diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c281746..e628324 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -16,6 +16,6 @@ jobs:
       with:
         CACHIX_SIGNING_KEY: ${{ secrets.CACHIX_SIGNING_KEY }}
     - name: "Check Haskell formatting"
-      run: ./script/fmt -c
+      run: nix run -c "script/fmt -c"
     - name: "Run tests"
       run: ./script/test