@@ -41,13 +41,27 @@ jobs:
       - name: Setup toolchain
         uses: ./.github/actions/setup-node-pnpm
 
+      - name: Fetch the PR base for Android smoke selection
+        if: github.event_name == 'pull_request'
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: git fetch origin "$BASE_SHA" --depth=1 || echo "Base fetch failed; Android smoke selection will fail open."
+
+      - name: Select Android smoke tests
+        id: impact
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: node --experimental-strip-types scripts/device-lane-impact.ts replay-android android-helpers
+
       - name: Setup Android replay host
+        if: steps.impact.outputs.run != 'false'
         id: android-replay-host
         uses: ./.github/actions/setup-android-replay-host
         with:
           package-helpers: 'true'
 
       - name: Restore fixture APK
+        if: steps.impact.outputs.run != 'false'
         id: fixture-app
         uses: ./.github/actions/setup-fixture-app
         with:
@@ -56,12 +70,15 @@ jobs:
           wait-for-artifact-seconds: '1800'
 
       - name: Report fixture cache source
+        if: steps.impact.outputs.run != 'false'
         run: echo "Android fixture APK source=${{ steps.fixture-app.outputs.source }}"
 
       - name: Run Android emulator catalog coverage contract
+        if: steps.impact.outputs.run != 'false'
         run: node --experimental-strip-types scripts/node-test-tmpdir.ts --test test/integration/smoke-android-emulator-coverage.test.ts
 
       - name: Run Android smoke checks
+        if: steps.impact.outputs.run != 'false'
         uses: reactivecircus/android-emulator-runner@b530d96654c385303d652368551fb075bc2f0b6b # v2.35.0
         with:
           api-level: 36
@@ -79,7 +96,7 @@ jobs:
             node --experimental-strip-types src/bin.ts test test/integration/replays/android/emulator/01-settings.ad --retries 2 --report-junit test/artifacts/replays-android-smoke.junit.xml
 
       - name: Upload Android artifacts
-        if: always()
+        if: always() && steps.impact.outputs.run != 'false'
         uses: ./.github/actions/upload-agent-device-artifacts
         with:
           artifact-name: android-artifacts
 
@@ -56,15 +56,20 @@ jobs:
         shell: bash
         run: |
           git fetch origin "$BASE_SHA" --depth=1 || echo "Base fetch failed; Apple selection will fail open."
+      - name: Select iOS smoke tests
+        id: ios-impact
+        shell: bash
+        run: node --experimental-strip-types scripts/apple-ci-impact.ts smoke
+      - name: Select macOS smoke tests
+        id: macos-impact
+        shell: bash
+        run: node --experimental-strip-types scripts/apple-ci-impact.ts macos
       - name: Build the shared CLI
         id: build
+        if: steps.ios-impact.outputs.run != 'false' || steps.macos-impact.outputs.run != 'false'
         uses: ./.github/actions/run-gate
         with:
           gate: build
-      - name: Select iOS smoke tests
-        id: ios-impact
-        shell: bash
-        run: node --experimental-strip-types scripts/apple-ci-impact.ts smoke
       # The macOS clean-install proof may raise permission UI. Run the iOS focus proof first.
       - name: iOS smoke tests
         id: ios
@@ -101,7 +106,7 @@ jobs:
           RESULT_BUNDLE_PATH: ${{ github.workspace }}/.tmp/xctest-host/RunnerTests.xcresult
           RESULT_SUMMARY_PATH: ${{ github.workspace }}/.tmp/xctest-host/test-results-summary.json
           XCTEST_LANE: host
-        if: ${{ !cancelled() && steps.build.outcome == 'success' && steps.ios-cleanup.outcome == 'success' }}
+        if: ${{ !cancelled() && steps.build.outcome == 'success' && steps.ios-cleanup.outcome == 'success' && steps.macos-impact.outputs.run != 'false' }}
       - name: Diagnose the Apple host after a phase failure
         if: ${{ always() && (steps.ios.outcome == 'failure' || steps.macos.outcome == 'failure' || steps.ios-cleanup.outcome == 'failure') }}
         continue-on-error: true
@@ -119,11 +124,12 @@ jobs:
         shell: bash
         run: |
           pnpm clean:daemon
-      - name: Require both Apple phases to succeed
+      - name: Require the selected Apple phases to succeed
         if: always()
         env:
           IOS_SELECTED: ${{ steps.ios-impact.outputs.run }}
           IOS_OUTCOME: ${{ steps.ios.outcome }}
+          MACOS_SELECTED: ${{ steps.macos-impact.outputs.run }}
           MACOS_OUTCOME: ${{ steps.macos.outcome }}
           IOS_CLEANUP_OUTCOME: ${{ steps.ios-cleanup.outcome }}
           MACOS_CLEANUP_OUTCOME: ${{ steps.macos-cleanup.outcome }}
@@ -136,9 +142,18 @@ jobs:
           else
             test "$IOS_OUTCOME" = success
           fi
-          test "$MACOS_OUTCOME" = success
-          test "$IOS_CLEANUP_OUTCOME" = success
-          test "$MACOS_CLEANUP_OUTCOME" = success
+          if [ "$MACOS_SELECTED" = false ]; then
+            test "$MACOS_OUTCOME" = skipped
+          else
+            test "$MACOS_OUTCOME" = success
+          fi
+          if [ "$IOS_SELECTED" = false ] && [ "$MACOS_SELECTED" = false ]; then
+            test "$IOS_CLEANUP_OUTCOME" = skipped
+            test "$MACOS_CLEANUP_OUTCOME" = skipped
+          else
+            test "$IOS_CLEANUP_OUTCOME" = success
+            test "$MACOS_CLEANUP_OUTCOME" = success
+          fi
       - name: Upload Apple artifacts
         if: always()
         uses: ./.github/actions/upload-agent-device-artifacts
 
