diff --git a/docker/Dockerfile b/docker/Dockerfile
index e4f5714..5bb8ddb 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,3 +1,7 @@
 FROM ruby:2.1
-RUN gem install wayback_machine_downloader
+COPY ../ /build
+RUN cd build && \
+    bundle install && \
+    cd .. && \
+    rm -rf build
 ENTRYPOINT [ "/usr/local/bundle/bin/wayback_machine_downloader" ]