diff --git a/Gemfile b/Gemfile
index 165a537..be82408 100644
--- a/Gemfile
+++ b/Gemfile
@@ -4,5 +4,6 @@ gem 'twitter', '~> 6.1.0'
 gem 't'
 gem 'asciidoctor-pdf'
 gem 'terjira'
+gem 'terraforming'
 #Previously installed using
 #sudo gem install -n /usr/local/bin asciidoctor-pdf --pre