<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019e21ef-63a6-729c-9484-e16249afc1ee,g:07cc1eea-7069-42db-910a-0f478eaf06d0-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.alkami.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSParenthetical" xlink:type="simple" xlink:href="alk-20260630.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSParenthetical"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFOPERATIONSParenthetical" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019e21ef-6498-74f8-9373-b9d234da25ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019e21ef-6498-7fdc-9127-e336e9d4ebac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019e21ef-6498-74f8-9373-b9d234da25ab" xlink:to="loc_us-gaap_StatementTable_019e21ef-6498-7fdc-9127-e336e9d4ebac" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019e21ef-6498-725c-927b-a114a908d906" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e21ef-6498-7fdc-9127-e336e9d4ebac" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019e21ef-6498-725c-927b-a114a908d906" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-6498-725c-927b-a114a908d906_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019e21ef-6498-725c-927b-a114a908d906" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-6498-725c-927b-a114a908d906_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-6498-74ac-a26c-10bf35e6e007" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019e21ef-6498-725c-927b-a114a908d906" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-6498-74ac-a26c-10bf35e6e007" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TechnologyBasedIntangibleAssetsMember_019e21ef-6498-732b-9536-c27a5a3cda82" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TechnologyBasedIntangibleAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-6498-74ac-a26c-10bf35e6e007" xlink:to="loc_us-gaap_TechnologyBasedIntangibleAssetsMember_019e21ef-6498-732b-9536-c27a5a3cda82" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_019e21ef-6498-7488-a7c7-2f7fa0531c00" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e21ef-6498-74f8-9373-b9d234da25ab" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_019e21ef-6498-7488-a7c7-2f7fa0531c00" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINSTOCKHOLDERSEQUITY" xlink:type="simple" xlink:href="alk-20260630.xsd#CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINSTOCKHOLDERSEQUITY"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/CONDENSEDCONSOLIDATEDSTATEMENTSOFCHANGESINSTOCKHOLDERSEQUITY" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_019e21ef-6498-79c5-a331-d6cd5f31503e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_019e21ef-6498-79e0-917e-108c1dbe7a55" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_019e21ef-6498-79c5-a331-d6cd5f31503e" xlink:to="loc_us-gaap_StatementTable_019e21ef-6498-79e0-917e-108c1dbe7a55" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019e21ef-6498-71a3-8d2a-b564deccdbe4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_019e21ef-6498-79e0-917e-108c1dbe7a55" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019e21ef-6498-71a3-8d2a-b564deccdbe4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e21ef-6498-71a3-8d2a-b564deccdbe4_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e21ef-6498-71a3-8d2a-b564deccdbe4" xlink:to="loc_us-gaap_EquityComponentDomain_019e21ef-6498-71a3-8d2a-b564deccdbe4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e21ef-6498-7b24-aa7c-b9eda00ddbc4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e21ef-6498-71a3-8d2a-b564deccdbe4" xlink:to="loc_us-gaap_EquityComponentDomain_019e21ef-6498-7b24-aa7c-b9eda00ddbc4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019e21ef-6498-72a2-a7ea-b096f0be3986" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e21ef-6498-7b24-aa7c-b9eda00ddbc4" xlink:to="loc_us-gaap_CommonStockMember_019e21ef-6498-72a2-a7ea-b096f0be3986" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_019e21ef-6498-7cd6-8ca6-819f2517c159" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e21ef-6498-7b24-aa7c-b9eda00ddbc4" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_019e21ef-6498-7cd6-8ca6-819f2517c159" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019e21ef-6498-7154-9a8c-ecfdf975a897" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e21ef-6498-7b24-aa7c-b9eda00ddbc4" xlink:to="loc_us-gaap_RetainedEarningsMember_019e21ef-6498-7154-9a8c-ecfdf975a897" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_019e21ef-6498-79c5-a331-d6cd5f31503e" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019e21ef-6498-796f-beb8-31591749031f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_CommonStockSharesOutstanding_019e21ef-6498-796f-beb8-31591749031f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e21ef-6498-7541-8ca3-a28e39ca2e72" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockholdersEquity_019e21ef-6498-7541-8ca3-a28e39ca2e72" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019e21ef-6498-7976-ac57-d3259b682cad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019e21ef-6498-7976-ac57-d3259b682cad" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_019e21ef-6498-732d-95e1-d0eed7e23f8f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_019e21ef-6498-732d-95e1-d0eed7e23f8f" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_019e21ef-6498-73fe-b760-4d6960eabba7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_019e21ef-6498-73fe-b760-4d6960eabba7" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_019e6ddf-1de1-7098-a2a0-621902ff799f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_019e6ddf-1de1-7098-a2a0-621902ff799f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_019e6ddf-1de1-7ca1-954f-ef8555f7f4a4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_019e6ddf-1de1-7ca1-954f-ef8555f7f4a4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019e21ef-6498-7724-8081-c64d4e660e1d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_019e21ef-6498-7724-8081-c64d4e660e1d" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_019e21ef-6498-71ef-9058-3cb151df75d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_019e21ef-6498-71ef-9058-3cb151df75d4" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_019f605a-01bd-73e5-be22-14b3190741e7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_AdjustmentsRelatedToTaxWithholdingForShareBasedCompensation_019f605a-01bd-73e5-be22-14b3190741e7" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_AdjustmentsToAdditionalPaidInCapitalCappedCallTransactions_019e21ef-6498-7b25-a42c-9b5f851e7972" xlink:href="alk-20260630.xsd#alk_AdjustmentsToAdditionalPaidInCapitalCappedCallTransactions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_alk_AdjustmentsToAdditionalPaidInCapitalCappedCallTransactions_019e21ef-6498-7b25-a42c-9b5f851e7972" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_019f604f-4b9f-7e18-8727-214ad5d6e02f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_019f604f-4b9f-7e18-8727-214ad5d6e02f" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_019f604f-ca8e-71a2-96ed-9390210e4ecc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_019f604f-ca8e-71a2-96ed-9390210e4ecc" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_ShareBasedCompensationReplacementAwardsRelatedToMergerConsiderationAndAttributableToPreCombinationServices_019f605a-01bd-78e4-bb1c-4a1f3d15a229" xlink:href="alk-20260630.xsd#alk_ShareBasedCompensationReplacementAwardsRelatedToMergerConsiderationAndAttributableToPreCombinationServices"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_alk_ShareBasedCompensationReplacementAwardsRelatedToMergerConsiderationAndAttributableToPreCombinationServices_019f605a-01bd-78e4-bb1c-4a1f3d15a229" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019e21ef-6498-7b4b-80fc-888afadfd1e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e21ef-6498-7776-86ba-230d437fab56" xlink:to="loc_us-gaap_NetIncomeLoss_019e21ef-6498-7b4b-80fc-888afadfd1e0" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockSharesOutstanding_019e21ef-6498-70ee-9704-98744d278bbb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e21ef-6498-7a4f-a68b-7e2d87f51522" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/PropertyandEquipmentNetScheduleofPropertyandEquipmentNetDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#PropertyandEquipmentNetScheduleofPropertyandEquipmentNetDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/PropertyandEquipmentNetScheduleofPropertyandEquipmentNetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019e21ef-6499-7778-96cf-0ab44feba796" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019e21ef-6499-74e2-9fa0-249bc6c52bfa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019e21ef-6499-7778-96cf-0ab44feba796" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019e21ef-6499-74e2-9fa0-249bc6c52bfa" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019e21ef-6499-729a-a93c-fd74e1579238" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019e21ef-6499-74e2-9fa0-249bc6c52bfa" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019e21ef-6499-729a-a93c-fd74e1579238" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019e21ef-6499-729a-a93c-fd74e1579238_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019e21ef-6499-729a-a93c-fd74e1579238" