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  <xsd:import namespace="http://xbrl.sec.gov/ecd/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-2025.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/dei/2025" schemaLocation="https://xbrl.sec.gov/dei/2025/dei-2025.xsd" />
  <xsd:import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <xsd:import namespace="http://fasb.org/us-roles/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-roles-2025.xsd" />
  <xsd:import namespace="http://fasb.org/us-gaap/2025" schemaLocation="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd" />
  <xsd:import namespace="http://fasb.org/srt/2025" schemaLocation="https://xbrl.fasb.org/srt/2025/elts/srt-2025.xsd" />
  <xsd:import namespace="http://xbrl.sec.gov/ecd-sub/2025" schemaLocation="https://xbrl.sec.gov/ecd/2025/ecd-sub-2025.xsd" />
  <xsd:element name="StockSubscriptionReceivableTable" id="cyph_StockSubscriptionReceivableTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockSubscriptionReceivableLineItem" id="cyph_StockSubscriptionReceivableLineItem" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SaleOfStockMaximumValueOfSharesIssuedInTransaction" id="cyph_SaleOfStockMaximumValueOfSharesIssuedInTransaction" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="EquityIncentivePlan2025Member" id="cyph_EquityIncentivePlan2025Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element id="cyph_ResearchAndDevelopmentIncentiveReceivable" name="ResearchAndDevelopmentIncentiveReceivable" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="cyph_IncreaseDecreaseInResearchAndDevelopmentIncentiveReceivable" name="IncreaseDecreaseInResearchAndDevelopmentIncentiveReceivable" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
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  <xsd:element id="cyph_AccruedClinicalTrialsCurrent" name="AccruedClinicalTrialsCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
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  <xsd:element id="cyph_LicenseAndServiceAgreementsMember" name="LicenseAndServiceAgreementsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="cyph_LayeringAxis" name="LayeringAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
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  <xsd:element id="cyph_EquityIncentivePlan2016Member" name="EquityIncentivePlan2016Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="cyph_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedAnnualIncreasePercentage" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorizedAnnualIncreasePercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="cyph_NumberOfVoteOnCommonShares" name="NumberOfVoteOnCommonShares" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="cyph_ResearchAndDevelopmentIncentiveIncomeAndReceivablePolicyTextBlock" name="ResearchAndDevelopmentIncentiveIncomeAndReceivablePolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="cyph_DeferredOfferingCostsPolicyTextBlock" name="DeferredOfferingCostsPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="cyph_ResearchAndDevelopmentIncentiveIncomeAndReceivableAbstract" name="ResearchAndDevelopmentIncentiveIncomeAndReceivableAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="cyph_AustralianResearchAndDevelopmentIncentivePercentExpensesReimbursed" name="AustralianResearchAndDevelopmentIncentivePercentExpensesReimbursed" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="cyph_ResearchAndDevelopmentIncentiveReceivableCurrent" name="ResearchAndDevelopmentIncentiveReceivableCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="cyph_ResearchAndDevelopmentIncentiveIncome" name="ResearchAndDevelopmentIncentiveIncome" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="cyph_ResearchAndDevelopmentIncentiveIncomeAndReceivableRollForward" name="ResearchAndDevelopmentIncentiveIncomeAndReceivableRollForward" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="cyph_ResearchAndDevelopmentIncentiveForeignCurrencyTranslationGainLoss" name="ResearchAndDevelopmentIncentiveForeignCurrencyTranslationGainLoss" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="cyph_ScheduleOfChangeInResearchAndDevelopmentIncentiveReceivableTableTextBlock" name="ScheduleOfChangeInResearchAndDevelopmentIncentiveReceivableTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="cyph_WarrantsDisclosureTextBlock" name="WarrantsDisclosureTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="cyph_DeferredOfferingCostsNoncurrent" name="DeferredOfferingCostsNoncurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="cyph_WarrantsToPurchaseCommonStockMember" name="WarrantsToPurchaseCommonStockMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="cyph_WarrantsExercisableOn23rdJanuary2017Member" name="WarrantsExercisableOn23rdJanuary2017Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="cyph_WarrantsPolicyTextBlock" name="WarrantsPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="cyph_IncreaseDecreaseInLeaseLiabilities" name="IncreaseDecreaseInLeaseLiabilities" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="cyph_StockIssuedDuringPeriodValueExerciseOfPrefundedWarrants" name="StockIssuedDuringPeriodValueExerciseOfPrefundedWarrants" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="cyph_StockIssuedDuringPeriodSharesExerciseOfPrefundedWarrants" name="StockIssuedDuringPeriodSharesExerciseOfPrefundedWarrants" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="EquityIncentivePlan2022Member" id="cyph_EquityIncentivePlan2022Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OperatingLeaseAdditionalRightOfUseAsset" id="cyph_OperatingLeaseAdditionalRightOfUseAsset" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OperatingLeaseAdditionalLiability" id="cyph_OperatingLeaseAdditionalLiability" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SeriesXPreferredStockMember" id="cyph_SeriesXPreferredStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2020PreFundedWarrantsMember" id="cyph_March2020PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="March2020CoverageWarrantsMember" id="cyph_March2020CoverageWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="January2023CommonStockWarrantsMember" id="cyph_January2023CommonStockWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="January2023SeriesXPreferredStockWarrantsMember" id="cyph_January2023SeriesXPreferredStockWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="TemporaryStockConvertibleConversionRatio" id="cyph_TemporaryStockConvertibleConversionRatio" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="SummaryOfSignificantAccountingPoliciesTable" id="cyph_SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SignificantAccountingPoliciesLineItems" id="cyph_SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Warrants2019Member" id="cyph_Warrants2019Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Equityincentiveplan2016and2022Member" id="cyph_Equityincentiveplan2016and2022Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="September2021PreFundedWarrantsMember" id="cyph_September2021PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CommonStockTable" id="cyph_CommonStockTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CommonStockLineItems" id="cyph_CommonStockLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WeightedAverageNumberOfSharesOutstandingExerciseOfPreFundedWarrantsAndPennyWarrants" id="cyph_WeightedAverageNumberOfSharesOutstandingExerciseOfPreFundedWarrantsAndPennyWarrants" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="April2024PreFundedWarrantsMember" id="cyph_April2024PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ClassOfWarrantOrRightWarrantsExercised" id="cyph_ClassOfWarrantOrRightWarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="StockIssuedDuringPeriodSharesWarrantsExercised" id="cyph_StockIssuedDuringPeriodSharesWarrantsExercised" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="HealthInsurancePremiumReceivable" id="cyph_HealthInsurancePremiumReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AnnualFixedInterestRateOfInsurancePremium" id="cyph_AnnualFixedInterestRateOfInsurancePremium" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="PaymentOfInsurancePremium" id="cyph_PaymentOfInsurancePremium" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="OutstandingPrincipalOfLoanIncludingAccruedExpensesRelatedToInsurancePremium" id="cyph_OutstandingPrincipalOfLoanIncludingAccruedExpensesRelatedToInsurancePremium" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="RestructuringAndRelatedCostReductionInWorkforceNumberOfPhases" id="cyph_RestructuringAndRelatedCostReductionInWorkforceNumberOfPhases" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RestructuringAndRelatedCostsPolicyTextBlock" id="cyph_RestructuringAndRelatedCostsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LesseeOperatingLeaseMinimumNoticePeriod" id="cyph_LesseeOperatingLeaseMinimumNoticePeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="October2025PrivatePlacementMember" id="cyph_October2025PrivatePlacementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="October2025PreFundedWarrantsMember" id="cyph_October2025PreFundedWