diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index 0409abf0..ef6ccb02 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -3,6 +3,9 @@ name: Frontend checks
 on:
   pull_request:
     branches: [main, dev]
+  # The merge queue builds main plus the queued pull requests on a temporary
+  # branch and only counts checks that ran on the merge_group event.
+  merge_group:
   push:
     branches: [main]
   workflow_dispatch: {}
@@ -32,6 +35,7 @@ jobs:
     #
     # GOVERNANCE_BASE points the changed-file gate at the right diff:
     #   PR  -> the PR target branch (origin/<base_ref>)
+    #   merge group -> the group's own base (github.event.merge_group.base_sha)
     #   push-> the previous commit on the branch (github.event.before)
     #   manual -> main, for exact-head recovery runs
     runs-on: ubuntu-latest
@@ -46,10 +50,13 @@ jobs:
           EVENT_NAME: ${{ github.event_name }}
           EVENT_BEFORE: ${{ github.event.before }}
           PR_BASE_SHA: ${{ github.event.pull_request.base.sha }}
+          MERGE_GROUP_BASE_SHA: ${{ github.event.merge_group.base_sha }}
         run: |
           set -euo pipefail
           if [[ "${EVENT_NAME}" == "pull_request" ]]; then
             base="${PR_BASE_SHA}"
+          elif [[ "${EVENT_NAME}" == "merge_group" && -n "${MERGE_GROUP_BASE_SHA}" ]]; then
+            base="${MERGE_GROUP_BASE_SHA}"
           elif [[ "${EVENT_NAME}" == "push" && -n "${EVENT_BEFORE}" && ! "${EVENT_BEFORE}" =~ ^0+$ ]]; then
             base="${EVENT_BEFORE}"
           else