diff --git a/.gitignore b/.gitignore
index 60813275..14c68493 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,10 +8,10 @@
 #  state you decide you never want mirrored.)
 
 # run-firestorm skill screenshots (may capture the operator's desktop -- never mirror)
-.claude/skills/run-firestorm/shots/
+.claude/skills/run-firestorm/shots/
 
 # FS507D_20161015: later FireStorm release drop, kept local for analysis -- not part of the mirror
-FS507D_20161015/
+FS507D_20161015/
 
 # player-created mechlab variants in the game deploy (local test/play data, per-machine)
 MW4/Resource/Variants/
@@ -19,3 +19,7 @@ MW4/Resource/Variants/
 # GameOS run-time reports: rewritten on every launch, per-machine
 MW4/gos-displays.txt
 MW4/gos-fps.txt
+
+# Python bytecode cache: regenerated on import, and the filename is interpreter-specific
+__pycache__/
+*.pyc
diff --git a/build-env/__pycache__/replay-mr.cpython-314.pyc b/build-env/__pycache__/replay-mr.cpython-314.pyc
deleted file mode 100644
index f147979e..00000000
Binary files a/build-env/__pycache__/replay-mr.cpython-314.pyc and /dev/null differ
diff --git a/build-env/__pycache__/variant-to-subsystems.cpython-314.pyc b/build-env/__pycache__/variant-to-subsystems.cpython-314.pyc
deleted file mode 100644
index 9251e75f..00000000
Binary files a/build-env/__pycache__/variant-to-subsystems.cpython-314.pyc and /dev/null differ