diff --git a/bin/assert-no-changes.sh b/bin/assert-no-changes.sh
index 5abb859..d4f9a9a 100755
--- a/bin/assert-no-changes.sh
+++ b/bin/assert-no-changes.sh
@@ -9,6 +9,7 @@ for proto in $(find ./rbproto -iname '*.proto'); do
 		protoc -I=./rbproto --python_out=./rbproto/python --pyi_out=./rbproto/python ./rbproto/shot.proto
     yarn pbjs ./rbproto/shot.proto --ts ./rbproto/ts/shot.ts
 done
+pip install black >/dev/null 2>&1 || true
 black rbproto/python
 prettier ./rbproto --write