diff --git a/concourse/images/bundle-install.step b/concourse/images/bundle-install.step
index 42b3a415c3..052e2eccec 100644
--- a/concourse/images/bundle-install.step
+++ b/concourse/images/bundle-install.step
@@ -1,7 +1,8 @@
 # -*- dockerfile -*-
 
-COPY Gemfile      nokogiri/
+COPY Gemfile nokogiri/
 COPY Gemfile.lock nokogiri/
+COPY nokogiri.gemspec nokogiri/
 
 RUN gem install bundler -v "$(grep -A 1 "BUNDLED WITH" nokogiri/Gemfile.lock | tail -n 1)"
 RUN cd nokogiri && bundle install