diff --git a/.github/workflows/container-images.yml b/.github/workflows/container-images.yml
index 6829cff..fb74a88 100644
--- a/.github/workflows/container-images.yml
+++ b/.github/workflows/container-images.yml
@@ -8,6 +8,8 @@ on:
       - 'Gemfile'
       - 'Gemfile.lock'
       - 'package.json'
+    branches:
+      - 'master'
 
 jobs:
   build: