anchor.diff:  On the command line, use the `-c` option to specify the custom start command as the following example shows:
   
   <pre class="terminal">
  -$ cf push my-App -c "bundle exec rake VERBOSE=true"
  +$ cf push my-app -c "bundle exec rake VERBOSE=true"
   </pre>
   
   <p class="note"><strong>Note</strong>: The <code>-c</code> option with a value of 'null' forces <code>cf push</code> to use the buildpack start command. See <a href="./app-startup.html">About Starting Applications</a> for more information.</p>
  
positive.code:   ...
    env:
      RAILS_ENV: production
      RACK_ENV: production 
  </pre>
  
  `cf push` deploys the application to a container on the server. The variables belong to the container environment.
  
negative.code: 
  <pre>
  ---
    ...
    domains:
    - domain-example1.com
    - domain-example2.org
  