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019e21ef-6499-729a-a93c-fd74e1579238_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019e21ef-6499-72b4-8468-680d4d7b0436" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_019e21ef-6499-729a-a93c-fd74e1579238" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019e21ef-6499-72b4-8468-680d4d7b0436" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019e21ef-6499-70cf-bf7e-9bafdc9f82c4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SoftwareAndSoftwareDevelopmentCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019e21ef-6499-72b4-8468-680d4d7b0436" xlink:to="loc_us-gaap_SoftwareAndSoftwareDevelopmentCostsMember_019e21ef-6499-70cf-bf7e-9bafdc9f82c4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_EquipmentAndSoftwareMember_019e21ef-6499-76cd-b55b-663c0d0cb205" xlink:href="alk-20260630.xsd#alk_EquipmentAndSoftwareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019e21ef-6499-72b4-8468-680d4d7b0436" xlink:to="loc_alk_EquipmentAndSoftwareMember_019e21ef-6499-76cd-b55b-663c0d0cb205" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_019e21ef-6499-77b3-9282-7de98ae15616" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeaseholdImprovementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_019e21ef-6499-72b4-8468-680d4d7b0436" xlink:to="loc_us-gaap_LeaseholdImprovementsMember_019e21ef-6499-77b3-9282-7de98ae15616" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019e21ef-6499-73f5-9e08-1099fa363c9b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_019e21ef-6499-74e2-9fa0-249bc6c52bfa" xlink:to="loc_srt_RangeAxis_019e21ef-6499-73f5-9e08-1099fa363c9b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e21ef-6499-73f5-9e08-1099fa363c9b_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019e21ef-6499-73f5-9e08-1099fa363c9b" xlink:to="loc_srt_RangeMember_019e21ef-6499-73f5-9e08-1099fa363c9b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e21ef-6499-7696-bbe0-ecfb9c306236" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019e21ef-6499-73f5-9e08-1099fa363c9b" xlink:to="loc_srt_RangeMember_019e21ef-6499-7696-bbe0-ecfb9c306236" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019e21ef-6499-755f-a38c-cd100bff9c38" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e21ef-6499-7696-bbe0-ecfb9c306236" xlink:to="loc_srt_MinimumMember_019e21ef-6499-755f-a38c-cd100bff9c38" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019e21ef-6499-779f-a700-1df726d9dc46" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e21ef-6499-7696-bbe0-ecfb9c306236" xlink:to="loc_srt_MaximumMember_019e21ef-6499-779f-a700-1df726d9dc46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_019e21ef-6499-7a27-aaef-f10d333ff9cd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019e21ef-6499-7778-96cf-0ab44feba796" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_019e21ef-6499-7a27-aaef-f10d333ff9cd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_019e21ef-6499-7dc1-9609-5f0ad1db75a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019e21ef-6499-7778-96cf-0ab44feba796" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentGross_019e21ef-6499-7dc1-9609-5f0ad1db75a5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019e21ef-6499-7978-9b07-66fb6c29eb25" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019e21ef-6499-7778-96cf-0ab44feba796" xlink:to="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_019e21ef-6499-7978-9b07-66fb6c29eb25" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_019e21ef-6499-7ce5-ae7c-08acc77c56be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_019e21ef-6499-7778-96cf-0ab44feba796" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_019e21ef-6499-7ce5-ae7c-08acc77c56be" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/RevenuesandDeferredCostsScheduleofDisaggregationofRevenueDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#RevenuesandDeferredCostsScheduleofDisaggregationofRevenueDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/RevenuesandDeferredCostsScheduleofDisaggregationofRevenueDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-7f3f-a2ac-7b6d94ec9f20" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-786e-b691-02e5138a2729" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-7f3f-a2ac-7b6d94ec9f20" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-786e-b691-02e5138a2729" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019e21ef-6499-73f0-9f57-24495291a4ba" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-786e-b691-02e5138a2729" xlink:to="loc_srt_ProductOrServiceAxis_019e21ef-6499-73f0-9f57-24495291a4ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019e21ef-6499-73f0-9f57-24495291a4ba_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019e21ef-6499-73f0-9f57-24495291a4ba" xlink:to="loc_srt_ProductsAndServicesDomain_019e21ef-6499-73f0-9f57-24495291a4ba_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019e21ef-6499-7ca9-a75c-522a27fbd0d5" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019e21ef-6499-73f0-9f57-24495291a4ba" xlink:to="loc_srt_ProductsAndServicesDomain_019e21ef-6499-7ca9-a75c-522a27fbd0d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_SaaSSubscriptionServicesMember_019e21ef-6499-78b1-82e5-232e130ea6fd" xlink:href="alk-20260630.xsd#alk_SaaSSubscriptionServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e21ef-6499-7ca9-a75c-522a27fbd0d5" xlink:to="loc_alk_SaaSSubscriptionServicesMember_019e21ef-6499-78b1-82e5-232e130ea6fd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_ImplementationServicesMember_019e21ef-6499-7af3-ac04-e75f3542eaac" xlink:href="alk-20260630.xsd#alk_ImplementationServicesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e21ef-6499-7ca9-a75c-522a27fbd0d5" xlink:to="loc_alk_ImplementationServicesMember_019e21ef-6499-7af3-ac04-e75f3542eaac" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ServiceOtherMember_019e21ef-6499-7ba9-8014-a9b4dafb6e64" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ServiceOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e21ef-6499-7ca9-a75c-522a27fbd0d5" xlink:to="loc_us-gaap_ServiceOtherMember_019e21ef-6499-7ba9-8014-a9b4dafb6e64" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e21ef-6499-7e51-8530-9d82d2bab4c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-7f3f-a2ac-7b6d94ec9f20" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e21ef-6499-7e51-8530-9d82d2bab4c6" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/RevenuesandDeferredCostsNarrativeDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#RevenuesandDeferredCostsNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/RevenuesandDeferredCostsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-78b4-82c9-1d7d54b33ab5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-78b4-82c9-1d7d54b33ab5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_019e21ef-6499-7c06-bc0e-f22a52f9eba4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-78b4-82c9-1d7d54b33ab5" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis_019e21ef-6499-7c06-bc0e-f22a52f9eba4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAxis_019e21ef-6499-7974-b3c4-a932008326f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-78b4-82c9-1d7d54b33ab5" xlink:to="loc_us-gaap_CapitalizedContractCostAxis_019e21ef-6499-7974-b3c4-a932008326f6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7974-b3c4-a932008326f6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_019e21ef-6499-7974-b3c4-a932008326f6" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7974-b3c4-a932008326f6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7038-87e4-e2a389b55795" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_019e21ef-6499-7974-b3c4-a932008326f6" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7038-87e4-e2a389b55795" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DeferredCommissionsCostsMember_019e21ef-6499-78ef-bab2-1dd2703438d9" xlink:href="alk-20260630.xsd#alk_DeferredCommissionsCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7038-87e4-e2a389b55795" xlink:to="loc_alk_DeferredCommissionsCostsMember_019e21ef-6499-78ef-bab2-1dd2703438d9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DeferredImplementationCostsMember_019e21ef-6499-71de-9014-c9d507105216" xlink:href="alk-20260630.xsd#alk_DeferredImplementationCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7038-87e4-e2a389b55795" xlink:to="loc_alk_DeferredImplementationCostsMember_019e21ef-6499-71de-9014-c9d507105216" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_019e21ef-6499-74ca-b82d-6336142cc33f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiabilityRevenueRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_019e21ef-6499-74ca-b82d-6336142cc33f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_019e21ef-6499-77d8-bd36-29a616e0cc02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_019e21ef-6499-77d8-bd36-29a616e0cc02" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_019e21ef-6499-7106-bce1-719c488ec356" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_019e21ef-6499-7106-bce1-719c488ec356" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_019e21ef-6499-73d7-8b0a-dd8f80c7c5f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_019e21ef-6499-73d7-8b0a-dd8f80c7c5f3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNet_019e21ef-6499-7959-a4d4-b6201cbd09f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_ContractWithCustomerAssetNet_019e21ef-6499-7959-a4d4-b6201cbd09f1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_CapitalizedContractCostsIncurredDuringPeriod_019e21ef-6499-71de-8aa4-2355e3b299bd" xlink:href="alk-20260630.xsd#alk_CapitalizedContractCostsIncurredDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_alk_CapitalizedContractCostsIncurredDuringPeriod_019e21ef-6499-71de-8aa4-2355e3b299bd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAmortization_019e21ef-6499-788a-aae1-efa6f9d805ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_CapitalizedContractCostAmortization_019e21ef-6499-788a-aae1-efa6f9d805ad" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostNet_019e21ef-6499-7a6b-88f1-1263ce5b1aac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_CapitalizedContractCostNet_019e21ef-6499-7a6b-88f1-1263ce5b1aac" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostImpairmentLoss_019e21ef-6499-7129-bebe-928414b9d734" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_CapitalizedContractCostImpairmentLoss_019e21ef-6499-7129-bebe-928414b9d734" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/RevenuesandDeferredCostsNarrativeDetails_1" xlink:type="simple" xlink:href="alk-20260630.xsd#RevenuesandDeferredCostsNarrativeDetails_1"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/RevenuesandDeferredCostsNarrativeDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-78b4-82c9-1d7d54b33ab5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-78b4-82c9-1d7d54b33ab5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAxis_019e21ef-6499-7974-b3c4-a932008326f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_019e21ef-6499-78b4-82c9-1d7d54b33ab5" xlink:to="loc_us-gaap_CapitalizedContractCostAxis_019e21ef-6499-7974-b3c4-a932008326f6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7974-b3c4-a932008326f6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_019e21ef-6499-7974-b3c4-a932008326f6" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7974-b3c4-a932008326f6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7038-87e4-e2a389b55795" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CapitalizedContractCostAxis_019e21ef-6499-7974-b3c4-a932008326f6" xlink:to="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7038-87e4-e2a389b55795" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DeferredCommissionsCostsMember_019e21ef-6499-78ef-bab2-1dd2703438d9" xlink:href="alk-20260630.xsd#alk_DeferredCommissionsCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7038-87e4-e2a389b55795" xlink:to="loc_alk_DeferredCommissionsCostsMember_019e21ef-6499-78ef-bab2-1dd2703438d9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DeferredImplementationCostsMember_019e21ef-6499-71de-9014-c9d507105216" xlink:href="alk-20260630.xsd#alk_DeferredImplementationCostsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CapitalizedContractCostDomain_019e21ef-6499-7038-87e4-e2a389b55795" xlink:to="loc_alk_DeferredImplementationCostsMember_019e21ef-6499-71de-9014-c9d507105216" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_019e21ef-6499-74ca-b82d-6336142cc33f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiabilityRevenueRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_019e21ef-6499-74ca-b82d-6336142cc33f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation_019e21ef-6499-77d8-bd36-29a616e0cc02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligation_019e21ef-6499-77d8-bd36-29a616e0cc02" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_019e21ef-6499-7106-bce1-719c488ec356" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligationPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationPercentage_019e21ef-6499-7106-bce1-719c488ec356" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_019e21ef-6499-73d7-8b0a-dd8f80c7c5f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1_019e21ef-6499-73d7-8b0a-dd8f80c7c5f3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerAssetNet_019e21ef-6499-7959-a4d4-b6201cbd09f1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_ContractWithCustomerAssetNet_019e21ef-6499-7959-a4d4-b6201cbd09f1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_CapitalizedContractCostsIncurredDuringPeriod_019e21ef-6499-71de-8aa4-2355e3b299bd" xlink:href="alk-20260630.xsd#alk_CapitalizedContractCostsIncurredDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_alk_CapitalizedContractCostsIncurredDuringPeriod_019e21ef-6499-71de-8aa4-2355e3b299bd" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostAmortization_019e21ef-6499-788a-aae1-efa6f9d805ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_CapitalizedContractCostAmortization_019e21ef-6499-788a-aae1-efa6f9d805ad" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostNet_019e21ef-6499-7a6b-88f1-1263ce5b1aac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_CapitalizedContractCostNet_019e21ef-6499-7a6b-88f1-1263ce5b1aac" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalizedContractCostImpairmentLoss_019e21ef-6499-7129-bebe-928414b9d734" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalizedContractCostImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_019e21ef-6499-774f-9823-c6c583030599" xlink:to="loc_us-gaap_CapitalizedContractCostImpairmentLoss_019e21ef-6499-7129-bebe-928414b9d734" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/AccountsReceivablenetDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#AccountsReceivablenetDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/AccountsReceivablenetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e21ef-6499-701f-b879-feef5953555e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e21ef-6499-7d79-87b4-04cfcae7aa46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e21ef-6499-701f-b879-feef5953555e" xlink:to="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e21ef-6499-7d79-87b4-04cfcae7aa46" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_019e21ef-6499-76d9-8383-d8deea2873bd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTable_019e21ef-6499-7d79-87b4-04cfcae7aa46" xlink:to="loc_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_019e21ef-6499-76d9-8383-d8deea2873bd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivableTypeDomain_019e21ef-6499-76d9-8383-d8deea2873bd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReceivableTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_019e21ef-6499-76d9-8383-d8deea2873bd" xlink:to="loc_us-gaap_ReceivableTypeDomain_019e21ef-6499-76d9-8383-d8deea2873bd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReceivableTypeDomain_019e21ef-6499-7ed2-9edc-6266227f832d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReceivableTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis_019e21ef-6499-76d9-8383-d8deea2873bd" xlink:to="loc_us-gaap_ReceivableTypeDomain_019e21ef-6499-7ed2-9edc-6266227f832d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradeAccountsReceivableMember_019e21ef-6499-7d6c-97fb-48a8af23028d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradeAccountsReceivableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReceivableTypeDomain_019e21ef-6499-7ed2-9edc-6266227f832d" xlink:to="loc_us-gaap_TradeAccountsReceivableMember_019e21ef-6499-7d6c-97fb-48a8af23028d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_UnbilledReceivablesMember_019e21ef-6499-76fe-8c8f-b03a847b6b9b" xlink:href="alk-20260630.xsd#alk_UnbilledReceivablesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ReceivableTypeDomain_019e21ef-6499-7ed2-9edc-6266227f832d" xlink:to="loc_alk_UnbilledReceivablesMember_019e21ef-6499-76fe-8c8f-b03a847b6b9b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableGrossCurrent_019e21ef-6499-7319-bf1f-37ea82c5adc3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableGrossCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e21ef-6499-701f-b879-feef5953555e" xlink:to="loc_us-gaap_AccountsReceivableGrossCurrent_019e21ef-6499-7319-bf1f-37ea82c5adc3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_019e21ef-6499-75c1-8dc2-98ee1bb428a6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e21ef-6499-701f-b879-feef5953555e" xlink:to="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_019e21ef-6499-75c1-8dc2-98ee1bb428a6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_AccountsReceivableEstimatedCreditsReserveCurrent_019e21ef-6499-7be3-b65c-89338785b558" xlink:href="alk-20260630.xsd#alk_AccountsReceivableEstimatedCreditsReserveCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e21ef-6499-701f-b879-feef5953555e" xlink:to="loc_alk_AccountsReceivableEstimatedCreditsReserveCurrent_019e21ef-6499-7be3-b65c-89338785b558" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_019e21ef-6499-744f-9cfa-56f523c33593" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_019e21ef-6499-701f-b879-feef5953555e" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_019e21ef-6499-744f-9cfa-56f523c33593" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/DebtNarrativeDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#DebtNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/DebtNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019e21ef-6499-7b3f-a67b-0167de027c3