[michaelmior]

I haven't really looked closely at Drone yet, but you might also be interested in Strider. http://stridercd.com/

One of the things I like is that it's dead simple to get running on Heroku. Language support is a little weak (Python, Ruby, node.js), but we're working on that.

Another nice feature that's currently lacking which it looks like Drone does well is the ability to provision external services (e.g. DB servers) for tests.