diff --git a/Dockerfile.www-gitlab-com b/Dockerfile.www-gitlab-com
index 9f48df9..eaabad8 100644
--- a/Dockerfile.www-gitlab-com
+++ b/Dockerfile.www-gitlab-com
@@ -1,6 +1,6 @@
 FROM ruby:2.3-slim
 
-ENV PACKAGES="git-core pandoc texlive-latex-recommended texlive-xetex texlive-fonts-recommended lmodern ed"
+ENV PACKAGES="git-core pandoc texlive-latex-recommended texlive-xetex texlive-fonts-recommended lmodern ed file"
 
 ADD / /
 RUN /scripts/install-www-gitlab-com