title: How to use actionpack (rails) as standalone?
body: <p>I want to use the <a href="https://github.com/rails/rails/tree/master/actionpack" rel="nofollow">actionpack</a> gem from ruby-on-rails as standalone component with a single file:</p>
  
  <pre><code>class ApplicationController &lt; ActionController::Metal
      def index
          self.response_body = 'Hello World'
      end
  end
  </code></pre>
  
  <p>There are only few examples on such as <a href="https://gist.github.com/josevalim/1942658" rel="nofollow">rails lightweight stack</a> which is outdated.</p>
  
  <p><strong>My question is now how I could bind the <code>ApplicationController</code> to a web server with routing capabilities. Similar with <code>bin/rails server</code> just without all the bloat.</strong></p>