diff --git a/.github/workflows/haskell-ci.yml b/.github/workflows/haskell-ci.yml
index 235d5bbb..31a4efa8 100644
--- a/.github/workflows/haskell-ci.yml
+++ b/.github/workflows/haskell-ci.yml
@@ -18,6 +18,9 @@ on:
   pull_request:
     branches:
       - master
+  merge_group:
+    branches:
+      - master
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/all-versions.github b/fixtures/all-versions.github
index 655cfce4..5a4fe3ae 100644
--- a/fixtures/all-versions.github
+++ b/fixtures/all-versions.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/conditionals.github b/fixtures/conditionals.github
index dbb8a9bf..a1b17e29 100644
--- a/fixtures/conditionals.github
+++ b/fixtures/conditionals.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/copy-fields-all.github b/fixtures/copy-fields-all.github
index b844ecf1..a08058fa 100644
--- a/fixtures/copy-fields-all.github
+++ b/fixtures/copy-fields-all.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/copy-fields-none.github b/fixtures/copy-fields-none.github
index e30cbb30..fd6dad74 100644
--- a/fixtures/copy-fields-none.github
+++ b/fixtures/copy-fields-none.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/copy-fields-some.github b/fixtures/copy-fields-some.github
index d6456a5a..67ac81e1 100644
--- a/fixtures/copy-fields-some.github
+++ b/fixtures/copy-fields-some.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/doctest-version.github b/fixtures/doctest-version.github
index f75cbc66..372c1651 100644
--- a/fixtures/doctest-version.github
+++ b/fixtures/doctest-version.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/doctest.github b/fixtures/doctest.github
index 6eaa4115..5431a5e1 100644
--- a/fixtures/doctest.github
+++ b/fixtures/doctest.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/empty-line.github b/fixtures/empty-line.github
index 38424e9a..b45619a7 100644
--- a/fixtures/empty-line.github
+++ b/fixtures/empty-line.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/enabled-jobs.github b/fixtures/enabled-jobs.github
index 9283ebdd..a59753a6 100644
--- a/fixtures/enabled-jobs.github
+++ b/fixtures/enabled-jobs.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/fail-versions.github b/fixtures/fail-versions.github
index e35abf7d..cff6f914 100644
--- a/fixtures/fail-versions.github
+++ b/fixtures/fail-versions.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/irc-channels.github b/fixtures/irc-channels.github
index 51bb6b5e..66fe6c5c 100644
--- a/fixtures/irc-channels.github
+++ b/fixtures/irc-channels.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   irc:
     name: Haskell-CI (IRC notification)
diff --git a/fixtures/messy.github b/fixtures/messy.github
index bff237bf..b7d52daf 100644
--- a/fixtures/messy.github
+++ b/fixtures/messy.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/psql.github b/fixtures/psql.github
index fb0debfd..9bcf2088 100644
--- a/fixtures/psql.github
+++ b/fixtures/psql.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/fixtures/travis-patch.github b/fixtures/travis-patch.github
index 038a3d90..fe26281f 100644
--- a/fixtures/travis-patch.github
+++ b/fixtures/travis-patch.github
@@ -16,6 +16,7 @@ name: Haskell-CI
 on:
   - push
   - pull_request
+  - merge_group
 jobs:
   linux:
     name: Haskell-CI - Linux - ${{ matrix.compiler }}
diff --git a/haskell-ci.cabal b/haskell-ci.cabal
index 5265a0ee..500bae83 100644
--- a/haskell-ci.cabal
+++ b/haskell-ci.cabal
@@ -1,6 +1,6 @@
 cabal-version:      2.2
 name:               haskell-ci
-version:            0.19.20250916
+version:            0.19.20250917
 synopsis:           Haskell CI script generator
 description:
   Script generator (@haskell-ci@) for
diff --git a/src/HaskellCI/GitHub/Yaml.hs b/src/HaskellCI/GitHub/Yaml.hs
index adb4a145..000b715f 100644
--- a/src/HaskellCI/GitHub/Yaml.hs
+++ b/src/HaskellCI/GitHub/Yaml.hs
@@ -96,11 +96,12 @@ instance ToYaml GitHub where
 instance ToYaml GitHubOn where
     toYaml GitHubOn {..}
         | null ghBranches
-        = ylistFilt [] ["push", "pull_request"]
+        = ylistFilt [] ["push", "pull_request", "merge_group"]
         | otherwise
         = ykeyValuesFilt []
               [ "push"         ~> branches
               , "pull_request" ~> branches
+              , "merge_group"  ~> branches
               ]
       where
         branches = ykeyValuesFilt []