I wrote a blog post on running pimatic in a docker container on a pi. The post includes example code and the docker images are on dockerhub. My main reason for doing this is being able to quickly setup a new pimatic instance without having to wait for npm install. Secondly, I just wanted to leran more about docker 
Read my blog post at http://www.hendriks.software/pimatic-using-docker-on-a-raspberry-pi/
Any feedback is very welcome!