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:to="loc_us-gaap_CreditFacilityAxis_019e21ef-6499-7b3f-a67b-0167de027c3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e21ef-6499-7b3f-a67b-0167de027c3a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019e21ef-6499-7b3f-a67b-0167de027c3a" xlink:to="loc_us-gaap_CreditFacilityDomain_019e21ef-6499-7b3f-a67b-0167de027c3a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e21ef-6499-7ab6-a897-eb1ae76394bb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019e21ef-6499-7b3f-a67b-0167de027c3a" xlink:to="loc_us-gaap_CreditFacilityDomain_019e21ef-6499-7ab6-a897-eb1ae76394bb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_019e21ef-6499-7e33-8d9e-a99bceb3db8b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e21ef-6499-7ab6-a897-eb1ae76394bb" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_019e21ef-6499-7e33-8d9e-a99bceb3db8b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-7ed3-ab84-6513d0495780" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:to="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-7ed3-ab84-6513d0495780" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-7ed3-ab84-6513d0495780_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-7ed3-ab84-6513d0495780" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-7ed3-ab84-6513d0495780_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-767a-b87c-c92c4d4e1de0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-7ed3-ab84-6513d0495780" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-767a-b87c-c92c4d4e1de0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_ThirdAmendmentMember_019e21ef-6499-77a9-82ea-999d7581a14d" xlink:href="alk-20260630.xsd#alk_ThirdAmendmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-767a-b87c-c92c4d4e1de0" xlink:to="loc_alk_ThirdAmendmentMember_019e21ef-6499-77a9-82ea-999d7581a14d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_AmendedCreditAgreementMember_019e21ef-6499-75cf-ac92-6338bd2997ce" xlink:href="alk-20260630.xsd#alk_AmendedCreditAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-767a-b87c-c92c4d4e1de0" xlink:to="loc_alk_AmendedCreditAgreementMember_019e21ef-6499-75cf-ac92-6338bd2997ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_A2030ConvertibleNotesMember_019e21ef-6499-7dd0-9b42-0b284e01ec83" xlink:href="alk-20260630.xsd#alk_A2030ConvertibleNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-767a-b87c-c92c4d4e1de0" xlink:to="loc_alk_A2030ConvertibleNotesMember_019e21ef-6499-7dd0-9b42-0b284e01ec83" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_FourthAmendmentMember_019f8032-7003-714d-8fc7-9573bbe901ba" xlink:href="alk-20260630.xsd#alk_FourthAmendmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-767a-b87c-c92c4d4e1de0" xlink:to="loc_alk_FourthAmendmentMember_019f8032-7003-714d-8fc7-9573bbe901ba" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_FifthAmendmentMember_019f8035-513f-7815-90a7-38599d6d06ae" xlink:href="alk-20260630.xsd#alk_FifthAmendmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-767a-b87c-c92c4d4e1de0" xlink:to="loc_alk_FifthAmendmentMember_019f8035-513f-7815-90a7-38599d6d06ae" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-75eb-98ce-c69a1d2e4d67" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-75eb-98ce-c69a1d2e4d67" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-75eb-98ce-c69a1d2e4d67_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-75eb-98ce-c69a1d2e4d67" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-75eb-98ce-c69a1d2e4d67_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7f1c-a29f-3e6e30929c46" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-75eb-98ce-c69a1d2e4d67" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7f1c-a29f-3e6e30929c46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019e21ef-6499-72d6-bc7b-b4298f275e06" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7f1c-a29f-3e6e30929c46" xlink:to="loc_us-gaap_LineOfCreditMember_019e21ef-6499-72d6-bc7b-b4298f275e06" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleNotesPayableMember_019e21ef-6499-7a8d-81eb-a8c28a7183b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleNotesPayableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7f1c-a29f-3e6e30929c46" xlink:to="loc_us-gaap_ConvertibleNotesPayableMember_019e21ef-6499-7a8d-81eb-a8c28a7183b2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtMember_019e21ef-6499-7098-8dc8-c5eedc983f94" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7f1c-a29f-3e6e30929c46" xlink:to="loc_us-gaap_ConvertibleDebtMember_019e21ef-6499-7098-8dc8-c5eedc983f94" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019e21ef-6499-79b6-a105-fc766451f19c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:to="loc_srt_RangeAxis_019e21ef-6499-79b6-a105-fc766451f19c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e21ef-6499-79b6-a105-fc766451f19c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019e21ef-6499-79b6-a105-fc766451f19c" xlink:to="loc_srt_RangeMember_019e21ef-6499-79b6-a105-fc766451f19c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e21ef-6499-75cb-a336-3f4b2258462f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019e21ef-6499-79b6-a105-fc766451f19c" xlink:to="loc_srt_RangeMember_019e21ef-6499-75cb-a336-3f4b2258462f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019e21ef-6499-7e86-80a0-a6b9f31aab01" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e21ef-6499-75cb-a336-3f4b2258462f" xlink:to="loc_srt_MinimumMember_019e21ef-6499-7e86-80a0-a6b9f31aab01" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019e21ef-6499-78f0-b5a0-7d60ccc2e288" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e21ef-6499-75cb-a336-3f4b2258462f" xlink:to="loc_srt_MaximumMember_019e21ef-6499-78f0-b5a0-7d60ccc2e288" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_019e21ef-6499-7245-ae65-a1d62a9269de" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_019e21ef-6499-7245-ae65-a1d62a9269de" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_019e21ef-6499-7245-ae65-a1d62a9269de_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_019e21ef-6499-7245-ae65-a1d62a9269de" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_019e21ef-6499-7245-ae65-a1d62a9269de_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_019e21ef-6499-7775-a622-709591265ca6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis_019e21ef-6499-7245-ae65-a1d62a9269de" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_019e21ef-6499-7775-a622-709591265ca6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodOneMember_019e21ef-6499-7b71-b2df-5ca56876fea4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_019e21ef-6499-7775-a622-709591265ca6" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodOneMember_019e21ef-6499-7b71-b2df-5ca56876fea4" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodTwoMember_019e21ef-6499-7579-bc13-ba5b83e3f6c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_019e21ef-6499-7775-a622-709591265ca6" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodTwoMember_019e21ef-6499-7579-bc13-ba5b83e3f6c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodThreeMember_019e21ef-6499-75d7-9352-a5bcf02cbcb6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain_019e21ef-6499-7775-a622-709591265ca6" xlink:to="loc_us-gaap_DebtInstrumentRedemptionPeriodThreeMember_019e21ef-6499-75d7-9352-a5bcf02cbcb6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentConvertibleTermsOfConversionAxis_019e21ef-6499-7f05-b086-78ad25db8432" xlink:href="alk-20260630.xsd#alk_DebtInstrumentConvertibleTermsOfConversionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:to="loc_alk_DebtInstrumentConvertibleTermsOfConversionAxis_019e21ef-6499-7f05-b086-78ad25db8432" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentConvertibleTermsOfConversionDomain_019e21ef-6499-7f05-b086-78ad25db8432_default" xlink:href="alk-20260630.xsd#alk_DebtInstrumentConvertibleTermsOfConversionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_alk_DebtInstrumentConvertibleTermsOfConversionAxis_019e21ef-6499-7f05-b086-78ad25db8432" xlink:to="loc_alk_DebtInstrumentConvertibleTermsOfConversionDomain_019e21ef-6499-7f05-b086-78ad25db8432_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentConvertibleTermsOfConversionDomain_019e21ef-6499-7108-a406-eb1f98b507ba" xlink:href="alk-20260630.xsd#alk_DebtInstrumentConvertibleTermsOfConversionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_alk_DebtInstrumentConvertibleTermsOfConversionAxis_019e21ef-6499-7f05-b086-78ad25db8432" xlink:to="loc_alk_DebtInstrumentConvertibleTermsOfConversionDomain_019e21ef-6499-7108-a406-eb1f98b507ba" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtConversionTermsOneMember_019e21ef-6499-71f4-b1de-de9e44793e14" xlink:href="alk-20260630.xsd#alk_DebtConversionTermsOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_alk_DebtInstrumentConvertibleTermsOfConversionDomain_019e21ef-6499-7108-a406-eb1f98b507ba" xlink:to="loc_alk_DebtConversionTermsOneMember_019e21ef-6499-71f4-b1de-de9e44793e14" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtConversionTermsTwoMember_019e21ef-6499-756b-8a8e-78d19fd8d47b" xlink:href="alk-20260630.xsd#alk_DebtConversionTermsTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_alk_DebtInstrumentConvertibleTermsOfConversionDomain_019e21ef-6499-7108-a406-eb1f98b507ba" xlink:to="loc_alk_DebtConversionTermsTwoMember_019e21ef-6499-756b-8a8e-78d19fd8d47b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e21ef-6499-7c4e-95a6-1d7b319afb24" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-73b0-919c-a0e8c3888241" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e21ef-6499-7c4e-95a6-1d7b319afb24" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e21ef-6499-7c4e-95a6-1d7b319afb24_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e21ef-6499-7c4e-95a6-1d7b319afb24" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e21ef-6499-7c4e-95a6-1d7b319afb24_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingRelationshipDomain_019e21ef-6499-7234-a67a-88ed34b52ba1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingRelationshipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_019e21ef-6499-7c4e-95a6-1d7b319afb24" xlink:to="loc_us-gaap_HedgingRelationshipDomain_019e21ef-6499-7234-a67a-88ed34b52ba1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeMember_019e21ef-6499-7e44-8a4b-dc0b104835b3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_019e21ef-6499-7234-a67a-88ed34b52ba1" xlink:to="loc_us-gaap_DerivativeMember_019e21ef-6499-7e44-8a4b-dc0b104835b3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityIncreaseDecreaseForPeriodNet_019e21ef-6499-7865-92bc-8ee69dbeb03a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityIncreaseDecreaseForPeriodNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_LineOfCreditFacilityIncreaseDecreaseForPeriodNet_019e21ef-6499-7865-92bc-8ee69dbeb03a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019e21ef-6499-7b60-baa6-9fbe9271ac94" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019e21ef-6499-7b60-baa6-9fbe9271ac94" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_019e21ef-6499-7e1f-a213-322690af5bd6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_019e21ef-6499-7e1f-a213-322690af5bd6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_019e21ef-6499-7a54-a730-d52c38ba3ba0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_LongTermDebt_019e21ef-6499-7a54-a730-d52c38ba3ba0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_019e21ef-6499-7f57-8542-c2a7830b8099" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_019e21ef-6499-7f57-8542-c2a7830b8099" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_019e21ef-6499-7b73-a754-a88e31adaf3c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_InterestExpenseDebt_019e21ef-6499-7b73-a754-a88e31adaf3c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentCovenantRevenueGrowthRequirementPercent_019e21ef-6499-7e01-b27e-30322d8f3263" xlink:href="alk-20260630.xsd#alk_DebtInstrumentCovenantRevenueGrowthRequirementPercent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DebtInstrumentCovenantRevenueGrowthRequirementPercent_019e21ef-6499-7e01-b27e-30322d8f3263" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentCovenantLiquidityRequirement_019e21ef-6499-7b3c-bfe2-bb5bf6a42974" xlink:href="alk-20260630.xsd#alk_DebtInstrumentCovenantLiquidityRequirement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DebtInstrumentCovenantLiquidityRequirement_019e21ef-6499-7b3c-bfe2-bb5bf6a42974" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentCovenantLeverageRatioMaximum_019e21ef-6499-7f1b-99ba-5712d2c2dea8" xlink:href="alk-20260630.xsd#alk_DebtInstrumentCovenantLeverageRatioMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DebtInstrumentCovenantLeverageRatioMaximum_019e21ef-6499-7f1b-99ba-5712d2c2dea8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentCovenantInterestCoverageRatioMinimum_019e21ef-6499-7917-8c3e-642352c38f5e" xlink:href="alk-20260630.xsd#alk_DebtInstrumentCovenantInterestCoverageRatioMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DebtInstrumentCovenantInterestCoverageRatioMinimum_019e21ef-6499-7917-8c3e-642352c38f5e" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentCovenantRequiredFreeCashFlow_019e21ef-6499-76f4-83bf-fc5834c2b897" xlink:href="alk-20260630.xsd#alk_DebtInstrumentCovenantRequiredFreeCashFlow"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DebtInstrumentCovenantRequiredFreeCashFlow_019e21ef-6499-76f4-83bf-fc5834c2b897" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentCovenantCashRequirements_019f900a-9cfb-7e81-ac91-39725e9d6ce6" xlink:href="alk-20260630.xsd#alk_DebtInstrumentCovenantCashRequirements"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DebtInstrumentCovenantCashRequirements_019f900a-9cfb-7e81-ac91-39725e9d6ce6" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentCovenantFundsAvailableToRepurchaseCommonStock_019f900f-7223-7fd0-8668-edcf40743144" xlink:href="alk-20260630.xsd#alk_DebtInstrumentCovenantFundsAvailableToRepurchaseCommonStock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DebtInstrumentCovenantFundsAvailableToRepurchaseCommonStock_019f900f-7223-7fd0-8668-edcf40743144" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_019e21ef-6499-7f9a-a88a-3a09154d0b97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_019e21ef-6499-7f9a-a88a-3a09154d0b97" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019e21ef-6499-7c5a-84ff-a2f780282af7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019e21ef-6499-7c5a-84ff-a2f780282af7" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionRatio1_019e21ef-6499-78ac-bf05-2bc629c63a34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentConvertibleConversionRatio1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentConvertibleConversionRatio1_019e21ef-6499-78ac-bf05-2bc629c63a34" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_019e21ef-6499-7372-ba9a-6ab6aebdb482" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentConvertibleConversionPrice1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentConvertibleConversionPrice1_019e21ef-6499-7372-ba9a-6ab6aebdb482" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_019e21ef-6499-7727-9138-807493bb084d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdPercentageOfStockPriceTrigger_019e21ef-6499-7727-9138-807493bb084d" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdTradingDays_019e21ef-6499-7059-ae53-94525fb2eeab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentConvertibleThresholdTradingDays"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdTradingDays_019e21ef-6499-7059-ae53-94525fb2eeab" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_019f9039-ba9f-7617-8575-5332820c1b1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentConvertibleThresholdConsecutiveTradingDays1_019f9039-ba9f-7617-8575-5332820c1b1f" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DebtInstrumentConvertibleMinimumAggregatePrincipalAmountOutstanding_019e21ef-6499-74bd-a5a6-9c1f5a00e9cd" xlink:href="alk-20260630.xsd#alk_DebtInstrumentConvertibleMinimumAggregatePrincipalAmountOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DebtInstrumentConvertibleMinimumAggregatePrincipalAmountOutstanding_019e21ef-6499-74bd-a5a6-9c1f5a00e9cd" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_019e21ef-6499-791e-85c0-eb1e699ee81c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_019e21ef-6499-791e-85c0-eb1e699ee81c" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLiabilities_019e21ef-6499-76b8-accb-6167e1446bfa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_DerivativeLiabilities_019e21ef-6499-76b8-accb-6167e1446bfa" xlink:type="arc" order="22"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquity_019e21ef-6499-7544-9bee-02b018bf8c05" xlink:href="alk-20260630.xsd#alk_AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_AdjustmentsToAdditionalPaidInCapitalOptionIndexedToIssuersEquity_019e21ef-6499-7544-9bee-02b018bf8c05" xlink:type="arc" order="23"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OptionIndexedToIssuersEquityStrikePrice1_019e21ef-6499-7ba0-843e-20ef3e1518af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OptionIndexedToIssuersEquityStrikePrice1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_us-gaap_OptionIndexedToIssuersEquityStrikePrice1_019e21ef-6499-7ba0-843e-20ef3e1518af" xlink:type="arc" order="24"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_DerivativesInitialCapPrice_019e21ef-6499-7193-8807-ac86c217d703" xlink:href="alk-20260630.xsd#alk_DerivativesInitialCapPrice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7334-98ea-544d9340fdd2" xlink:to="loc_alk_DerivativesInitialCapPrice_019e21ef-6499-7193-8807-ac86c217d703" xlink:type="arc" order="25"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/DebtScheduleofLongTermDebtDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#DebtScheduleofLongTermDebtDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/DebtScheduleofLongTermDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7bfc-bdf1-5c12d6b5126e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-72f3-a90c-ee3c1e7f7b8e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7bfc-bdf1-5c12d6b5126e" xlink:to="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-72f3-a90c-ee3c1e7f7b8e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-7f3a-9796-e9cf1612c237" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-72f3-a90c-ee3c1e7f7b8e" xlink:to="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-7f3a-9796-