diff --git a/Makefile b/Makefile
index c172a4b..a14c8cd 100644
--- a/Makefile
+++ b/Makefile
@@ -80,7 +80,7 @@ test:
 
 test-linux: 
 	@for target in $(TARGETS); do                                                      \
-	  $(CMD_DIR)/$${target}/test.sh;                                                  \
+	  $(CMD_DIR)/$${target}/test.sh;                                                   \
 	done
 
 container: test-linux
diff --git a/build/charts/Dockerfile b/build/charts/Dockerfile
index a41d657..e2f4c44 100644
--- a/build/charts/Dockerfile
+++ b/build/charts/Dockerfile
@@ -1,10 +1,4 @@
-FROM cargo.caicloud.xyz/library/debian:stretch
-
-RUN apt-get update && \
-    apt-get install -y ruby --force-yes&& \
-    apt-get clean && \
-    rm -rf /var/lib/apt/lists/*
-LABEL maintainer="Wei Guo <guowei@caicloud.io>"
+FROM cargo.caicloud.xyz/library/debian:stretch-ruby
 
 COPY build/charts/build.sh /build.sh
 COPY stable /stable