diff --git a/Gemfile b/Gemfile
index 3ff534f..740e650 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,3 +1,3 @@
-source :rubygems
+source 'https://rubygems.org'
 
 gem 'rspec', '~> 2.7.0'
diff --git a/Gemfile.lock b/Gemfile.lock
index 0b61e1c..e8df347 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,5 +1,5 @@
 GEM
-  remote: http://rubygems.org/
+  remote: https://rubygems.org/
   specs:
     diff-lcs (1.1.3)
     rspec (2.7.0)