diff --git a/.github/runs-on.yml b/.github/runs-on.yml
new file mode 100644
index 00000000000..0965a316ff6
--- /dev/null
+++ b/.github/runs-on.yml
@@ -0,0 +1,17 @@
+runners:
+  linux-x64-builder:
+    family: ["c8i.2xlarge"]
+    spot: false
+    image: ubuntu24-full-x64
+    extras: s3-cache
+  linux-arm64-builder:
+    family: ["c8g.2xlarge"]
+    spot: false
+    image: ubuntu24-full-arm64
+    extras: s3-cache
+  linux-x64-tester:
+    family: ["m8i.2xlarge"]
+    spot: false
+    image: ubuntu24-full-x64
+    extras: s3-cache
+    volume: 60gb
diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index d64efb605fd..f5858c8506c 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -39,29 +39,31 @@ jobs:
     name: Release ${{ matrix.arch }}
     needs: changes
     if: always() && !cancelled() && (needs.changes.outputs.should_build == 'true' || needs.changes.result == 'skipped')
-    runs-on: ${{ matrix.os }}
+    runs-on: ${{ matrix.runs_on }}
     timeout-minutes: 120
 
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-24.04-arm, ubuntu-22.04]
         include:
-          - os: ubuntu-24.04-arm
+          - arch: linux_gcc_arm64
+            runs_on: runs-on=${{ github.run_id }}/family=c8g.2xlarge/spot=false/image=ubuntu24-full-arm64/extras=s3-cache
             package: QGroundControl-aarch64
             host: linux_arm64
-            arch: linux_gcc_arm64
 
-          - os: ubuntu-22.04
+          - arch: linux_gcc_64
+            runs_on: runs-on=${{ github.run_id }}/family=c8i.2xlarge/spot=false/image=ubuntu24-full-x64/extras=s3-cache
             package: QGroundControl-x86_64
             host: linux
-            arch: linux_gcc_64
 
     defaults:
       run:
         shell: bash
 
     steps:
+      - name: Enable RunsOn magic cache
+        uses: runs-on/action@v2
+
       - name: Harden Runner
         if: runner.arch != 'ARM64'
         uses: step-security/harden-runner@v2
@@ -123,14 +125,14 @@ jobs:
           binary-path: ${{ runner.temp }}/build/Release/QGroundControl
 
       - name: Analyze binary size
-        if: matrix.os == 'ubuntu-22.04'
+        if: matrix.arch == 'linux_gcc_64'
         uses: ./.github/actions/size-analysis
         with:
           binary-path: ${{ runner.temp }}/build/Release/QGroundControl
           output-file: ${{ runner.temp }}/build/metrics.json
 
       - name: Upload metrics artifact
-        if: matrix.os == 'ubuntu-22.04'
+        if: matrix.arch == 'linux_gcc_64'
         uses: actions/upload-artifact@v7
         with:
           name: size-metrics
@@ -185,7 +187,11 @@ jobs:
     name: ${{ matrix.job_name }}
     needs: [changes, debug-matrix]
     if: ${{ !cancelled() && (needs.changes.outputs.should_build == 'true' || needs.changes.result == 'skipped') }}
-    runs-on: ubuntu-22.04
+    # 60GB volume so the Debug build + Qt SDK + caches + Integration test
+    # artifacts fit comfortably; the 40GB default left only ~1-2GB headroom
+    # at peak and killed the runner agent before any diagnostic step could
+    # run.
+    runs-on: runs-on=${{ github.run_id }}/family=m8i.2xlarge/spot=false/image=ubuntu24-full-x64/extras=s3-cache/volume=60gb
     timeout-minutes: ${{ matrix.timeout_minutes }}
 
     strategy:
@@ -198,6 +204,9 @@ jobs:
         shell: bash
 
     steps:
+      - name: Enable RunsOn magic cache
+        uses: runs-on/action@v2
+
       - name: Harden Runner
         uses: step-security/harden-runner@v2
         with:
@@ -240,8 +249,29 @@ jobs:
           build-dir: ${{ runner.temp }}/build
           build-type: Debug
 
