diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 9d74be3..99eaafa 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -43,7 +43,9 @@ We actively welcome your pull requests.
 1. Fork the repo and create your branch from `main`.
 2. If you've added code that should be tested, add tests.
 3. If you've changed or added exported functions or types, document them.
-4. Ensure the test suite passes (`make ci`).
+4. We use [gofumpt](https://github.com/mvdan/gofumpt) to format our code. Don't forget to always run `make fmt` before opening a new PR.
+5. Ensure the test suite passes and the linter doesn't complain (`make ci`).
+
 
 ## Issues