diff --git a/.gitignore b/.gitignore
index 22971e97..edf0755c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -26,3 +26,6 @@ data/
 .git-next.toml
 .envrc
 *.profraw
+
+mutants.out/
+mutants.out.old/