Docker: how to manage development and production settings?
<p>I'm just getting started with Docker. With the official NGINX image on my OSX development machine (with Docker Machine as the Docker host) I ran up against the bug with <code>sendfile</code> and VirtualBox which means the server fails to show changes I make to files. </p>

<p>The workaround for this is to use a modified nginx.conf file that turns off <code>sendfile</code>. <a href="https://ejf.io/dev_blog/docker_nginx_caching/" rel="noreferrer">This guy's solution</a> has an instruction in the Dockerfile to copy a customised conf file into the container. Alternatively, <a href="http://mflo.io/2015/06/28/nocache-nginx-docker-container/" rel="noreferrer">this guy</a> maps the NGINX configuration to a new folder with modified conf file. </p>

<p>This kind of thing works OK locally. But what if I don't need this modification on my cloud host? How should I handle this and other differences when it comes to deployment?</p>