diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index 09e5964a3..a6658fba2 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -4,8 +4,9 @@ name: CodeQL
 on:
   push:
     branches: [main]
+  # Every pull request, whatever its base, plus each merge queue group.
   pull_request:
-    branches: [main]
+  merge_group:
   schedule:
     - cron: "23 5 * * 1"
 
diff --git a/.github/workflows/dependency-review.yml b/.github/workflows/dependency-review.yml
index 2756e4bad..00e93c022 100644
--- a/.github/workflows/dependency-review.yml
+++ b/.github/workflows/dependency-review.yml
@@ -2,8 +2,11 @@ name: Dependency Review
 
 # SOC 2: dependency-review (OA-C-24). Flags vulnerable/denied deps on PRs.
 on:
+  # Every pull request, whatever its base, so a stacked PR reaches main with
+  # this required check already reported.
   pull_request:
-    branches: [main]
+  # The merge queue tests each group before it lands on main.
+  merge_group:
 
 permissions:
   contents: read
@@ -22,6 +25,16 @@ jobs:
       - name: Checkout
         uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - name: Dependency Review
+        if: github.event_name != 'merge_group'
         uses: actions/dependency-review-action@a1d282b36b6f3519aa1f3fc636f609c47dddb294 # v5.0.0
         with:
           fail-on-severity: high
+      # A queue group has no pull request in its payload: compare the group's
+      # head with the main commit it was built on.
+      - name: Dependency Review (merge queue group)
+        if: github.event_name == 'merge_group'
+        uses: actions/dependency-review-action@a1d282b36b6f3519aa1f3fc636f609c47dddb294 # v5.0.0
+        with:
+          fail-on-severity: high
+          base-ref: ${{ github.event.merge_group.base_sha }}
+          head-ref: ${{ github.event.merge_group.head_sha }}
diff --git a/.github/workflows/desktop-build.yml b/.github/workflows/desktop-build.yml
index 4d71509e2..a6ad7c6b9 100644
--- a/.github/workflows/desktop-build.yml
+++ b/.github/workflows/desktop-build.yml
@@ -35,12 +35,19 @@ jobs:
         env:
           BEFORE_SHA: ${{ github.event.before }}
           EVENT_NAME: ${{ github.event_name }}
+          GROUP_BASE_SHA: ${{ github.event.merge_group.base_sha }}
         shell: bash
         run: |
           set -euo pipefail
           changed_paths="${RUNNER_TEMP}/openadapt-desktop-changed-paths.txt"
           : > "${changed_paths}"
-          if [ "${EVENT_NAME}" = "push" ]; then
+          if [ "${EVENT_NAME}" = "merge_group" ]; then
+            # A queue group is scoped like a push to main: diff the group's
+            # head against the main commit it was built on.
+            BEFORE_SHA="${GROUP_BASE_SHA}"
+            git fetch --no-tags --depth=1 origin "${GROUP_BASE_SHA}" || true
+          fi
+          if [ "${EVENT_NAME}" = "push" ] || [ "${EVENT_NAME}" = "merge_group" ]; then
             before="${BEFORE_SHA}"
             if [ -z "${before}" ] || [ "${before}" = "0000000000000000000000000000000000000000" ]; then
               before="$(git rev-parse HEAD^)"
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index c59dcf0dd..ad5d5dfde 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -4,6 +4,8 @@ on:
   pull_request:
     branches:
       - '**'
+  # The merge queue tests each group before it lands on main.
+  merge_group:
   push:
     branches:
       - main
diff --git a/.github/workflows/packages.yml b/.github/workflows/packages.yml
index 5018e7046..e2d05bec4 100644
--- a/.github/workflows/packages.yml
+++ b/.github/workflows/packages.yml
@@ -46,6 +46,8 @@ name: Packages
 
