diff --git a/flake/dev/fmt.nix b/flake/dev/fmt.nix
index 274d2a0a..876ac779 100644
--- a/flake/dev/fmt.nix
+++ b/flake/dev/fmt.nix
@@ -66,6 +66,7 @@
           formatter.nixf-diagnose.options = [
             "--auto-fix"
             "--ignore=sema-unused-def-lambda-witharg-formal"
+            "--ignore=sema-primop-overridden"
           ];
         };
       };