That's not really buildbot's fault. You have a lot of control on how your project builds. Our build system created a chroot each time it went to build - so tha

That's not really buildbot's fault. You have a lot of control on how your project builds. Our build system created a chroot each time it went to build - so that got us the clean environment we needed. Buildbot had no effect on that, it just ran the build script. If you really wanted to you can have buildbot coldstart a machine from scratch - we coldstarted machines for testing, but it was definitely doable for building as well.