e9cf1612c237" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-7f3a-9796-e9cf1612c237_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-7f3a-9796-e9cf1612c237" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-7f3a-9796-e9cf1612c237_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-7a57-9e3c-ccc5017c6087" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-7f3a-9796-e9cf1612c237" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-7a57-9e3c-ccc5017c6087" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_A2030ConvertibleNotesMember_019e21ef-6499-774f-87db-662aeff35793" xlink:href="alk-20260630.xsd#alk_A2030ConvertibleNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-7a57-9e3c-ccc5017c6087" xlink:to="loc_alk_A2030ConvertibleNotesMember_019e21ef-6499-774f-87db-662aeff35793" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-7997-9456-fe6c6e670133" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-72f3-a90c-ee3c1e7f7b8e" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-7997-9456-fe6c6e670133" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7997-9456-fe6c6e670133_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-7997-9456-fe6c6e670133" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7997-9456-fe6c6e670133_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7c8c-9318-fcf9d0affc4c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-7997-9456-fe6c6e670133" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7c8c-9318-fcf9d0affc4c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleNotesPayableMember_019e21ef-6499-75b4-a089-03c04ecb9709" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleNotesPayableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7c8c-9318-fcf9d0affc4c" xlink:to="loc_us-gaap_ConvertibleNotesPayableMember_019e21ef-6499-75b4-a089-03c04ecb9709" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019e21ef-6499-739e-9e8e-ca8df957d616" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7bfc-bdf1-5c12d6b5126e" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_019e21ef-6499-739e-9e8e-ca8df957d616" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscount_019e21ef-6499-74fb-8a4a-3e71bb8832bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentUnamortizedDiscount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7bfc-bdf1-5c12d6b5126e" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscount_019e21ef-6499-74fb-8a4a-3e71bb8832bc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_019e21ef-6499-7290-8426-a6c493b75a0a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredFinanceCostsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7bfc-bdf1-5c12d6b5126e" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_019e21ef-6499-7290-8426-a6c493b75a0a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebt_019e21ef-6499-733c-aa14-31c0f688af0c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7bfc-bdf1-5c12d6b5126e" xlink:to="loc_us-gaap_LongTermDebt_019e21ef-6499-733c-aa14-31c0f688af0c" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/DebtScheduleofDebtDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#DebtScheduleofDebtDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/DebtScheduleofDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7fa1-a695-9b4b5c7c633b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-70fa-acf8-0426fd49bb32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7fa1-a695-9b4b5c7c633b" xlink:to="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-70fa-acf8-0426fd49bb32" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-78a8-812c-65b3b2026229" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-70fa-acf8-0426fd49bb32" xlink:to="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-78a8-812c-65b3b2026229" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-78a8-812c-65b3b2026229_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-78a8-812c-65b3b2026229" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-78a8-812c-65b3b2026229_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-765b-8f43-31ad271aeae3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e21ef-6499-78a8-812c-65b3b2026229" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-765b-8f43-31ad271aeae3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_A2030ConvertibleNotesMember_019e21ef-6499-7691-9d50-0469c86606ce" xlink:href="alk-20260630.xsd#alk_A2030ConvertibleNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e21ef-6499-765b-8f43-31ad271aeae3" xlink:to="loc_alk_A2030ConvertibleNotesMember_019e21ef-6499-7691-9d50-0469c86606ce" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-7f1c-bd71-ed03e4e4f3b6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e21ef-6499-70fa-acf8-0426fd49bb32" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-7f1c-bd71-ed03e4e4f3b6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7f1c-bd71-ed03e4e4f3b6_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-7f1c-bd71-ed03e4e4f3b6" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-7f1c-bd71-ed03e4e4f3b6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-73e4-bb4a-78c92dbd2ef3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e21ef-6499-7f1c-bd71-ed03e4e4f3b6" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-73e4-bb4a-78c92dbd2ef3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleNotesPayableMember_019e21ef-6499-70e0-a7a9-d26b891724c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleNotesPayableMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e21ef-6499-73e4-bb4a-78c92dbd2ef3" xlink:to="loc_us-gaap_ConvertibleNotesPayableMember_019e21ef-6499-70e0-a7a9-d26b891724c3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebtExcludingAmortization_019e21ef-6499-7e75-b11b-42accf0b94ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseDebtExcludingAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7fa1-a695-9b4b5c7c633b" xlink:to="loc_us-gaap_InterestExpenseDebtExcludingAmortization_019e21ef-6499-7e75-b11b-42accf0b94ee" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_019e21ef-6499-766f-9584-151be51d3d97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfFinancingCostsAndDiscounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7fa1-a695-9b4b5c7c633b" xlink:to="loc_us-gaap_AmortizationOfFinancingCostsAndDiscounts_019e21ef-6499-766f-9584-151be51d3d97" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpenseDebt_019e21ef-6499-7e0f-a600-aa7e311ee092" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e21ef-6499-7fa1-a695-9b4b5c7c633b" xlink:to="loc_us-gaap_InterestExpenseDebt_019e21ef-6499-7e0f-a600-aa7e311ee092" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/StockholdersEquityScheduleofStockbasedCompensationExpenseDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#StockholdersEquityScheduleofStockbasedCompensationExpenseDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/StockholdersEquityScheduleofStockbasedCompensationExpenseDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019e21ef-6499-7e34-b94e-9b4d50745bfa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019e21ef-6499-7b46-95b0-cd816dc3bd3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019e21ef-6499-7e34-b94e-9b4d50745bfa" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019e21ef-6499-7b46-95b0-cd816dc3bd3e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e21ef-6499-7791-ba04-3f16a1b86e0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019e21ef-6499-7b46-95b0-cd816dc3bd3e" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e21ef-6499-7791-ba04-3f16a1b86e0e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e21ef-6499-77aa-ba82-c8eeb4616cd9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019e21ef-6499-7e34-b94e-9b4d50745bfa" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e21ef-6499-77aa-ba82-c8eeb4616cd9" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/StockholdersEquityScheduleofStockbasedCompensationExpenseDetails_1" xlink:type="simple" xlink:href="alk-20260630.xsd#StockholdersEquityScheduleofStockbasedCompensationExpenseDetails_1"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/StockholdersEquityScheduleofStockbasedCompensationExpenseDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019e21ef-6499-7e34-b94e-9b4d50745bfa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019e21ef-6499-7b46-95b0-cd816dc3bd3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019e21ef-6499-7e34-b94e-9b4d50745bfa" xlink:to="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_019e21ef-6499-7b46-95b0-cd816dc3bd3e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e21ef-6499-77aa-ba82-c8eeb4616cd9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_019e21ef-6499-7e34-b94e-9b4d50745bfa" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e21ef-6499-77aa-ba82-c8eeb4616cd9" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/StockholdersEquityNarrativeDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#StockholdersEquityNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/StockholdersEquityNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e21ef-6499-721f-8d7b-a01222ee4200" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e21ef-6499-7930-8138-d9e8316cc5a0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e21ef-6499-721f-8d7b-a01222ee4200" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