[esamatti]

The big point of Docker for me is that I can build the container on my machine, run automated tests on it, play with it and then ship it to the production machines when I'm confident that it is working.

If you build the container on a service like this testing it is hard or in some cases even impossible. For example acceptance tests with Selenium.

Gemfile.lock and similar version binding tools help, but prebuild containers bring the deployment stability to whole new level and is the reason why I'm exited about Docker and containers in general.

Do they support prebuild containers?

[lhc-]

"You can create a Docker file with some easy steps we’ve created, or you can upload your own Docker file and create an instance from that."

Sounds like a yes.

[lotyrin]

Well, no. A Dockerfile is the build instructions, not the build artifact.

[sams99]

you can commit at any point and ship that via private registry