This advanced option let you configure the command to be ran when the container is started. This command
<b>must</b> hang so the container is alive, while build steps are executed using <code>docker exec</code>.
<p>
You should not change this option until you have some advanced requirements. For sample using
<a href="https://github.com/jpetazzo/dind">Docker in Docker</a> will require to configure command as
<code>wrapdocker /bin/cat</code>.