diff --git a/Makefile b/Makefile
index b9968ae..ba1ccc8 100644
--- a/Makefile
+++ b/Makefile
@@ -8,7 +8,7 @@ ifndef BOX_INSTALLED
 endif
 
 build: check_box_installed
-	mkdir build
+	mkdir -p build
 	composer.phar update --no-dev -o
 	box build -v