Is it hard to use fsc? Fsc should fix those compile times, especially for minimal changes. In the paper it reduced compile time to 25-33% of scalac's compile time. (13.9s to 3.8s and 11.3s to 3.5s)

I'll check it out; thanks for the tip!

nobody uses the Scala compiler that way. It is common to use FSC or the Simple Build Tool to compile incrementally

I was talking about incremental compiles (one loop around sbt ~test-compile), on a laptop, with a web browser open. Colleagues have benchmarked SSD compiles at 5x+ faster.