tl;dr; you should really remove any remaining useCoursier := false from your build.sbt’s

sbt users beware: when sbt changed it’s default dependency manager from ivy to coursier, it had a few bugs, causing some users (like us) to switch back to ivy.

After a long bisecting session in a rather large build I noticed that this was the root issue to our very slow sbt startup and ‘import into Intellij’ times. Simply removing useCoursier := false from the build.sbt reduced the time to import the project into Intellij from 2:45mins down to 35s. That was somewhat surprising because I timed the bare import, without any fetching of dependencies…

These days the regular sbt / coursier combo is very mature, coursier is much better than ivy, so you really should not use ivy any longer.