e21ef-6499-7930-8138-d9e8316cc5a0" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_019e21ef-6499-7ce5-bfb9-602422313264" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_019e21ef-6499-7930-8138-d9e8316cc5a0" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_019e21ef-6499-7ce5-bfb9-602422313264" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e21ef-6499-7ce5-bfb9-602422313264_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e21ef-6499-7ce5-bfb9-602422313264" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e21ef-6499-7ce5-bfb9-602422313264_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e21ef-6499-7ff2-95b7-9ae174b45ad7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_019e21ef-6499-7ce5-bfb9-602422313264" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e21ef-6499-7ff2-95b7-9ae174b45ad7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_MANTLMember_019e21ef-6499-73e3-9e24-fe0e8ef6a277" xlink:href="alk-20260630.xsd#alk_MANTLMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_019e21ef-6499-7ff2-95b7-9ae174b45ad7" xlink:to="loc_alk_MANTLMember_019e21ef-6499-73e3-9e24-fe0e8ef6a277" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e21ef-6499-71ed-b6e5-5da7028b56c9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e21ef-6499-721f-8d7b-a01222ee4200" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e21ef-6499-71ed-b6e5-5da7028b56c9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019f82e5-9fdd-7732-be86-2bb92e669bc5" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e21ef-6499-721f-8d7b-a01222ee4200" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019f82e5-9fdd-7732-be86-2bb92e669bc5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_019fa4f2-3e3e-7b8e-b4fa-54c604e38b3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e21ef-6499-721f-8d7b-a01222ee4200" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_019fa4f2-3e3e-7b8e-b4fa-54c604e38b3e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_019fa4f1-115c-7de4-b842-6378ed30823e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e21ef-6499-721f-8d7b-a01222ee4200" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_019fa4f1-115c-7de4-b842-6378ed30823e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_019f9015-7ee0-7ad0-885e-6a5618fc5817" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_019e21ef-6499-721f-8d7b-a01222ee4200" xlink:to="loc_us-gaap_StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1_019f9015-7ee0-7ad0-885e-6a5618fc5817" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/FairValueofFinancialInstrumentsDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#FairValueofFinancialInstrumentsDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/FairValueofFinancialInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e21ef-656c-7209-ada7-e9d554426bf8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e21ef-656c-7318-8b81-e0930b746eee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e21ef-656c-7209-ada7-e9d554426bf8" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e21ef-656c-7318-8b81-e0930b746eee" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAxis_019e21ef-656c-7ba1-8948-282a6fa76636" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e21ef-656c-7318-8b81-e0930b746eee" xlink:to="loc_us-gaap_CashAndCashEquivalentsAxis_019e21ef-656c-7ba1-8948-282a6fa76636" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019e21ef-656c-7ba1-8948-282a6fa76636_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_019e21ef-656c-7ba1-8948-282a6fa76636" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019e21ef-656c-7ba1-8948-282a6fa76636_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019e21ef-656c-7790-b012-3494ad96868a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CashAndCashEquivalentsAxis_019e21ef-656c-7ba1-8948-282a6fa76636" xlink:to="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019e21ef-656c-7790-b012-3494ad96868a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashEquivalentsMember_019e21ef-656c-7ac2-a6e8-18e9b9a6737b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashEquivalentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestrictedCashAndCashEquivalentsCashAndCashEquivalentsMember_019e21ef-656c-7790-b012-3494ad96868a" xlink:to="loc_us-gaap_CashEquivalentsMember_019e21ef-656c-7ac2-a6e8-18e9b9a6737b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e21ef-656c-7e3b-926b-7bfd4bbc5e88" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e21ef-656c-7318-8b81-e0930b746eee" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e21ef-656c-7e3b-926b-7bfd4bbc5e88" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e21ef-656c-7e3b-926b-7bfd4bbc5e88_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e21ef-656c-7e3b-926b-7bfd4bbc5e88" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e21ef-656c-7e3b-926b-7bfd4bbc5e88_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e21ef-656c-7353-9b16-4e09763478e9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e21ef-656c-7e3b-926b-7bfd4bbc5e88" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e21ef-656c-7353-9b16-4e09763478e9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019e21ef-656c-782e-aa48-ea4dee2adc58" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e21ef-656c-7353-9b16-4e09763478e9" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019e21ef-656c-782e-aa48-ea4dee2adc58" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019e21ef-656c-747d-ac33-6a3f63e8943b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e21ef-656c-7353-9b16-4e09763478e9" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019e21ef-656c-747d-ac33-6a3f63e8943b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e21ef-656c-7eb7-a5fc-6d3b09fea13c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e21ef-656c-7353-9b16-4e09763478e9" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e21ef-656c-7eb7-a5fc-6d3b09fea13c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019e21ef-656c-70ad-8b97-baafc180bf13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e21ef-656c-7318-8b81-e0930b746eee" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019e21ef-656c-70ad-8b97-baafc180bf13" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e21ef-656c-70ad-8b97-baafc180bf13_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e21ef-656c-70ad-8b97-baafc180bf13" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e21ef-656c-70ad-8b97-baafc180bf13_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e21ef-656c-775b-8057-ef6e41e9d088" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019e21ef-656c-70ad-8b97-baafc180bf13" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e21ef-656c-775b-8057-ef6e41e9d088" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateBondSecuritiesMember_019e21ef-656c-77d5-8989-ec308afb8d9b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateBondSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e21ef-656c-775b-8057-ef6e41e9d088" xlink:to="loc_us-gaap_CorporateBondSecuritiesMember_019e21ef-656c-77d5-8989-ec308afb8d9b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommercialPaperMember_019e21ef-656c-7a34-a5df-4be5ce494d6b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommercialPaperMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e21ef-656c-775b-8057-ef6e41e9d088" xlink:to="loc_us-gaap_CommercialPaperMember_019e21ef-656c-7a34-a5df-4be5ce494d6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_USTreasurySecuritiesMember_019e21ef-656c-76e3-aa49-48729914fb32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_USTreasurySecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e21ef-656c-775b-8057-ef6e41e9d088" xlink:to="loc_us-gaap_USTreasurySecuritiesMember_019e21ef-656c-76e3-aa49-48729914fb32" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_InternationalDebtSecuritiesMember_019e21ef-656c-7af8-b6e0-80a8f86e2454" xlink:href="alk-20260630.xsd#alk_InternationalDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019e21ef-656c-775b-8057-ef6e41e9d088" xlink:to="loc_alk_InternationalDebtSecuritiesMember_019e21ef-656c-7af8-b6e0-80a8f86e2454" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e21ef-656c-78dc-ab0b-5a709df26812" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e21ef-656c-7209-ada7-e9d554426bf8" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e21ef-656c-78dc-ab0b-5a709df26812" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019e21ef-656c-7f22-926f-6dbc9e59c631" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e21ef-656c-78dc-ab0b-5a709df26812" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019e21ef-656c-7f22-926f-6dbc9e59c631" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradingSecuritiesDebt_019e21ef-656c-71a2-95fa-1eabd965261c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradingSecuritiesDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e21ef-656c-78dc-ab0b-5a709df26812" xlink:to="loc_us-gaap_TradingSecuritiesDebt_019e21ef-656c-71a2-95fa-1eabd965261c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_019e21ef-656c-7d13-8ed0-c597a56c7f0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e21ef-656c-78dc-ab0b-5a709df26812" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_019e21ef-656c-7d13-8ed0-c597a56c7f0e" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