diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 12b55ec..32cb628 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -34,4 +34,4 @@ jobs:
         run: npx tree-sitter test
 
       - name: Check formatting
-        run: npm run format-check
+        run: npx prettier --trailing-comma es5 --check grammar.js