TypeOfArrangementAxis" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ArrangementsAndNonarrangementTransactionsMember_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ArrangementsAndNonarrangementTransactionsMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_TypeOfArrangementAxis" xlink:to="us-gaap_ArrangementsAndNonarrangementTransactionsMember_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_FirstSAFEMember" xlink:href="cslr-20250629.xsd#cslr_FirstSAFEMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:to="cslr_FirstSAFEMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SecondSAFEMember" xlink:href="cslr-20250629.xsd#cslr_SecondSAFEMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:to="cslr_SecondSAFEMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ThirdSAFEMember" xlink:href="cslr-20250629.xsd#cslr_ThirdSAFEMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ArrangementsAndNonarrangementTransactionsMember" xlink:to="cslr_ThirdSAFEMember" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SimpleAgreementForFutureEquityTermsAndConditionsDescription" xlink:href="cslr-20250629.xsd#cslr_SimpleAgreementForFutureEquityTermsAndConditionsDescription"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:to="cslr_SimpleAgreementForFutureEquityTermsAndConditionsDescription" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SimpleAgreementForFutureEquityAmendmentDescription" xlink:href="cslr-20250629.xsd#cslr_SimpleAgreementForFutureEquityAmendmentDescription"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:to="cslr_SimpleAgreementForFutureEquityAmendmentDescription" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_EstimatedFairValueAmount" xlink:href="cslr-20250629.xsd#cslr_EstimatedFairValueAmount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:to="cslr_EstimatedFairValueAmount" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InterestExpenseOther" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InterestExpenseOther"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_CollaborativeArrangementsAndNoncollaborativeArrangementTransactionsLineItems" xlink:to="us-gaap_InterestExpenseOther" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/StockBasedCompensationDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_StockBasedCompensationDetailsTable" xlink:href="cslr-20250629.xsd#cslr_StockBasedCompensationDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="cslr_StockBasedCompensationDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PlanNameAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_StockBasedCompensationDetailsTable" xlink:to="us-gaap_PlanNameAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_PlanNameAxis" xlink:to="us-gaap_PlanNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_PlanNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_PlanNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_PlanNameAxis" xlink:to="us-gaap_PlanNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AwardTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AwardTypeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_StockBasedCompensationDetailsTable" xlink:to="us-gaap_AwardTypeAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_AwardTypeAxis" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_AwardTypeAxis" xlink:to="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ServiceBasedOptionMember" xlink:href="cslr-20250629.xsd#cslr_ServiceBasedOptionMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="cslr_ServiceBasedOptionMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RestrictedStockUnitsRSUMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="us-gaap_RestrictedStockUnitsRSUMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_TwoThousandTwentyThreeEquityIncentivePlanMember" xlink:href="cslr-20250629.xsd#cslr_TwoThousandTwentyThreeEquityIncentivePlanMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_PlanNameDomain" xlink:to="cslr_TwoThousandTwentyThreeEquityIncentivePlanMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ISOsUnderThe2023PlanMember" xlink:href="cslr-20250629.xsd#cslr_ISOsUnderThe2023PlanMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_PlanNameDomain" xlink:to="cslr_ISOsUnderThe2023PlanMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardPercentageOfOutstandingStockMaximum" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedStockOptions" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsLineItems" xlink:to="us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm1" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/CommitmentsandContingenciesDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_OtherCommitmentsLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherCommitmentsLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_CommitmentsandContingenciesDetailsTable" xlink:href="cslr-20250629.xsd#cslr_CommitmentsandContingenciesDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="cslr_CommitmentsandContingenciesDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_CommitmentsandContingenciesDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionAxis" xlink:to="us-gaap_RelatedPartyTransactionDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionAxis" xlink:to="us-gaap_RelatedPartyTransactionDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_LitigationCaseAxis" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_CommitmentsandContingenciesDetailsTable" xlink:to="srt_LitigationCaseAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_LitigationCaseTypeDomain" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="srt_LitigationCaseAxis" xlink:to="srt_LitigationCaseTypeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_LitigationCaseTypeDomain_0" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_LitigationCaseTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="srt_LitigationCaseAxis" xlink:to="srt_LitigationCaseTypeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SolarParkKoreaCoLTDMember" xlink:href="cslr-20250629.xsd#cslr_SolarParkKoreaCoLTDMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyTransactionDomain" xlink:to="cslr_SolarParkKoreaCoLTDMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AttorneyMember" xlink:href="cslr-20250629.xsd#cslr_AttorneyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyTransactionDomain" xlink:to="cslr_AttorneyMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SiemensLitigationMember" xlink:href="cslr-20250629.xsd#cslr_SiemensLitigationMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_LitigationCaseTypeDomain" xlink:to="cslr_SiemensLitigationMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LossContingencyAccrualCarryingValueCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingencyAccrualCarryingValueCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="us-gaap_LossContingencyAccrualCarryingValueCurrent" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LossContingencyDamagesSoughtValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingencyDamagesSoughtValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="us-gaap_LossContingencyDamagesSoughtValue" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LossContingencyDamagesAwardedValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LossContingencyDamagesAwardedValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="us-gaap_LossContingencyDamagesAwardedValue" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SubsidiariesIndemnityObligations" xlink:href="cslr-20250629.xsd#cslr_SubsidiariesIndemnityObligations"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="cslr_SubsidiariesIndemnityObligations" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LegalFees" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LegalFees"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="us-gaap_LegalFees" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_AccrualAmountOfLegalLosses" xlink:href="cslr-20250629.xsd#cslr_AccrualAmountOfLegalLosses"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="cslr_AccrualAmountOfLegalLosses" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_OtherExpenses" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherExpenses"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="us-gaap_OtherExpenses" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_LettersOfCreditOutstandingAmount" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LettersOfCreditOutstandingAmount"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="us-gaap_LettersOfCreditOutstandingAmount" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RestrictedCash" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RestrictedCash"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_OtherCommitmentsLineItems" xlink:to="us-gaap_RestrictedCash" order="9" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/IncomeTaxesDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeTaxDisclosureAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxDisclosureAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_IncomeTaxExpenseBenefit" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_IncomeTaxExpenseBenefit"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_IncomeTaxDisclosureAbstract" xlink:to="us-gaap_IncomeTaxExpenseBenefit" order="0" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/BasicandDilutedNetLossPerShareDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_EarningsPerShareBasicLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EarningsPerShareBasicLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_BasicandDilutedNetLossPerShareDetailsTable" xlink:href="cslr-20250629.xsd#cslr_BasicandDilutedNetLossPerShareDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_EarningsPerShareBasicLineItems" xlink:to="cslr_BasicandDilutedNetLossPerShareDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_BasicandDilutedNetLossPerShareDetailsTable" xlink:to="us-gaap_ClassOfWarrantOrRightAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfWarrantOrRightDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfWarrantOrRightDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_ClassOfWarrantOrRightAxis" xlink:to="us-gaap_ClassOfWarrantOrRightDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WarrantMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WarrantMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfWarrantOrRightDomain" xlink:to="us-gaap_WarrantMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Dividends" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Dividends"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EarningsPerShareBasicLineItems" xlink:to="us-gaap_Dividends" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_WeightedAverageBasicSharesOutstandingProForma" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_WeightedAverageBasicSharesOutstandingProForma"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_EarningsPerShareBasicLineItems" xlink:to="us-gaap_WeightedAverageBasicSharesOutstandingProForma" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SegmentInformationDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentReportingInformationLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_SegmentInformationDetailsTable" xlink:href="cslr-20250629.xsd#cslr_SegmentInformationDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="cslr_SegmentInformationDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementBusinessSegmentsAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_SegmentInformationDetailsTable" xlink:to="us-gaap_StatementBusinessSegmentsAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_SegmentDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_SegmentDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_SegmentInformationDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentDomain" xlink:to="us-gaap_ReportableSegmentAggregationBeforeOtherOperatingSegmentMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ResidentialSolarInstallationMember" xlink:href="cslr-20250629.xsd#cslr_ResidentialSolarInstallationMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="cslr_ResidentialSolarInstallationMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NewHomesBusinessMember" xlink:href="cslr-20250629.xsd#cslr_NewHomesBusinessMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="cslr_NewHomesBusinessMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_NumberOfReportableSegments" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_NumberOfReportableSegments"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_NumberOfReportableSegments" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DepreciationDepletionAndAmortization" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_DepreciationDepletionAndAmortization" order="3" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/RelatedPartyTransactionsDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_RelatedPartyTransactionsDetailsTable" xlink:href="cslr-20250629.xsd#cslr_RelatedPartyTransactionsDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_RelatedPartyTransactionLineItems" xlink:to="cslr_RelatedPartyTransactionsDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_RelatedPartyTransactionsDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionAxis" xlink:to="us-gaap_RelatedPartyTransactionDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionAxis" xlink:to="us-gaap_RelatedPartyTransactionDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_RelatedPartyTransactionsDetailsTable" xlink:to="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="us-gaap_RelatedPartyDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_RelatedPartyMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RelatedPartyMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyTransactionDomain" xlink:to="us-gaap_RelatedPartyMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_SameDaySolarMember" xlink:href="cslr-20250629.xsd#cslr_SameDaySolarMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyDomain" xlink:to="cslr_SameDaySolarMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_Revenues" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_Revenues"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyTransactionLineItems" xlink:to="us-gaap_Revenues" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CostOfRevenue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CostOfRevenue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_RelatedPartyTransactionLineItems" xlink:to="us-gaap_CostOfRevenue" order="1" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/SubsequentEventsDetails" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_SubsequentEventLineItems" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventLineItems"/>
