diff --git a/Gemfile b/Gemfile
index 6bb9eb9..924f4eb 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,2 +1,4 @@
 gem 'github-pages'
 source 'https://rubygems.org'
+
+gem "webrick", "~> 1.7"
diff --git a/_config.yml b/_config.yml
index 489d9a3..1c3e6fc 100644
--- a/_config.yml
+++ b/_config.yml
@@ -13,7 +13,6 @@ author :
   name : Karl Broman
   email : kbroman@gmail.com
   github : kbroman
-  twitter : kwbroman
   feedburner : nil
 
 production_url : https://kbroman.github.io/github_tutorial