>Dbuild does set-version: "0.13.0-on-"${globals.scala-version}"-for-IDE-SNAPSHOT" for sbt.
>Where is globals.scala-version set? It looks like it reads it from the SCALAVERSION env variable.

It's set two lines above to `$SCALAVERSION-$SCALAHASH-SNAPSHOT`.

> I think duplication is the lesser evil compared to indirection, which makes it very hard to understand what's going on.

It's a tough call, but I'd still prefer to avoid repeating constants. It's so easy to get out of sync.