How to show the Scala version SBT is using

SBT FAQ: How do I show the Scala version that SBT is using?

Short answer: Issue the scalaVersion command at the SBT prompt.

Longer answer: I was having a problem getting a certain Scala feature to work when I compiled my code with SBT, and even though I knew I had set the Scala version in my build.sbt file, I wanted a way to double-check that SBT was indeed using that Scala version. That’s when I found I can issue the scalaVersion at the SBT prompt.scalaVersion