 on:
   pull_request:
+  # The merge queue tests each group before it lands on main.
+  merge_group:
   push:
     branches: [main]
   workflow_dispatch:
@@ -86,6 +88,7 @@ jobs:
         env:
           EVENT_NAME: ${{ github.event_name }}
           BEFORE_SHA: ${{ github.event.before }}
+          GROUP_BASE_SHA: ${{ github.event.merge_group.base_sha }}
         run: |
           set -euo pipefail
           all() {
@@ -95,6 +98,13 @@ jobs:
           case "$EVENT_NAME" in
             workflow_dispatch) all ;;
             pull_request) base="HEAD^1" ;;  # the PR merge commit's first parent is the base tip
+            # A queue group runs the full matrix (the PR tier ran one lane)
+            # for every package the group's PRs touch, measured from the main
+            # commit the group was built on.
+            merge_group)
+              base="$GROUP_BASE_SHA"
+              git cat-file -e "$base^{commit}" 2>/dev/null || all
+              ;;
             *)
               if [ -z "${BEFORE_SHA:-}" ] || [ "$BEFORE_SHA" = 0000000000000000000000000000000000000000 ] \
                 || ! git cat-file -e "$BEFORE_SHA^{commit}" 2>/dev/null; then
diff --git a/.github/workflows/platform-manifest.yml b/.github/workflows/platform-manifest.yml
index 3b2083625..ac47179ec 100644
--- a/.github/workflows/platform-manifest.yml
+++ b/.github/workflows/platform-manifest.yml
@@ -8,6 +8,8 @@ on:
   pull_request:
     branches:
       - '**'
+  # The merge queue tests each group before it lands on main.
+  merge_group:
   push:
     branches:
       - main
diff --git a/.github/workflows/secret-scan.yml b/.github/workflows/secret-scan.yml
index 2d5db93f0..02212b5f3 100644
--- a/.github/workflows/secret-scan.yml
+++ b/.github/workflows/secret-scan.yml
@@ -6,6 +6,8 @@ name: Secret Scan
 # invoke it directly and pin the version. Scans full git history on PRs + main.
 on:
   pull_request:
+  # The merge queue tests each group before it lands on main.
+  merge_group:
   push:
     branches: [main]
 
diff --git a/packages/desktop/scripts/classify_build_changes.py b/packages/desktop/scripts/classify_build_changes.py
index 2c41eb576..308d51518 100644
--- a/packages/desktop/scripts/classify_build_changes.py
+++ b/packages/desktop/scripts/classify_build_changes.py
@@ -4,9 +4,10 @@
 request that changes the Tauri shell or its JavaScript locks also builds the
 Linux installer, so a native dependency bump compiles before it merges. Release
 candidates and explicit dispatches keep the complete platform matrix. A push
-to protected ``main`` repeats the expensive matrix only when a dependency,
-toolchain, packaging, or native-runtime input changed. The immutable native
-release workflow always rebuilds every installer from its release tag.
+to protected ``main``, and a merge queue group about to become ``main``,
+repeats the expensive matrix only when a dependency, toolchain, packaging, or
+native-runtime input changed. The immutable native release workflow always
+rebuilds every installer from its release tag.
 """
 
 from __future__ import annotations
@@ -123,7 +124,8 @@ def classify_build_scope(event: str, changed_paths: Iterable[str]) -> BuildScope
         if native:
             return BuildScope(True, True, f"pull request changes the native shell: {native[0]}")
         return BuildScope(True, False, "representative pull-request sidecar")
-    if event != "push":
+    # A merge queue group is about to become main, so it gets main's scope.
+    if event not in ("push", "merge_group"):
         return BuildScope(True, True, f"unknown event {event!r}; fail toward full evidence")
 
     if not paths:
diff --git a/packages/desktop/tests/test_build_change_classifier.py b/packages/desktop/tests/test_build_change_classifier.py
index 8e87ddd4b..fb39a156a 100644
--- a/packages/desktop/tests/test_build_change_classifier.py
+++ b/packages/desktop/tests/test_build_change_classifier.py
@@ -85,3 +85,10 @@ def test_empty_push_fails_toward_the_complete_matrix() -> None:
 def test_absolute_or_parent_path_is_refused() -> None:
     with pytest.raises(ValueError, match="repository-relative"):
         classify_build_scope("push", ["../outside"])
+
+
+def test_merge_queue_group_is_scoped_like_main() -> None:
+    assert classify_build_scope("merge_group", ["src/App.tsx"]) == classify_build_scope(
+        "push", ["src/App.tsx"]
+    )
+    assert classify_build_scope("merge_group", []).run_native is True