@@ -395,21 +395,35 @@ jobs:
         uses: ./.github/actions/run-gate
         with: { gate: fixture-cache }
 
+      - name: Fetch the PR base for web smoke selection
+        if: github.event_name == 'pull_request'
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: git fetch origin "$BASE_SHA" --depth=1 || echo "Base fetch failed; web smoke selection will fail open."
+
+      - name: Select web smoke tests
+        id: web-impact
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: node --experimental-strip-types scripts/device-lane-impact.ts web-smoke
+
       # Shares this job's ubuntu toolchain. AGENT_DEVICE_WEB_E2E is step-scoped
       # so it cannot leak into the node/provider suites above.
       - name: Run live web smoke
+        if: steps.web-impact.outputs.run != 'false'
         env:
           AGENT_DEVICE_WEB_E2E: '1'
         run: pnpm clean:daemon
 
       - name: Execute live web smoke
+        if: steps.web-impact.outputs.run != 'false'
         env:
           AGENT_DEVICE_WEB_E2E: '1'
         uses: ./.github/actions/run-gate
         with: { gate: web-smoke }
 
       - name: Upload web smoke artifacts
-        if: always()
+        if: always() && steps.web-impact.outputs.run != 'false'
         uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: web-smoke-artifacts
 
@@ -46,6 +46,21 @@ jobs:
       - name: Checkout
         uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
+      - name: Setup toolchain
+        uses: ./.github/actions/setup-node-pnpm
+
+      - name: Fetch the PR base for Linux smoke selection
+        if: github.event_name == 'pull_request'
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: git fetch origin "$BASE_SHA" --depth=1 || echo "Base fetch failed; Linux smoke selection will fail open."
+
+      - name: Select Linux smoke tests
+        id: impact
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: node --experimental-strip-types scripts/device-lane-impact.ts replay-linux linux-command-evidence
+
       # Unbounded, this step could not fail — it could only stall. On 2026-08-19 a slow mirror
       # held apt past the job's 30-minute budget on four main-branch runs and several unrelated
       # PRs, which reported as a red check on branches that never ran a line of project code.
@@ -54,6 +69,7 @@ jobs:
       # that drips bytes slowly enough to defeat the socket timeout. A healthy install takes
       # about a minute, so six is generous.
       - name: Install Linux desktop dependencies
+        if: steps.impact.outputs.run != 'false'
         timeout-minutes: 6
         run: |
           set -euo pipefail
@@ -77,10 +93,8 @@ jobs:
             gnome-calculator \
             wmctrl
 
