diff --git a/.github/workflows/check.yml b/.github/workflows/check.yml
index 8b7f67d..b6169a8 100644
--- a/.github/workflows/check.yml
+++ b/.github/workflows/check.yml
@@ -14,12 +14,24 @@ jobs:
         uses: actions/checkout@v3
       - name: Static Analysis
         uses: pre-commit/action@v3.0.0
+      - name: Dummy secrets file
+        run: |
+          tee -a .openchallenges > /dev/null <<EOT
+          MARIADB_PASSWORD=dummy
+          MARIADB_ROOT_PASSWORD=dummy
+          GIT_HOST_KEY=DUMMY_GIT_HOST_KEY
+          GIT_PRIVATE_KEY=-----BEGIN OPENSSH PRIVATE KEY-----\nDUMMY_GIT_PRIVATE_KEY\n-----END OPENSSH PRIVATE KEY-----
+          AWS_LOADER_S3_ACCESS_KEY_ID=DUMMY_S3_ACCESS_KEY
+          AWS_LOADER_S3_SECRET_ACCESS_KEY=DUMMY_S3_SECRET_KEY
+          SECURITY_KEY=00000
+          EOT
       - name: cdk synth
         uses: youyo/aws-cdk-github-actions@v2
         with:
           cdk_subcommand: 'synth'
           actions_comment: false
-          cdk_args: '--verbose'
+          debug_log: true
+          cdk_args: '--output ./cdk.out'
   tests:
     runs-on: ubuntu-latest
     steps: