Cool to see the authors of both vagrant and docker contribute their answers to the question.<p>I've actually been running docker containers inside of vagrant for a few months now at work. We're moving to a service oriented architecture and the more services we add the more complex it becomes for us to get new engineers up and running on their development environment.<p>We're using docker-compose to orchestrate all of the services inside of vagrant and it's been working so far for our development environments. Our next step is to switch our staging servers over to docker containers once we get all our engineers running vagrant + docker locally.