diff --git a/.github/workflows/backend.yml b/.github/workflows/backend.yml
index 2e64f4686..46a390fa6 100644
--- a/.github/workflows/backend.yml
+++ b/.github/workflows/backend.yml
@@ -2,6 +2,7 @@
 name: 'build backend container images'
 
 on:
+  pull_request:
   push:
     branches:
       - master