diff --git a/treefmt.nix b/treefmt.nix
index 587e79c..e5b57ee 100644
--- a/treefmt.nix
+++ b/treefmt.nix
@@ -33,7 +33,7 @@
           options = [
             "-eucx"
             ''
-              ${lib.getExe pkgs.ruff} --fix "$@"
+              ${lib.getExe pkgs.ruff} check "$@"
               ${lib.getExe pkgs.ruff} format "$@"
             ''
             "--" # this argument is ignored by bash