diff --git a/post_commit_hook.rb b/post_commit_hook.rb
index 9701384..e550769 100644
--- a/post_commit_hook.rb
+++ b/post_commit_hook.rb
@@ -1,5 +1,6 @@
 #!/usr/bin/env ruby
 
+require 'rubygems'
 require 'grit'
 include Grit