-      - name: Setup toolchain
-        uses: ./.github/actions/setup-node-pnpm
-
       - name: Start Xvfb and D-Bus
+        if: steps.impact.outputs.run != 'false'
         run: |
           # Start virtual framebuffer (1280x1024, 24-bit color)
           Xvfb :99 -screen 0 1280x1024x24 &
@@ -93,6 +107,7 @@ jobs:
           echo "DBUS_SESSION_BUS_PID=$DBUS_SESSION_BUS_PID" >> "$GITHUB_ENV"
 
       - name: Start AT-SPI2 registry
+        if: steps.impact.outputs.run != 'false'
         run: |
           # The registry must start AFTER DBUS_SESSION_BUS_ADDRESS is available
           # (it was written to GITHUB_ENV in the previous step).
@@ -112,6 +127,7 @@ jobs:
           fi
 
       - name: Verify environment
+        if: steps.impact.outputs.run != 'false'
         run: |
           echo "=== Display ==="
           xdotool getdisplaygeometry
@@ -125,9 +141,11 @@ jobs:
           xdotool version
 
       - name: Run Linux replay smoke test
+        if: steps.impact.outputs.run != 'false'
         run: pnpm clean:daemon
 
       - name: Execute Linux replay smoke test
+        if: steps.impact.outputs.run != 'false'
         uses: ./.github/actions/run-gate
         with:
           gate: replay-linux
@@ -138,15 +156,17 @@ jobs:
             test/artifacts/replays-linux.junit.xml
 
       - name: Reset daemon before Linux command evidence
+        if: steps.impact.outputs.run != 'false'
         run: pnpm clean:daemon
 
       - name: Execute Linux command evidence
+        if: steps.impact.outputs.run != 'false'
         uses: ./.github/actions/run-gate
         with:
           gate: linux-command-evidence
 
       - name: Upload Linux artifacts
-        if: always()
+        if: always() && steps.impact.outputs.run != 'false'
         uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: linux-artifacts
 
@@ -30,17 +30,30 @@ static AccessibilityNodeInfo root(AccessibilityWindowInfo window) {
     return window.getRoot();
   }
 
+  interface Read<T> {
+    T read();
+  }
+
   /**
    * The child, or null when it is gone. When the child's window closes during the read, the
    * framework can throw a NullPointerException from its result integrity check instead of answering
    * null (seen on API 35 while an alert dialog closed), so that throw means the same as null.
+   *
+   * <p>A null {@code node} is a programmer error, but the same catch hides its NullPointerException
+   * as a gone child.
    */
   static AccessibilityNodeInfo child(AccessibilityNodeInfo node, int index) {
+    return nullIfGone(
+        () ->
+            Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU
+                ? node.getChild(index, PREFETCH_STRATEGY)
+                : node.getChild(index));
+  }
+
+  /** Runs a framework read that answers null for a vanished node and can throw instead. */
+  static <T> T nullIfGone(Read<T> read) {
     try {
-      if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
-        return node.getChild(index, PREFETCH_STRATEGY);
-      }
-      return node.getChild(index);
+      return read.read();
     } catch (NullPointerException vanished) {
       return null;
     }
 
@@ -14,6 +14,7 @@ static void run() throws Exception {
     releasesUnreadResultsAfterFailure();
     waitsForReadersBeforeReleasingTheParent();
     preservesInterruptionDuringCleanup();
+    readsAChildThatVanishedMidReadAsGone();
   }
 
   private static void queuesConcurrentReadsAndPreservesOrder() throws Exception {
@@ -134,6 +135,41 @@ private static void preservesInterruptionDuringCleanup() {
     }
   }
 
