diff --git a/.github/workflows/nix.yml b/.github/workflows/nix.yml
index 25c8d7c..a546bb3 100644
--- a/.github/workflows/nix.yml
+++ b/.github/workflows/nix.yml
@@ -34,4 +34,4 @@ jobs:
     steps:
       - uses: actions/checkout@v4
       - uses: cachix/install-nix-action@v31
-      - run: nix shell nixpkgs#alejandra -c alejandra -c .
+      - run: nix run nixpkgs#nixfmt-tree -- --ci