At work I had to set up a server with django, postgres, SSL, rabbitmq, celery and a few other things. I did it in both ansible and docker-compose, the ansible version was 1500 lines and docker-compose version was 100 lines. A lot of the ansible stuff is dealing with users, groups, services, supervisord, virtualenvs and repositories - none of this is required in docker as containers restart themselves, users are already set up, you don't need virtualenv, and using containers avoids the need to use repositories to get specific software versions. Also the docker-compose version was much faster to pick up changes, vs minutes for ansible.

I don't find docker that useful for developing on a day to dat basis however, it just gets in the way and generally you're not going to need a webserver, SSL, celery, rabbitmq in development anyway. It is useful to debug things locally though.

The other reason to use docker is state: while using ansible we got bitten by old dependencies hanging around because ansible doesn't exactly mirror your config, it can really only add stuff. Whereas docker actually wipes the slate clean every single deploy so your server is an exact mirror of your docker-compose file. This is really important.