[ArtWomb]

Strong recommend for Autolab as well. In addition to the features above. Front end is also easily extensible for custom activities.

Behind the scenes of course, are Docker multi-stage builds for submitted code. And I dare say, if your class is <1000 students. You can roll your own build environment on a single small cloud instance.

http://autolab.github.io/2015/05/autolab-and-docker/