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WarrantsIssuedPricePerWarrant" id="cyph_WarrantsIssuedPricePerWarrant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="October2025CommonWarrantsMember" id="cyph_October2025CommonWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="MaximumNumberOfDirectorsOnBoard" id="cyph_MaximumNumberOfDirectorsOnBoard" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="OrganizationConsolidationAndPresentationOfFinancialStatementsTable" id="cyph_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NatureOfBusinessBasisOfPresentationAndLiquidityLineItem" id="cyph_NatureOfBusinessBasisOfPresentationAndLiquidityLineItem" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PlacementAgentExpense" id="cyph_PlacementAgentExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PlacementAgentExpensePaidInCash" id="cyph_PlacementAgentExpensePaidInCash" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PlacementAgentWarrantsMember" id="cyph_PlacementAgentWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ClassOfWarrantOrRightTransferOfWarrantsOrUnderlyingSharesRestrictionPeriod" id="cyph_ClassOfWarrantOrRightTransferOfWarrantsOrUnderlyingSharesRestrictionPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ClassOfWarrantOrRightAggregatePurchasePricePerUnitWithCommonShares" id="cyph_ClassOfWarrantOrRightAggregatePurchasePricePerUnitWithCommonShares" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ResearchAndDevelopmentIncentiveIncomeExpense" id="cyph_ResearchAndDevelopmentIncentiveIncomeExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AtMarketOfferingMember" id="cyph_AtMarketOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockSubscriptionReceivableFromIssuanceOfCommonStock" id="cyph_StockSubscriptionReceivableFromIssuanceOfCommonStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="CryptoAssetsPolicyPolicyTextBlock" id="cyph_CryptoAssetsPolicyPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SaleOfStockValueOfSharesIssuedOrIssuableInTransaction" id="cyph_SaleOfStockValueOfSharesIssuedOrIssuableInTransaction" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockSubscriptionReceivableTextBlock" id="cyph_StockSubscriptionReceivableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CantorFitzgeraldAndCoMember" id="cyph_CantorFitzgeraldAndCoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockSubscriptionReceivableAbstract" id="cyph_StockSubscriptionReceivableAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CryptoAssetAveragePurchasePricePerUnit" id="cyph_CryptoAssetAveragePurchasePricePerUnit" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CryptoAssetNumberOfUnitsPurchased" id="cyph_CryptoAssetNumberOfUnitsPurchased" type="xbrli:decimalItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SaleOfStockPercentageOfCommissionOnGrossProceeds" id="cyph_SaleOfStockPercentageOfCommissionOnGrossProceeds" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SaleOfStockTerminationPriorNoticeNumberOfBusinessDays" id="cyph_SaleOfStockTerminationPriorNoticeNumberOfBusinessDays" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SaleOfStockCommission" id="cyph_SaleOfStockCommission" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="AmortizationOfStockIssuanceCosts" id="cyph_AmortizationOfStockIssuanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ZcashOpenDevelopmentLabMember" id="cyph_ZcashOpenDevelopmentLabMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WinklevossCapitalMember" id="cyph_WinklevossCapitalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CryptoAssetHostContractFairValue" id="cyph_CryptoAssetHostContractFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ProceedsFromCollectionOfStockSubscriptionReceivable" id="cyph_ProceedsFromCollectionOfStockSubscriptionReceivable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="SaleOfStockConsiderationReceivedOnTransactionProceeds" id="cyph_SaleOfStockConsiderationReceivedOnTransactionProceeds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="OtherLongTermInvestmentsAbstract" id="cyph_OtherLongTermInvestmentsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OtherLongTermInvestmentsDisclosureTextBlock" id="cyph_OtherLongTermInvestmentsDisclosureTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="October2025CommonWarrantsInvestorsMember" id="cyph_October2025CommonWarrantsInvestorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="October2025CommonWarrantsPlacementAgentWarrantsMember" id="cyph_October2025CommonWarrantsPlacementAgentWarrantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
