diff --git a/Gemfile b/Gemfile
index 0a5465e..d1715ca 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,8 +2,3 @@ source 'http://rubygems.org/'
 
 # Specify your gem's dependencies in time_ext.gemspec
 gemspec
-
-group :development do
-  gem 'rspec', '>= 2.1.0'
-  gem 'yard', '>= 0.6.3'
-end
diff --git a/time_ext.gemspec b/time_ext.gemspec
index 8bf27f0..50b5317 100644
--- a/time_ext.gemspec
+++ b/time_ext.gemspec
@@ -21,4 +21,7 @@ Gem::Specification.new do |s|
   
   s.add_runtime_dependency 'activesupport', '>= 2.3.0'
   s.add_runtime_dependency 'i18n', '>= 0.4.2'
+  
+  s.add_development_dependency 'rspec', '>= 2.1.0'
+  s.add_development_dependency 'yard', '>= 0.6.3'
 end