diff --git a/.gitignore b/.gitignore
index d6d2a48..e4e934e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -7,3 +7,8 @@ run.sh
 !.gitattributes
 !.github
 CLAUDE.md
+
+# The cutover rehearsal writes its fixture and state here.
+tools/fork/cutover-rehearsal/__pycache__/
+tools/fork/cutover-rehearsal/before.json
+tools/fork/cutover-rehearsal/phase2_notes.json