diff --git a/Makefile b/Makefile
index 83646b4..4b768fd 100644
--- a/Makefile
+++ b/Makefile
@@ -13,7 +13,7 @@ clean:
 	for p in $(MAKEABLE_PACKAGES); do $(MAKE) -C packages/$$p clean; done
 
 bootstrap:
-	npm i .
+	[ -d node_modules/lerna ] || npm i .
 	npx lerna bootstrap
 
 .PHONY: bootstrap