diff --git a/tools/pipelines/templates/include-conditionally-run-stress-tests.yml b/tools/pipelines/templates/include-conditionally-run-stress-tests.yml
index 22d45092cce7..b2c446a0f5d7 100644
--- a/tools/pipelines/templates/include-conditionally-run-stress-tests.yml
+++ b/tools/pipelines/templates/include-conditionally-run-stress-tests.yml
@@ -30,6 +30,14 @@ parameters:
 - name: artifactBuildId
   type: string
 
+# A valid git ref to use for the microsoft/FluidFramework repository checkout (e.g. refs/heads/main, a commit SHA, tag, etc)
+# Pipelines that are triggered on completion of the "Build - client packages" pipeline should generally use
+# the same source commit as what was used for "Build - client packages". This is typically available via
+# `$(resources.pipeline.client.sourceCommit)` (where "client" is actually the name of the resource declared
+# in the current pipeline's root yaml file)
+- name: fluidFrameworkSourceVersion
+  type: string
+
 stages:
   - stage: CheckAffectedPaths
     displayName: Determine changed packages
@@ -73,6 +81,7 @@ stages:
         condition: eq(dependencies.CheckAffectedPaths.outputs['Job.Check${{ replace(package.testFileTarName, '-', '') }}.AffectedFilesModified'],'true')
         poolBuild: ${{ parameters.pool }}
         artifactBuildId: ${{ parameters.artifactBuildId }}
+        fluidFrameworkSourceVersion: ${{ parameters.fluidFrameworkSourceVersion }}
         testPackage: ${{ package.name }}
         timeoutInMinutes: 120
         testFileTarName: ${{ package.testFileTarName }}
diff --git a/tools/pipelines/templates/include-install-pnpm.yml b/tools/pipelines/templates/include-install-pnpm.yml
index 23f3509f4af4..6207eb48abe4 100644
--- a/tools/pipelines/templates/include-install-pnpm.yml
+++ b/tools/pipelines/templates/include-install-pnpm.yml
@@ -31,6 +31,17 @@ parameters:
   type: string
   default: $(ado-feeds-primary-registry)
 
+# An optional extra segment appended to the pnpm store cache key (separated by |).
+# Note that Azure pipelines interpret unquoted cache keys as files rather than literal strings. E.g. the following specification:
+#
+# additionalCacheKey: 'foo | "bar"'
+#
+# will use the hashed contents of the file "foo" (hashing nothing if that file does not exist) as well as the string "bar".
+# Use this parameter if the set of dependencies to be installed may be be better distinguished using files other than the root pnpm-lock.
+- name: additionalCacheKey
+  type: string
+  default: ''
+
 steps:
 - ${{ if eq(parameters.enableCache, true) }}:
   - task: Cache@2
@@ -43,7 +54,10 @@ steps:
     inputs:
       # Caches are already scoped to individual pipelines, so no need to include the release group name or tag
       # in the cache key
-      key: '"pnpm-store" | "$(Agent.OS)" | $(Pipeline.Workspace)/${{ parameters.buildDirectory }}/pnpm-lock.yaml'
+      ${{ if ne(parameters.additionalCacheKey, '') }}:
+        key: '"pnpm-store" | "$(Agent.OS)" | $(Pipeline.Workspace)/${{ parameters.buildDirectory }}/pnpm-lock.yaml | ${{ parameters.additionalCacheKey }}'
+      ${{ else }}:
+        key: '"pnpm-store" | "$(Agent.OS)" | $(Pipeline.Workspace)/${{ parameters.buildDirectory }}/pnpm-lock.yaml'
       path: ${{ parameters.pnpmStorePath }}
       restoreKeys: |
         "pnpm-store" | "$(Agent.OS)"
diff --git a/tools/pipelines/templates/include-test-real-service.yml b/tools/pipelines/templates/include-test-real-service.yml
index 1faeeceb0c7f..6ebd3b694398 100644
--- a/tools/pipelines/templates/include-test-real-service.yml
+++ b/tools/pipelines/templates/include-test-real-service.yml
@@ -71,6 +71,15 @@ parameters:
 - name: artifactBuildId
   type: string
 
