diff --git a/Gemfile b/Gemfile
index e381bc0..56b9775 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,20 +1,20 @@
-source 'https://rubygems.org'
+source ENV['GEM_SOURCE'] || "https://rubygems.org"
 
 group :development, :test do
   gem 'rake',                    :require => false
   gem 'rspec-puppet',            :require => false
   gem 'puppetlabs_spec_helper',  :require => false
   gem 'beaker',                  :require => false
   gem 'beaker-rspec',            :require => false
   gem 'puppet-lint',             :require => false
   gem 'serverspec',              :require => false
   gem 'pry',                     :require => false
 end
 
 if puppetversion = ENV['PUPPET_GEM_VERSION']
   gem 'puppet', puppetversion, :require => false
 else
   gem 'puppet', :require => false
 end
 
 # vim:ft=ruby