diff --git a/docker/shadowsocks-libev/Dockerfile b/docker/shadowsocks-libev/Dockerfile
index 9f7fe93..3840359 100644
--- a/docker/shadowsocks-libev/Dockerfile
+++ b/docker/shadowsocks-libev/Dockerfile
@@ -7,10 +7,10 @@ FROM debian:stretch
 MAINTAINER Teddysun <i@teddysun.com>
 
 RUN set -ex; \
-    printf "deb http://deb.debian.org/debian stretch-backports main" > /etc/apt/sources.list.d/stretch-backports.list; \
-    apt-get update; \
-    apt-get -t stretch-backports install -y shadowsocks-libev simple-obfs; \
-    rm -rf /var/lib/apt/lists/*;
+    && printf "deb http://deb.debian.org/debian stretch-backports main" > /etc/apt/sources.list.d/stretch-backports.list; \
+    && apt-get update; \
+    && apt-get -t stretch-backports install -y --no-install-recommends shadowsocks-libev simple-obfs; \
+    && rm -rf /var/lib/apt/lists/*
 
 COPY ./config_sample.json /etc/shadowsocks-libev/config.json
 VOLUME /etc/shadowsocks-libev
diff --git a/docker/shadowsocks-r/Dockerfile b/docker/shadowsocks-r/Dockerfile
index 6740c37..a8547f7 100644
--- a/docker/shadowsocks-r/Dockerfile
+++ b/docker/shadowsocks-r/Dockerfile
@@ -7,14 +7,14 @@ FROM debian:stretch
 MAINTAINER Teddysun <i@teddysun.com>
 
 RUN set -ex; \
-    apt-get update; \
-    apt-get install -y wget python libsodium-dev openssl; \
-    rm -rf /var/lib/apt/lists/*; \
-    wget -O /tmp/shadowsocksr-3.2.2.tar.gz https://github.com/shadowsocksrr/shadowsocksr/archive/3.2.2.tar.gz; \
-    tar zxf /tmp/shadowsocksr-3.2.2.tar.gz -C /tmp; \
-    mv /tmp/shadowsocksr-3.2.2/shadowsocks /usr/local/; \
-    rm -fr /tmp/shadowsocksr-3.2.2; \
-    rm -f /tmp/shadowsocksr-3.2.2.tar.gz;
+    && apt-get update; \
+    && apt-get install -y wget python libsodium-dev openssl; \
+    && rm -rf /var/lib/apt/lists/*; \
+    && wget -O /tmp/shadowsocksr-3.2.2.tar.gz https://github.com/shadowsocksrr/shadowsocksr/archive/3.2.2.tar.gz; \
+    && tar zxf /tmp/shadowsocksr-3.2.2.tar.gz -C /tmp; \
+    && mv /tmp/shadowsocksr-3.2.2/shadowsocks /usr/local/; \
+    && rm -fr /tmp/shadowsocksr-3.2.2; \
+    && rm -f /tmp/shadowsocksr-3.2.2.tar.gz
 
 COPY ./config_sample.json /etc/shadowsocks-r/config.json
 VOLUME /etc/shadowsocks-r