+# A valid git ref to use for the microsoft/FluidFramework repository checkout (e.g. refs/heads/main, a commit SHA, tag, etc)
+# Pipelines that are triggered on completion of the "Build - client packages" pipeline should generally use
+# the same source commit as what was used for "Build - client packages". This is typically available via
+# `$(resources.pipeline.client.sourceCommit)` (where "client" is actually the name of the resource declared
+# in the current pipeline's root yaml file)
+- name: fluidFrameworkSourceVersion
+  type: string
+  default: $(Build.SourceVersion)
+
 # Name of the Secure File that contains the self-signed cert for the R11s deployment.
 # If not blank, the pipeline will try to install it to the local cert store.
 - name: r11sSelfSignedCertSecureFile
@@ -88,11 +97,6 @@ parameters:
   type: boolean
   default: false
 
-# If true, the versions of our packages installed for compat testing will be cached.
-- name: cacheCompatVersionsInstalls
-  type: boolean
-  default: false
-
 # If tests need to run against an ODSP tenant, specify the type of tenant here. Steps will be injected to lease one for the duration of the test.
 - name: odspTenantType
   type: string
@@ -174,6 +178,22 @@ stages:
           path: $(FFPipelineHostDirectory)
           clean: true
 
+        # ADO doesn't support checking out refs that are determined at pipeline queue time as ours likely would be
+        # (where the ref is a function of one of the pipeline resource inputs). See docs here:
+        # https://learn.microsoft.com/en-us/azure/devops/pipelines/repos/multi-repo-checkout?view=azure-devops#checking-out-a-specific-ref
+        # To work around this, we get to the right revision in a follow-up step.
+        - checkout: self
+          path: $(FluidFrameworkDirectory)
+          clean: true
+
+        - bash: |
+            git fetch --depth=1 origin $FF_SOURCE_VERSION
+            git checkout $FF_SOURCE_VERSION
+          workingDirectory: $(Pipeline.Workspace)/$(FluidFrameworkDirectory)
+          displayName: Switch FluidFramework checkout to artifact source version
+          env:
+            FF_SOURCE_VERSION: ${{ parameters.fluidFrameworkSourceVersion }}
+
         # Install self-signed cert for R11s deployment in local cert store
         - ${{ if ne(parameters.r11sSelfSignedCertSecureFile, '') }}:
           - task: DownloadSecureFile@1
@@ -231,15 +251,15 @@ stages:
         - template: /tools/pipelines/templates/include-install-pnpm.yml@self
           parameters:
             buildDirectory: $(FFPipelineHostDirectory)
+            # The compat-workspaces lockfile is committed to the FluidFramework repo and changes
+            # whenever legacy package versions are added or removed. Including it in the pnpm store
+            # cache key ensures a cache miss whenever the set of compat packages changes.
+            additionalCacheKey: '$(Pipeline.Workspace)/$(FluidFrameworkDirectory)/packages/test/test-version-utils/compat-workspaces/full/pnpm-lock.yaml'
 
         - template: /tools/pipelines/templates/include-setup-npmrc-for-download.yml@self
 
         # Set up Docker environment if running against docker
         - ${{ if eq(parameters.runAgainstDocker, true) }}:
-          # Checks out FluidFramework repo
-          - checkout: self
-            path: $(FluidFrameworkDirectory)
-            clean: true
           - task: Docker@2
             displayName: 'Login to container registry'
             inputs:
@@ -371,43 +391,6 @@ stages:
               sourcePackageLocation: $(Pipeline.Workspace)/$(FFPipelineHostDirectory)/node_modules/${{ parameters.testPackage }}
               destPackageLocation: $(Pipeline.Workspace)/$(FFPipelineHostDirectory)
 
