diff --git a/Library/Homebrew/formulary.rb b/Library/Homebrew/formulary.rb
index 984cac9ce5..6b1b7de994 100644
--- a/Library/Homebrew/formulary.rb
+++ b/Library/Homebrew/formulary.rb
@@ -1,5 +1,6 @@
 require "digest/md5"
 require "formula_renames"
+require "tap"
 
 # The Formulary is responsible for creating instances of Formula.
 # It is not meant to be used directy from formulae.