diff --git a/Makefile b/Makefile
index 102e04f..769f5bf 100644
--- a/Makefile
+++ b/Makefile
@@ -49,7 +49,7 @@ install:
 
 .PHONY: docker-login
 docker-login:
-	echo $DOCKER_PASS | docker login -u $DOCKER_USER --password-stdin
+	echo ${DOCKER_PASS} | docker login -u ${DOCKER_USER} --password-stdin
 
 .PHONY: docker-images
 docker-images: