diff --git a/.dockerignore b/.dockerignore
new file mode 100644
index 0000000..ddad3d9
--- /dev/null
+++ b/.dockerignore
@@ -0,0 +1,2 @@
+.*
+*
diff --git a/Dockerfile b/Dockerfile
index 6d7995e..43a6b9b 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,13 +1,14 @@
-FROM alpine:3.3
+FROM alpine:3.4
 MAINTAINER Alexey Diyan <alexey.diyan@gmail.com>
 
+# Install ca-certificates, required for the "release message" feature.
 RUN set -x \
-  && buildDeps='go git bzr' \
-  && apk add --update $buildDeps \
+  && apk add --no-cache ca-certificates \
+  && apk add --no-cache --virtual build-dependencies go git \
   && GOPATH=/tmp/gocode go get github.com/mailhog/MailHog \
   && mv /tmp/gocode/bin/MailHog /usr/local/bin/ \
-  && apk del $buildDeps \
-  && rm -rf /var/cache/apk/* /tmp/*
+  && apk --no-cache del --purge build-dependencies \
+  && rm -rf /tmp/*
 
 EXPOSE 1025 8025
 ENTRYPOINT ["MailHog"]