For decades we've followed and benefited from many of the principles of continuous integration (for example, version control and build automation---but no longer with SCCS or shell scripts!) and we've been running a self-hosted and self-maintained manager for automatic builds since the early 2000s. But we began to find the system showing its age and straining at the seams. The build manager uses dumb
ssh-ing to launch each build on a slave, so there is no communication channel between a build and the driver. The build indexer has become quite unmaintainable and is, shall we say, rustic: it resembles a web page from 1995.
We don't have the resources to pump any significant improvements into these systems, so a couple of years ago we had a look around for replacements.
Buildbot is nice. We liked the visualizations it comes with out of the box, and some of us know Python so we felt confident we'd be able to set up the software. There's no way of configuring by a GUI though, which restricts for us the audience of potential maintainers.
Hudson seemed too Java focused to fit easily into our model.