diff --git a/spec/dns_spec.rb b/spec/dns_spec.rb
index e04a363..038f83a 100644
--- a/spec/dns_spec.rb
+++ b/spec/dns_spec.rb
@@ -1,4 +1,5 @@
 require File.expand_path('../spec_helper', __FILE__)
+require 'tempfile'
 
 VALID_DOMAIN = "google.com"
 INVALID_DOMAIN = "gibidigibigididibitidibigitibidigitidididi.com"