-      - name: Run Unit Tests
-        id: tests
+      # Split test execution by label: Unit tests parallelize cleanly (no
+      # MockLink/Vehicle shared state), Integration tests share LinkManager
+      # singletons and per-test RESOURCE_LOCK so they serialize naturally on
+      # one CTest invocation. Run them in two passes so the Unit pass can use
+      # all cores while the Integration pass stays correct.
+      - name: Run Unit Tests (parallel)
+        id: unit_tests
+        uses: ./.github/actions/run-unit-tests
+        env:
+          ASAN_OPTIONS: ${{ matrix.mode == 'sanitizers' && 'detect_leaks=1:halt_on_error=1:check_initialization_order=1' || '' }}
+          LSAN_OPTIONS: ${{ matrix.mode == 'sanitizers' && format('suppressions={0}/build/asan_suppressions.txt', runner.temp) || '' }}
+          UBSAN_OPTIONS: ${{ matrix.mode == 'sanitizers' && format('print_stacktrace=1:halt_on_error=1:suppressions={0}/build/ubsan_suppressions.txt', runner.temp) || '' }}
+        with:
+          build-dir: ${{ runner.temp }}/build
+          junit-output: junit-results-linux-${{ matrix.mode }}-unit.xml
+          ctest-output: test-output-linux-${{ matrix.mode }}-unit.txt
+          include-labels: 'Unit'
+          exclude-labels: ${{ matrix.exclude_labels }}
+          parallel: auto
+
+      - name: Run Integration Tests (serial)
+        id: integration_tests
+        if: always() && !cancelled() && steps.unit_tests.conclusion != 'cancelled'
         uses: ./.github/actions/run-unit-tests
         env:
           ASAN_OPTIONS: ${{ matrix.mode == 'sanitizers' && 'detect_leaks=1:halt_on_error=1:check_initialization_order=1' || '' }}
@@ -249,44 +279,65 @@ jobs:
           UBSAN_OPTIONS: ${{ matrix.mode == 'sanitizers' && format('print_stacktrace=1:halt_on_error=1:suppressions={0}/build/ubsan_suppressions.txt', runner.temp) || '' }}
         with:
           build-dir: ${{ runner.temp }}/build
-          junit-output: junit-results-linux-${{ matrix.mode }}.xml
-          ctest-output: test-output-linux-${{ matrix.mode }}.txt
-          include-labels: 'Unit|Integration'
+          junit-output: junit-results-linux-${{ matrix.mode }}-integration.xml
+          ctest-output: test-output-linux-${{ matrix.mode }}-integration.txt
+          include-labels: 'Integration'
           exclude-labels: ${{ matrix.exclude_labels }}
-          # Coverage requires serial execution (gcov writes race); sanitizers don't.
-          parallel: ${{ matrix.mode == 'coverage' && '1' || 'auto' }}
+          parallel: '1'
 
-      - name: Analyze Unit Test Durations
-        if: always() && !cancelled() && steps.tests.conclusion != 'skipped'
+      - name: Analyze Unit Test Durations (unit)
+        if: always() && !cancelled() && steps.unit_tests.conclusion != 'skipped'
         uses: ./.github/actions/test-duration-report
         with:
-          junit-path: ${{ runner.temp }}/build/junit-results-linux-${{ matrix.mode }}.xml
-          report-json-path: ${{ runner.temp }}/build/test-duration-linux-${{ matrix.mode }}.json
+          junit-path: ${{ runner.temp }}/build/junit-results-linux-${{ matrix.mode }}-unit.xml
+          report-json-path: ${{ runner.temp }}/build/test-duration-linux-${{ matrix.mode }}-unit.json
           top-n: '20'
           slow-threshold-seconds: '60'
 
