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  <xsd:element id="xmtr_TwoNewOfficeLeasesInLyonFranceAndIstanbulTurkeyMember" name="TwoNewOfficeLeasesInLyonFranceAndIstanbulTurkeyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="xmtr_ProvisionForEstimatedReturnsRefundsOrAllowances" name="ProvisionForEstimatedReturnsRefundsOrAllowances" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="xmtr_OneTimeAdditionalChargeOfOperatingLeasesRentExpense" name="OneTimeAdditionalChargeOfOperatingLeasesRentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="xmtr_BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesAbstract" name="BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="xmtr_GoodwillAndIntangibleAssetsTable" name="GoodwillAndIntangibleAssetsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="xmtr_NumberOfNewLeases" name="NumberOfNewLeases" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="xmtr_ScheduleOfDepreciationExpensesTableTextBlock" name="ScheduleOfDepreciationExpensesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="xmtr_ScheduleOfRestructuringRelatedEmployeeTerminationBenefitsTableTextBlock" name="ScheduleOfRestructuringRelatedEmployeeTerminationBenefitsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="xmtr_BusinessCombinationInitialFairValueOfContingentConsideration" name="BusinessCombinationInitialFairValueOfContingentConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="xmtr_OperationsAndSupportPolicyTextBlock" name="OperationsAndSupportPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="xmtr_SalesContractAcquisitionCostsMember" name="SalesContractAcquisitionCostsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="xmtr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermExercised" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTermExercised" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="xmtr_ThomasPublishingCompanyMember" name="ThomasPublishingCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="xmtr_ScheduleOfOperatingLeaseExpenseTableTextBlock" name="ScheduleOfOperatingLeaseExpenseTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="xmtr_MarketplaceRevenueMember" name="MarketplaceRevenueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="xmtr_CommonClassAAndClassBMember" name="CommonClassAAndClassBMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="xmtr_OperationsAndSupportExpense" name="OperationsAndSupportExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="xmtr_IncomeLossFromUnconsolidatedJointVenture" name="IncomeLossFromUnconsolidatedJointVenture" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="xmtr_StockIssuedDuringPeriodSharesDonatedCommonStock" name="StockIssuedDuringPeriodSharesDonatedCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="xmtr_NewCustomersMember" name="NewCustomersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
</xsd:schema>
