diff --git a/docker/Dockerfile.cloud-agent b/docker/Dockerfile.cloud-agent
index 8f7434854..9d86a6ea7 100644
--- a/docker/Dockerfile.cloud-agent
+++ b/docker/Dockerfile.cloud-agent
@@ -1,7 +1,6 @@
 FROM alpine:3.7
 WORKDIR /home/weave
-RUN apk add --update bash conntrack-tools iproute2 util-linux curl && \
-	rm -rf /var/cache/apk/*
+RUN apk add --no-cache bash conntrack-tools iproute2 util-linux curl
 COPY ./scope /home/weave/
 ENTRYPOINT ["/home/weave/scope", "--mode=probe", "--no-app", "--probe.docker=true"]
 
diff --git a/docker/Dockerfile.scope b/docker/Dockerfile.scope
index 7e0af4571..b62c65c2f 100644
--- a/docker/Dockerfile.scope
+++ b/docker/Dockerfile.scope
@@ -1,8 +1,7 @@
 FROM weaveworks/cloud-agent
-RUN apk add --update runit && \
-	rm -rf /var/cache/apk/*
-ADD ./demo.json /
-ADD ./weave ./weaveutil /usr/bin/
+RUN apk add --no-cache runit
+COPY ./demo.json /
+COPY ./weave ./weaveutil /usr/bin/
 COPY ./runsvinit ./entrypoint.sh /home/weave/
 COPY ./run-app /etc/service/app/run
 COPY ./run-probe /etc/service/probe/run