diff --git a/treefmt.nix b/treefmt.nix
index c81a23d..084c2fb 100644
--- a/treefmt.nix
+++ b/treefmt.nix
@@ -10,4 +10,9 @@
     shellcheck.enable = true;
     deadnix.enable = true;
   };
+  settings = {
+    global.excludes = [
+      "*.lock"
+    ];
+  };
 }