diff --git a/lib/omniauth-slack.rb b/lib/omniauth-slack.rb
new file mode 100644
index 0000000..8da1d60
--- /dev/null
+++ b/lib/omniauth-slack.rb
@@ -0,0 +1,2 @@
+require 'omniauth-slack/version'
+require 'omniauth/strategies/slack'
\ No newline at end of file
diff --git a/lib/omniauth/slack/version.rb b/lib/omniauth-slack/version.rb
similarity index 100%
rename from lib/omniauth/slack/version.rb
rename to lib/omniauth-slack/version.rb
diff --git a/lib/omniauth/slack.rb b/lib/omniauth/slack.rb
deleted file mode 100644
index fcbf487..0000000
--- a/lib/omniauth/slack.rb
+++ /dev/null
@@ -1,7 +0,0 @@
-require "omniauth/slack/version"
-
-module Omniauth
-  module Slack
-    # Your code goes here...
-  end
-end
diff --git a/lib/omniauth/strategies/slack.rb b/lib/omniauth/strategies/slack.rb
new file mode 100644
index 0000000..67d0d4e
--- /dev/null
+++ b/lib/omniauth/strategies/slack.rb
@@ -0,0 +1,27 @@
+require 'omniauth/strategies/oauth2'
+
+module OmniAuth
+  module Strategies
+    class Slack < OmniAuth::Strategies::OAuth2
+
+      option :name, "slack"
+
+      option :client_options, {
+        site: "https://slack.com",
+        token_url: "/api/oauth.access"
+      }
+
+      option :auth_token_params, {
+        mode: :query,
+        param_name: 'token'
+      }
+
+      extra do
+        {
+          'members' => access_token.get('/api/users.list').parsed['members']
+        }
+      end
+
+    end
+  end
+end
\ No newline at end of file
diff --git a/omniauth-slack.gemspec b/omniauth-slack.gemspec
index 17603c9..8a0d0a1 100644
--- a/omniauth-slack.gemspec
+++ b/omniauth-slack.gemspec
@@ -1,16 +1,14 @@
 # coding: utf-8
-lib = File.expand_path('../lib', __FILE__)
-$LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
-require 'omniauth/slack/version'
+require File.expand_path('../lib/omniauth-slack/version', __FILE__)
 
 Gem::Specification.new do |spec|
   spec.name          = "omniauth-slack"
   spec.version       = Omniauth::Slack::VERSION
   spec.authors       = ["kimura"]
   spec.email         = ["kimura@enigmo.co.jp"]
-  spec.description   = %q{TODO: Write a gem description}
-  spec.summary       = %q{TODO: Write a gem summary}
-  spec.homepage      = ""
+  spec.description   = %q{OmniAuth strategy for Slack}
+  spec.summary       = %q{OmniAuth strategy for Slack}
+  spec.homepage      = "https://github.com/kmrshntr/omniauth-slack.git"
   spec.license       = "MIT"
 
   spec.files         = `git ls-files`.split($/)
@@ -18,6 +16,8 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ["lib"]
 
+  spec.add_runtime_dependency 'omniauth-oauth2' "~> 1.1.2"
+
   spec.add_development_dependency "bundler", "~> 1.3"
   spec.add_development_dependency "rake"
 end