diff --git a/.forgejo/workflows/build.yml b/.forgejo/workflows/build.yml
index 55d623c..48c577d 100644
--- a/.forgejo/workflows/build.yml
+++ b/.forgejo/workflows/build.yml
@@ -21,7 +21,8 @@ jobs:
         id: generate-list
         shell: bash
         run: |
-          echo matrix="$(ls | jq -Rn '[inputs]')" >> "${GITHUB_OUTPUT}"
+          set -ex
+          echo matrix='$(ls | jq -Rn "[inputs]")' >> "${GITHUB_OUTPUT}"
 
   build:
     name: Build all images