/EarningsPerShareScheduleofAntidilutiveSecuritiesDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#EarningsPerShareScheduleofAntidilutiveSecuritiesDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/EarningsPerShareScheduleofAntidilutiveSecuritiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e21ef-656c-76e5-824f-c823dc7d6e0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e21ef-656c-7381-8cd0-ecb02f69a984" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e21ef-656c-76e5-824f-c823dc7d6e0e" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e21ef-656c-7381-8cd0-ecb02f69a984" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e21ef-656c-7adc-9b8b-754f361ddf69" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e21ef-656c-7381-8cd0-ecb02f69a984" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e21ef-656c-7adc-9b8b-754f361ddf69" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e21ef-656c-7adc-9b8b-754f361ddf69_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e21ef-656c-7adc-9b8b-754f361ddf69" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e21ef-656c-7adc-9b8b-754f361ddf69_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e21ef-656c-79bf-9926-8b8c10e9d6e4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e21ef-656c-7adc-9b8b-754f361ddf69" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e21ef-656c-79bf-9926-8b8c10e9d6e4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019e21ef-656c-7c21-91dd-67963aad47fe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e21ef-656c-79bf-9926-8b8c10e9d6e4" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019e21ef-656c-7c21-91dd-67963aad47fe" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019e21ef-656c-7641-84e7-f7cb23143cfc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e21ef-656c-79bf-9926-8b8c10e9d6e4" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019e21ef-656c-7641-84e7-f7cb23143cfc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockMember_019e21ef-656c-77dc-85c5-27baf520d8b3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e21ef-656c-79bf-9926-8b8c10e9d6e4" xlink:to="loc_us-gaap_EmployeeStockMember_019e21ef-656c-77dc-85c5-27baf520d8b3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_alk_A2030ConvertibleNotesMember_019e21ef-656c-72d4-b47e-7b2d92bdea76" xlink:href="alk-20260630.xsd#alk_A2030ConvertibleNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e21ef-656c-79bf-9926-8b8c10e9d6e4" xlink:to="loc_alk_A2030ConvertibleNotesMember_019e21ef-656c-72d4-b47e-7b2d92bdea76" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_019e21ef-656c-756e-b806-09a8285f129b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e21ef-656c-76e5-824f-c823dc7d6e0e" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_019e21ef-656c-756e-b806-09a8285f129b" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/GoodwillandOtherIntangiblesScheduleofTotalIntangiblesNetDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#GoodwillandOtherIntangiblesScheduleofTotalIntangiblesNetDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/GoodwillandOtherIntangiblesScheduleofTotalIntangiblesNetDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019e21ef-656c-7744-b96a-d65ae17d10b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019e21ef-656c-72c2-8cf3-1c6af3d66538" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019e21ef-656c-7744-b96a-d65ae17d10b7" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019e21ef-656c-72c2-8cf3-1c6af3d66538" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019e21ef-656c-791c-8599-dfdfba15c99d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_019e21ef-656c-72c2-8cf3-1c6af3d66538" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019e21ef-656c-791c-8599-dfdfba15c99d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-656c-791c-8599-dfdfba15c99d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019e21ef-656c-791c-8599-dfdfba15c99d" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-656c-791c-8599-dfdfba15c99d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-656c-7565-b80e-49c410a186ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_019e21ef-656c-791c-8599-dfdfba15c99d" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-656c-7565-b80e-49c410a186ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CustomerRelationshipsMember_019e21ef-656c-7578-afbd-1a491bd09403" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CustomerRelationshipsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-656c-7565-b80e-49c410a186ee" xlink:to="loc_us-gaap_CustomerRelationshipsMember_019e21ef-656c-7578-afbd-1a491bd09403" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_019e21ef-656c-70c3-b398-5cb3b0b41baf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DevelopedTechnologyRightsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-656c-7565-b80e-49c410a186ee" xlink:to="loc_us-gaap_DevelopedTechnologyRightsMember_019e21ef-656c-70c3-b398-5cb3b0b41baf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradeNamesMember_019e21ef-656c-7078-9588-35d2a366d451" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_019e21ef-656c-7565-b80e-49c410a186ee" xlink:to="loc_us-gaap_TradeNamesMember_019e21ef-656c-7078-9588-35d2a366d451" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019e21ef-656c-75a9-ab86-8609f0d343d0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019e21ef-656c-7744-b96a-d65ae17d10b7" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_019e21ef-656c-75a9-ab86-8609f0d343d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019e21ef-656c-7a2a-9ce6-275a68e20dd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019e21ef-656c-7744-b96a-d65ae17d10b7" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_019e21ef-656c-7a2a-9ce6-275a68e20dd4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019e21ef-656c-7935-961f-7a5c2054c3b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019e21ef-656c-7744-b96a-d65ae17d10b7" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_019e21ef-656c-7935-961f-7a5c2054c3b1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_019e21ef-656c-7280-96f3-e55d7120f99b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019e21ef-656c-7744-b96a-d65ae17d10b7" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsExcludingGoodwill_019e21ef-656c-7280-96f3-e55d7120f99b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019e21ef-656c-74a8-af11-60a75ef4fa53" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsGrossExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019e21ef-656c-7744-b96a-d65ae17d10b7" xlink:to="loc_us-gaap_IntangibleAssetsGrossExcludingGoodwill_019e21ef-656c-74a8-af11-60a75ef4fa53" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e21ef-656c-78d9-8327-e261454af446" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_019e21ef-656c-7744-b96a-d65ae17d10b7" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_019e21ef-656c-78d9-8327-e261454af446" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.alkami.com/role/SubsequentEventDetails" xlink:type="simple" xlink:href="alk-20260630.xsd#SubsequentEventDetails"/>
  <link:definitionLink xlink:role="http://www.alkami.com/role/SubsequentEventDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventLineItems_019e21ef-656c-76e7-9552-8248ece3d27e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTable_019e21ef-656c-7efb-88f6-7a53c24e4aeb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SubsequentEventLineItems_019e21ef-656c-76e7-9552-8248ece3d27e" xlink:to="loc_us-gaap_SubsequentEventTable_019e21ef-656c-7efb-88f6-7a53c24e4aeb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_019e21ef-656c-706b-bcbf-5d8805195c3d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_SubsequentEventTable_019e21ef-656c-7efb-88f6-7a53c24e4aeb" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_019e21ef-656c-706b-bcbf-5d8805195c3d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019e21ef-656c-706b-bcbf-5d8805195c3d_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019e21ef-656c-706b-bcbf-5d8805195c3d" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019e21ef-656c-706b-bcbf-5d8805195c3d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_019e21ef-656c-721c-960d-87a4907a79c6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_019e21ef-656c-706b-bcbf-5d8805195c3d" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_019e21ef-656c-721c-960d-87a4907a79c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SubsequentEventMember_019e21ef-656c-7eb8-ab16-4896350fdc52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_019e21ef-656c-721c-960d-87a4907a79c6" xlink:to="loc_us-gaap_SubsequentEventMember_019e21ef-656c-7eb8-ab16-4896350fdc52" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_019f927e-3377-7f0a-9f55-d9017df58ce8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_019e21ef-656c-76e7-9552-8248ece3d27e" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares_019f927e-3377-7f0a-9f55-d9017df58ce8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_019fa4ef-f565-7098-a1bd-150457cca16f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventLineItems_019e21ef-656c-76e7-9552-8248ece3d27e" xlink:to="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue_019fa4ef-f565-7098-a1bd-150457cca16f" xlink:type="arc" order="1"/>
  </link:definitionLink>
</link:linkbase>
