diff --git a/.github/workflows/nix.yml b/.github/workflows/nix.yml
index e1684c3..87a69fb 100644
--- a/.github/workflows/nix.yml
+++ b/.github/workflows/nix.yml
@@ -39,7 +39,7 @@ jobs:
           name: nixsgx
           extraPullNames: vault-auth-tee
 
-      - run: nix fmt
+      - run: nix fmt . -- --check
 
   clippy:
     runs-on: ubuntu-latest