diff --git a/Gemfile b/Gemfile
index 23cbd62..f2c3ce8 100644
--- a/Gemfile
+++ b/Gemfile
@@ -19,6 +19,7 @@ end
 
 group :test do
   gem "autodoc"
+  gem "coveralls", require: false
   gem "factory_girl_rails"
   gem "response_code_matchers"
   gem "rspec-json_matcher"
diff --git a/README.md b/README.md
index 632a866..d5a350b 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# Magi [![Build Status](https://travis-ci.org/r7kamura/magi.png?branch=master)](https://travis-ci.org/r7kamura/magi) [![Code Climate](https://codeclimate.com/github/r7kamura/magi.png)](https://codeclimate.com/github/r7kamura/magi)
+# Magi [![Build Status](https://travis-ci.org/r7kamura/magi.png?branch=master)](https://travis-ci.org/r7kamura/magi) [![Code Climate](https://codeclimate.com/github/r7kamura/magi.png)](https://codeclimate.com/github/r7kamura/magi) [![Coverage Status](https://coveralls.io/repos/r7kamura/magi/badge.png)](https://coveralls.io/r/r7kamura/magi)
 Casual CI server system (magi is a temporal name).
 
 ## Usage
diff --git a/spec/spec_helper.rb b/spec/spec_helper.rb
index 1be7c4a..3395bfa 100644
--- a/spec/spec_helper.rb
+++ b/spec/spec_helper.rb
@@ -1,3 +1,6 @@
+require "coveralls"
+Coveralls.wear!
+
 require "simplecov"
 SimpleCov.start