    <loc xlink:type="locator" xlink:label="cslr_SubsequentEventsDetailsTable" xlink:href="cslr-20250629.xsd#cslr_SubsequentEventsDetailsTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="cslr_SubsequentEventsDetailsTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubsequentEventTypeAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_SubsequentEventsDetailsTable" xlink:to="us-gaap_SubsequentEventTypeAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubsequentEventTypeDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_SubsequentEventTypeAxis" xlink:to="us-gaap_SubsequentEventTypeDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubsequentEventTypeDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_SubsequentEventTypeAxis" xlink:to="us-gaap_SubsequentEventTypeDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="cslr_SubsequentEventsDetailsTable" xlink:to="us-gaap_DebtInstrumentAxis" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentNameDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_DebtInstrumentAxis" xlink:to="us-gaap_DebtInstrumentNameDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_SubsequentEventMember" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_SubsequentEventMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventTypeDomain" xlink:to="us-gaap_SubsequentEventMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_July2024NotesMember" xlink:href="cslr-20250629.xsd#cslr_July2024NotesMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_DebtInstrumentNameDomain" xlink:to="cslr_July2024NotesMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_PercentageOfIssuanceConvertibleSeniorUnsecuredConvertibleNotes" xlink:href="cslr-20250629.xsd#cslr_PercentageOfIssuanceConvertibleSeniorUnsecuredConvertibleNotes"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="cslr_PercentageOfIssuanceConvertibleSeniorUnsecuredConvertibleNotes" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ProceedsFromRelatedPartyDebt" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ProceedsFromRelatedPartyDebt"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="us-gaap_ProceedsFromRelatedPartyDebt" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_DebtInstrumentFairValue" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_DebtInstrumentFairValue"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="us-gaap_DebtInstrumentFairValue" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_InvestmentInterestRate" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentInterestRate"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="us-gaap_InvestmentInterestRate" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockSharesAuthorized" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockSharesAuthorized"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="us-gaap_CommonStockSharesAuthorized" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_CommonStockParOrStatedValuePerShare" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_CommonStockParOrStatedValuePerShare"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="us-gaap_CommonStockParOrStatedValuePerShare" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NumberOfTradingDays" xlink:href="cslr-20250629.xsd#cslr_NumberOfTradingDays"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="cslr_NumberOfTradingDays" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_ConsecutiveTradingDays" xlink:href="cslr-20250629.xsd#cslr_ConsecutiveTradingDays"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="cslr_ConsecutiveTradingDays" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_NoticePeriod" xlink:href="cslr-20250629.xsd#cslr_NoticePeriod"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_SubsequentEventLineItems" xlink:to="cslr_NoticePeriod" order="8" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="us-gaap_LiabilitiesCurrentAbstract" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_LiabilitiesCurrentAbstract"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_LiabilitiesCurrentAbstract" xlink:to="us-gaap_AccountsPayableCurrent" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_LiabilitiesCurrentAbstract" xlink:to="us-gaap_AccountsPayableAndOtherAccruedLiabilitiesCurrent" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <loc xlink:type="locator" xlink:label="srt_ChiefExecutiveOfficerMember" xlink:href="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd#srt_ChiefExecutiveOfficerMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:to="srt_ChiefExecutiveOfficerMember" order="2" xbrldt:closed="true"/>
  </definitionLink>
  <definitionLink xlink:role="http://www.FreedomAcquisitionICorp.com/role/DocumentAndEntityInformation" xlink:type="extended">
    <loc xlink:type="locator" xlink:label="dei_DocumentInformationLineItems" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentInformationLineItems"/>