+  private static void readsAChildThatVanishedMidReadAsGone() {
+    List<Integer> recycled = new ArrayList<>();
+    try (AccessibilityReadBatch<Integer> batch =
+        new AccessibilityReadBatch<>(
+            0, 3,
+            index ->
+                AccessibilityNodeReads.nullIfGone(
+                    () -> {
+                      if (index == 1) {
+                        throw new NullPointerException("window closed");
+                      }
+                      if (index == 2) {
+                        throw new IllegalStateException("not a vanished child");
+                      }
+                      return index;
+                    }),
+            recycled::add)) {
+      if (batch.get(0) != 0) {
+        throw new AssertionError("Expected the first child");
+      }
+      if (batch.get(1) != null) {
+        throw new AssertionError("A child that vanished mid-read must read as gone");
+      }
+      try {
+        batch.get(2);
+        throw new AssertionError("Other read failures must propagate");
+      } catch (IllegalStateException expected) {
+        // Only the vanished-window throw means a gone child.
+      }
+    }
+    if (!recycled.equals(Arrays.asList(0))) {
+      throw new AssertionError("Only the present child must be released: " + recycled);
+    }
+  }
+
   private static void await(CountDownLatch latch) {
     try {
       if (!latch.await(2, TimeUnit.SECONDS)) {
 
@@ -129,6 +129,26 @@ extension RunnerTests {
     else {
       return .failure(RunnerAppScreenCaptureFailure(resolution))
     }
+    return capturedScreen(captureScreen, displayID: displayID)
+  }
+
+  /// Samples the same sole-screen route that synthesized gestures use when the app tree refuses
+  /// its window. This route cannot name a screen on an iPad or a multi-screen iPhone.
+  func captureSoleAppScreen() -> Result<CapturedAppScreen, RunnerAppScreenCaptureFailure> {
+    var screen: AnyObject?
+    var displayID: UInt = 0
+    guard RunnerResolveSoleScreen(&screen, &displayID) == nil,
+      let captureScreen = screen as? XCUIScreen
+    else {
+      return .failure(.unresolvedScreen)
+    }
+    return Self.capturedScreen(captureScreen, displayID: displayID)
+  }
+
+  private static func capturedScreen(
+    _ captureScreen: XCUIScreen,
+    displayID: UInt
+  ) -> Result<CapturedAppScreen, RunnerAppScreenCaptureFailure> {
     let image = captureScreen.screenshot().image
     guard let upright = runnerUprightCaptureImage(image) else {
       return .failure(.unrenderableImage)
 
@@ -132,7 +132,7 @@ extension RunnerTests {
     privateAXAcceptedDepthBundleId = bundleId
     privateAXAcceptedDepthProcessIdentifier = processIdentifier
     privateAXAcceptedDepth = depth
-    privateAXAcceptedDepthUntil = Date().addingTimeInterval(snapshotXCTestChannelPenaltyDuration)
+    privateAXAcceptedDepthUntil = Date().addingTimeInterval(SnapshotXCTestChannelPenalty.duration)
     privateAXAcceptedDepthLock.unlock()
     NSLog("AGENT_DEVICE_RUNNER_PRIVATE_AX_DEPTH_REMEMBERED depth=%ld bundle=%@", depth, bundleId ?? "")
   }
Original file line number	Diff line number	Diff line change
`@@ -132,7 +132,7 @@ extension RunnerTests {`
`132`	`132`	`privateAXAcceptedDepthBundleId = bundleId`
`133`	`133`	`privateAXAcceptedDepthProcessIdentifier = processIdentifier`
`134`	`134`	`privateAXAcceptedDepth = depth`
`135`		`- privateAXAcceptedDepthUntil = Date().addingTimeInterval(snapshotXCTestChannelPenaltyDuration)`
	`135`	`+ privateAXAcceptedDepthUntil = Date().addingTimeInterval(SnapshotXCTestChannelPenalty.duration)`
`136`	`136`	`privateAXAcceptedDepthLock.unlock()`
`137`	`137`	`NSLog("AGENT_DEVICE_RUNNER_PRIVATE_AX_DEPTH_REMEMBERED depth=%ld bundle=%@", depth, bundleId ?? "")`
`138`	`138`	`}`