diff --git a/docker/Dockerfile b/docker/Dockerfile
index b0b4d97d..1b19860b 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -10,5 +10,5 @@ ENV DATABASE_CLEANER_ALLOW_REMOTE_DATABASE_URL true
 
 COPY ./ /srv/app/datagovuk_publish
 
-RUN gem install bundler --conservative && \
-    bundle install
+RUN bash -c "gem install bundler && \
+    bundle install"