diff --git a/Gemfile b/Gemfile
index 3790b33e5..e5df66504 100644
--- a/Gemfile
+++ b/Gemfile
@@ -2,12 +2,3 @@ source 'https://rubygems.org'
 
 # Specify your gem's dependencies in git_stats.gemspec
 gemspec
-
-
-group :test do
-  gem 'rake'
-  gem 'pry'
-  gem 'rspec'
-  gem 'factory_girl'
-  gem 'simplecov'
-end
\ No newline at end of file
diff --git a/git_stats.gemspec b/git_stats.gemspec
index 22df06804..c631e7069 100644
--- a/git_stats.gemspec
+++ b/git_stats.gemspec
@@ -19,12 +19,18 @@ Gem::Specification.new do |gem|
 
   gem.required_ruby_version = Gem::Requirement.new(">= 1.9.2")
 
-  gem.add_dependency('activesupport', '>= 4.0')
-  gem.add_dependency('actionpack', '>= 4.0')
-  gem.add_dependency('tilt', '>= 1.4')
-  gem.add_dependency('haml', '>= 4.0')
-  gem.add_dependency('lazy_high_charts', '>= 1.4')
-  gem.add_dependency('i18n')
-  gem.add_dependency('thor')
-  gem.add_dependency('json_pure')
+  gem.add_dependency('actionpack', '~> 4.2')
+  gem.add_dependency('activesupport', '~> 4.2')
+  gem.add_dependency('haml', '~> 5.0')
+  gem.add_dependency('i18n', '~> 0.8')
+  gem.add_dependency('json_pure', '~> 2.1')
+  gem.add_dependency('lazy_high_charts', '~> 1.5')
+  gem.add_dependency('thor', '~> 0.20')
+  gem.add_dependency('tilt', '~> 2.0')
+
+  gem.add_development_dependency('factory_girl', '~> 4.7')
+  gem.add_development_dependency('pry', '~> 0.11')
+  gem.add_development_dependency('rake', '~> 12.0')
+  gem.add_development_dependency('rspec', '~> 3.4')
+  gem.add_development_dependency('simplecov', '~> 0.11')
 end