diff --git a/.github/workflows/black.yml b/.github/workflows/black.yml
index b5edf27..a25f477 100644
--- a/.github/workflows/black.yml
+++ b/.github/workflows/black.yml
@@ -9,6 +9,6 @@ jobs:
       - uses: actions/checkout@v2
       - uses: psf/black@stable
         with:
-          options: "--check --verbose"
+          options: "--check --verbose --diff"
           src: ". vppcfg"