diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 47ffd46..f08c69f 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -13,9 +13,8 @@ env:
 
 jobs:
   if_release:
-    if: |
-        ${{ github.event.pull_request.merged == true }}
-        && ${{ contains(github.event.pull_request.labels.*.name, 'release') }}
+    # Disallow publishing from branches that aren't `master`.
+    if: github.ref == 'refs/heads/master'
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3