Our codebase is a few years old so we are using maven for our builds instead of SBT. I've been using the intellij incremental compiler and it seems to work well. Once in a while it will complain so I hit the reimport button on maven and then its fine. There is no code in our codebase that maven compiles but Intellij can't. I do remember using spray.io and Intellij had a hard time with that library but recently the problem has gone away.