-        - ${{ if eq(parameters.cacheCompatVersionsInstalls, true) }}:
-          - task: Bash@3
-            displayName: Compute compat versions install location and version
-            inputs:
-              targetType: 'inline'
-              workingDirectory: $(Pipeline.Workspace)/$(FFPipelineHostDirectory)/node_modules/@fluid-private/test-end-to-end-tests
-              # Using import.meta.resolve to compute this is more resilient to different install tree types.
-              # Also note that test-version-utils is esm-only, so cannot be loaded with require.
-              script: |
-                set -eu -o pipefail
-                node --input-type=module -e "
-                  import { createRequire } from 'module';
-                  const require = createRequire(import.meta.url);
-                  const path = require('path');
-                  const versionUtilsIndexUrl = await import.meta.resolve('@fluid-private/test-version-utils');
-                  const basePath = new URL(versionUtilsIndexUrl.replace('/lib/index.js', '')).pathname;
-                  const legacyModulesPath = path.join(basePath, 'node_modules', '.legacy');
-                  console.log('Resolved @fluid-private/test-version-utils legacy modules to ' + legacyModulesPath);
-                  console.log('##vso[task.setvariable variable=compatVersionInstallsPath]' + legacyModulesPath);
-                  const packageJsonPath = path.join(basePath, 'package.json');
-                  const packageJson = require(packageJsonPath);
-                  const packageVersion = packageJson.version;
-                  const [major, minor] = packageVersion.split('.');
-                  const cacheKey = 'major:' + major + ',minor:' + minor;
-                  console.log('Computed compat version cache key: ' + cacheKey);
-                  console.log('##vso[task.setvariable variable=compatVersionCacheKey;]'+ cacheKey);
-                "
-
-          - task: Cache@2
-            displayName: Cache compat versions install location
-            timeoutInMinutes: 3
-            continueOnError: true
-            inputs:
-              # Increment the number on the cache-bust key (no special semantics) to force a new cache key.
-              key: '"compat-version-installs" | "cache-bust-1" | "$(Agent.OS)" | "${{ parameters.testCommand }}" | "${{ variant.name }}" | "$(compatVersionCacheKey)"'
-              path: $(compatVersionInstallsPath)
-
         # Only check out tenants from the tenant pool if we are running tests against ODSP
         - ${{ if ne(parameters.odspTenantType, 'none') }}:
           # Retrieve a tenant from the tenant pool
@@ -429,6 +412,7 @@ stages:
               SYSTEM_ACCESSTOKEN: $(System.AccessToken)
             inputs:
               targetType: 'inline'
+              workingDirectory: $(Pipeline.Workspace)/$(FFPipelineHostDirectory)
               script: |
                 set -eu -o pipefail
 
@@ -528,6 +512,7 @@ stages:
               SYSTEM_ACCESSTOKEN: $(System.AccessToken)
             inputs:
               targetType: 'inline'
+              workingDirectory: $(Pipeline.Workspace)/$(FFPipelineHostDirectory)
               script: |
                 set -eu -o pipefail
                 pnpm exec trips-cleanup --odspEndpoint=${{ parameters.odspTenantType }} --useFic
diff --git a/tools/pipelines/test-dds-stress.yml b/tools/pipelines/test-dds-stress.yml
index ff98abacb2cd..af6dd7f2a5d0 100644
--- a/tools/pipelines/test-dds-stress.yml
+++ b/tools/pipelines/test-dds-stress.yml
@@ -43,6 +43,7 @@ stages:
   - template: /tools/pipelines/templates/include-conditionally-run-stress-tests.yml@self
     parameters:
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       packages:
         - name: "@fluidframework/sequence"
           affectedPaths:
diff --git a/tools/pipelines/test-real-service-stress.yml b/tools/pipelines/test-real-service-stress.yml
index 89e4844c3299..20ca4f0b8fd6 100644
--- a/tools/pipelines/test-real-service-stress.yml
+++ b/tools/pipelines/test-real-service-stress.yml
@@ -47,6 +47,7 @@ stages:
       poolBuild: Large-eastus2
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       timeoutInMinutes: 120
       testCommand: start:odsp
       skipTestResultPublishing: true
@@ -64,6 +65,7 @@ stages:
       poolBuild: Large-eastus2
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       timeoutInMinutes: 120
       testCommand: start:odspdf
       skipTestResultPublishing: true
@@ -80,6 +82,7 @@ stages:
       poolBuild: Large-eastus2
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       timeoutInMinutes: 120
       testCommand: start:t9s
       skipTestResultPublishing: true
@@ -99,6 +102,7 @@ stages:
       poolBuild: Large-eastus2
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       timeoutInMinutes: 120
       testCommand: start:frs
       lockBehavior: sequential
@@ -119,6 +123,7 @@ stages:
       poolBuild: Large-eastus2
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       timeoutInMinutes: 120
       testCommand: start:frs:canary
       lockBehavior: sequential
diff --git a/tools/pipelines/test-real-service.yml b/tools/pipelines/test-real-service.yml
index 4c0575c802e1..fda39698becd 100644
--- a/tools/pipelines/test-real-service.yml
+++ b/tools/pipelines/test-real-service.yml
@@ -58,8 +58,9 @@ stages:
       poolBuild: Large-eastus2 # Need Large pool for full-compat matrix
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       testCommand: test:realsvc:local:report:full
-      cacheCompatVersionsInstalls: true
+
       uploadTestPassRateTelemetry: true
       pipelineIdentifierForTelemetry: ${{ variables.pipelineIdentifierForTelemetry }}
       env:
@@ -74,8 +75,9 @@ stages:
       poolBuild: Large-eastus2 # Need Large pool for full-compat matrix
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       testCommand: test:realsvc:tinylicious:report:full
-      cacheCompatVersionsInstalls: true
+
       # TODO: AB#8968 tracks figuring out the root cause of the extended delay, and restoring this timeout to 90m or less
       timeoutInMinutes: 120
       uploadTestPassRateTelemetry: true
@@ -95,6 +97,7 @@ stages:
       poolBuild: Large-eastus2 # Need Large pool for full-compat matrix
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       continueOnError: true
       timeoutInMinutes: 360
       testCommand: test:realsvc:r11s:docker
@@ -109,7 +112,7 @@ stages:
           flags: --compatVersion=OCV
         - name: Cross-Client
           flags: --compatVersion=CROSS_CLIENT
-      cacheCompatVersionsInstalls: true
+
       uploadTestPassRateTelemetry: true
       pipelineIdentifierForTelemetry: ${{ variables.pipelineIdentifierForTelemetry }}
 