-      - name: Report Test Results
-        if: always() && !cancelled() && steps.tests.conclusion != 'skipped'
+      - name: Analyze Unit Test Durations (integration)
+        if: always() && !cancelled() && steps.integration_tests.conclusion != 'skipped'
+        uses: ./.github/actions/test-duration-report
+        with:
+          junit-path: ${{ runner.temp }}/build/junit-results-linux-${{ matrix.mode }}-integration.xml
+          report-json-path: ${{ runner.temp }}/build/test-duration-linux-${{ matrix.mode }}-integration.json
+          top-n: '20'
+          slow-threshold-seconds: '60'
+
+      - name: Report Test Results (unit)
+        if: always() && !cancelled() && steps.unit_tests.conclusion != 'skipped'
         uses: ./.github/actions/test-report
         with:
           name: Unit Tests (${{ matrix.mode }})
           build-dir: ${{ runner.temp }}/build
-          junit-file: junit-results-linux-${{ matrix.mode }}.xml
-          output-file: test-output-linux-${{ matrix.mode }}.txt
-          artifact-name: test-results-linux-${{ matrix.mode }}
+          junit-file: junit-results-linux-${{ matrix.mode }}-unit.xml
+          output-file: test-output-linux-${{ matrix.mode }}-unit.txt
+          artifact-name: test-results-linux-${{ matrix.mode }}-unit
+          retention-days: 7
+          trunk-org-slug: ${{ vars.TRUNK_ORG_SLUG }}
+          trunk-token: ${{ secrets.TRUNK_TOKEN }}
+
+      - name: Report Test Results (integration)
+        if: always() && !cancelled() && steps.integration_tests.conclusion != 'skipped'
+        uses: ./.github/actions/test-report
+        with:
+          name: Integration Tests (${{ matrix.mode }})
+          build-dir: ${{ runner.temp }}/build
+          junit-file: junit-results-linux-${{ matrix.mode }}-integration.xml
+          output-file: test-output-linux-${{ matrix.mode }}-integration.txt
+          artifact-name: test-results-linux-${{ matrix.mode }}-integration
           retention-days: 7
           trunk-org-slug: ${{ vars.TRUNK_ORG_SLUG }}
           trunk-token: ${{ secrets.TRUNK_TOKEN }}
 
       - name: Upload Test Artifacts
-        if: always() && !cancelled() && steps.tests.conclusion != 'skipped'
+        if: always() && !cancelled() && (steps.unit_tests.conclusion != 'skipped' || steps.integration_tests.conclusion != 'skipped')
         uses: actions/upload-artifact@v7
         with:
           name: test-artifacts-linux-${{ matrix.mode }}
           path: |
-            ${{ runner.temp }}/build/test-output-linux-${{ matrix.mode }}.txt
-            ${{ runner.temp }}/build/junit-results-linux-${{ matrix.mode }}.xml
-            ${{ runner.temp }}/build/test-duration-linux-${{ matrix.mode }}.json
+            ${{ runner.temp }}/build/test-output-linux-${{ matrix.mode }}-*.txt
+            ${{ runner.temp }}/build/junit-results-linux-${{ matrix.mode }}-*.xml
+            ${{ runner.temp }}/build/test-duration-linux-${{ matrix.mode }}-*.json
           retention-days: 7
 
       - name: Verify coverage data files exist
diff --git a/src/Utilities/Platform/QGCKeychain.cc b/src/Utilities/Platform/QGCKeychain.cc
index 343d10cee06..b8eb0841b0a 100644
--- a/src/Utilities/Platform/QGCKeychain.cc
+++ b/src/Utilities/Platform/QGCKeychain.cc
@@ -90,14 +90,22 @@ bool indicatesMissingBackend(QKeychain::Error err)
     return err == QKeychain::NoBackendAvailable || err == QKeychain::AccessDenied;
 }
 
-// Linux libsecret backend reports DBus ServiceUnknown as OtherError — recognize it as "no backend".
+// Linux libsecret backend reports a few "no Secret Service reachable" conditions
+// as QKeychain::OtherError. Recognize the known patterns so we transparently fall
+// back to QSettings instead of failing the call.
 bool isMissingSecretService(QKeychain::Error err, const QString& errorString)
 {
     if (err != QKeychain::OtherError) {
         return false;
     }
-    return errorString.contains(QLatin1String("org.freedesktop.secrets")) ||
-           errorString.contains(QLatin1String("ServiceUnknown"));
+    // libsecret can't reach the Secret Service over D-Bus.
+    if (errorString.contains(QLatin1String("org.freedesktop.secrets")) ||
+        errorString.contains(QLatin1String("ServiceUnknown"))) {
+        return true;
+    }
+    // No session bus to talk to (headless CI without dbus-launch / gnome-keyring).
+    return errorString.contains(QLatin1String("autolaunch D-Bus")) ||
+           errorString.contains(QLatin1String("DBUS_SESSION_BUS_ADDRESS"));
 }
 
 }  // namespace