    <loc xlink:type="locator" xlink:label="dei_DocumentInformationTable" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentInformationTable"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_DocumentInformationTable" order="0" xbrldt:contextElement="segment" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_StatementClassOfStockAxis" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_StatementClassOfStockAxis"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="dei_DocumentInformationTable" xlink:to="us-gaap_StatementClassOfStockAxis" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfStockDomain" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="us-gaap_StatementClassOfStockAxis" xlink:to="us-gaap_ClassOfStockDomain" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="us-gaap_ClassOfStockDomain_0" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ClassOfStockDomain"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="us-gaap_StatementClassOfStockAxis" xlink:to="us-gaap_ClassOfStockDomain_0" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_CommonStockParValue00001PerShareMember" xlink:href="cslr-20250629.xsd#cslr_CommonStockParValue00001PerShareMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockDomain" xlink:to="cslr_CommonStockParValue00001PerShareMember" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="cslr_RedeemableWarrantsEachWholeWarrantExercisableForOneShareOfCommonStockMember" xlink:href="cslr-20250629.xsd#cslr_RedeemableWarrantsEachWholeWarrantExercisableForOneShareOfCommonStockMember"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="us-gaap_ClassOfStockDomain" xlink:to="cslr_RedeemableWarrantsEachWholeWarrantExercisableForOneShareOfCommonStockMember" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_DocumentType" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentType"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_DocumentType" order="0" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_DocumentQuarterlyReport" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentQuarterlyReport"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_DocumentQuarterlyReport" order="1" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_DocumentPeriodEndDate" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentPeriodEndDate"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_DocumentPeriodEndDate" order="2" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_DocumentFiscalYearFocus" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentFiscalYearFocus"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_DocumentFiscalYearFocus" order="3" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_DocumentTransitionReport" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_DocumentTransitionReport"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_DocumentTransitionReport" order="4" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityFileNumber" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFileNumber"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityFileNumber" order="5" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityRegistrantName" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityRegistrantName"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityRegistrantName" order="6" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityIncorporationStateCountryCode" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityIncorporationStateCountryCode"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityIncorporationStateCountryCode" order="7" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityTaxIdentificationNumber" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityTaxIdentificationNumber"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityTaxIdentificationNumber" order="8" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityAddressAddressLine1" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressAddressLine1"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityAddressAddressLine1" order="9" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityAddressCityOrTown" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCityOrTown"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityAddressCityOrTown" order="10" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityAddressCountry" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressCountry"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityAddressCountry" order="11" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityAddressPostalZipCode" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityAddressPostalZipCode"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityAddressPostalZipCode" order="12" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_CityAreaCode" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_CityAreaCode"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_CityAreaCode" order="13" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_LocalPhoneNumber" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_LocalPhoneNumber"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_LocalPhoneNumber" order="14" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_Security12bTitle" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_Security12bTitle"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_Security12bTitle" order="15" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_TradingSymbol" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_TradingSymbol"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_TradingSymbol" order="16" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_SecurityExchangeName" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_SecurityExchangeName"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_SecurityExchangeName" order="17" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityCurrentReportingStatus" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCurrentReportingStatus"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityCurrentReportingStatus" order="18" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityInteractiveDataCurrent" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityInteractiveDataCurrent"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityInteractiveDataCurrent" order="19" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityFilerCategory" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityFilerCategory"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityFilerCategory" order="20" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntitySmallBusiness" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntitySmallBusiness"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntitySmallBusiness" order="21" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityEmergingGrowthCompany" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityEmergingGrowthCompany"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityEmergingGrowthCompany" order="22" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityExTransitionPeriod" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityExTransitionPeriod"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityExTransitionPeriod" order="23" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityShellCompany" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityShellCompany"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityShellCompany" order="24" xbrldt:closed="true"/>
    <loc xlink:type="locator" xlink:label="dei_EntityCommonStockSharesOutstanding" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_EntityCommonStockSharesOutstanding"/>
    <definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="dei_DocumentInformationLineItems" xlink:to="dei_EntityCommonStockSharesOutstanding" order="25" xbrldt:closed="true"/>
  </definitionLink>
</linkbase>
