Develop Wordpress plugins, themes with Docker
github.com
This is the same setup someone might use with Vagrant. Just much faster, thanks to lxc and docker.
github.com
Other projects with same functionality:
Just click a button on your hosting CPanel, install wordpress and get off to the races in an environment as close to production as you can get.
Perhaps there are other (better) uses for docker, but Wordpress development in unlikely to become a pathway for docker adaptation.
Zpanel is free as well.