diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index bfe0a8d..8134684 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -33,8 +33,8 @@ jobs:
       run: |
         case '${{ github.event_name }}' in
           push)
-            firstCommit='${{ github.event.commits[0].id }}'
-            lastCommit='${{ github.event.commits[-1].id }}'
+            firstCommit='${{ github.event.before }}'
+            lastCommit='${{ github.event.after }}'
             ;;
           pull_request)
             firstCommit='${{ github.event.pull_request.base.sha }}'