@@ -134,6 +137,7 @@ stages:
       poolBuild: Small-eastus2
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       timeoutInMinutes: 360
       continueOnError: true
       testCommand: test:realsvc:frs:report
@@ -150,7 +154,7 @@ stages:
           flags: --compatVersion=OCV
         - name: Cross-Client
           flags: --compatVersion=CROSS_CLIENT
-      cacheCompatVersionsInstalls: true
+
       uploadTestPassRateTelemetry: true
       pipelineIdentifierForTelemetry: ${{ variables.pipelineIdentifierForTelemetry }}
       env:
@@ -167,6 +171,7 @@ stages:
       poolBuild: Small-eastus2
       testPackage: ${{ variables.testPackage }}
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       timeoutInMinutes: 360
       continueOnError: true
       testCommand: test:realsvc:odsp:report
@@ -182,7 +187,7 @@ stages:
         # Tests N-2 to LTS+3 back compat for loader + driver
         - name: N-2ToLTS+1-back-compat
           flags: --compatVersion=V2_INT_3 --tenantIndex=3
-      cacheCompatVersionsInstalls: true
+
       uploadTestPassRateTelemetry: true
       pipelineIdentifierForTelemetry: ${{ variables.pipelineIdentifierForTelemetry }}
       env:
diff --git a/tools/pipelines/test-service-clients.yml b/tools/pipelines/test-service-clients.yml
index 9a7aec43aa58..56dfea9b634b 100644
--- a/tools/pipelines/test-service-clients.yml
+++ b/tools/pipelines/test-service-clients.yml
@@ -52,6 +52,7 @@ stages:
       testPackage: ${{ variables.testPackage }}
       testCommand: test:realsvc:azure
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       pipelineIdentifierForTelemetry: ${{ variables.pipelineIdentifierForTelemetry }}
       env:
         FLUID_TEST_SCALE: true # run longer duration tests
@@ -69,6 +70,7 @@ stages:
       testPackage: ${{ variables.testPackage }}
       testCommand: test:realsvc:tinylicious
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       pipelineIdentifierForTelemetry: ${{ variables.pipelineIdentifierForTelemetry }}
       env:
         FLUID_TEST_SCALE: true # run longer duration tests
@@ -88,6 +90,7 @@ stages:
       testPackage: ${{ variables.testOdspPackage }}
       testCommand: test:realsvc:odsp
       artifactBuildId: $(resources.pipeline.client.runID)
+      fluidFrameworkSourceVersion: $(resources.pipeline.client.sourceCommit)
       pipelineIdentifierForTelemetry: ${{ variables.pipelineIdentifierForTelemetry }}
       env:
         FLUID_TEST_SCALE: true # run longer duration tests