In my previous post on parallelising tests in SBT, it doesn't work well in practice or, at least, on CircleCI. The main disadvantage is that it doesn't balance the tests by their run time. Balancing tests by their run time would reduce the total time significantly.

SBT, the official build tool for Scala, is a very complex build tool. It's one of those things that makes me wonder if I am stupid or the tool's complexity surpasses average human intelligence. I've done a few things with SBT (e.g. printing