Why does 0.13.6 download Scala 2.10.4 by default?

Question

Why SBT 0.13.6 is downloading Scala 2.10.4 by default?
Even if in C:\Program Files (x86)\sbt\conf\sbtopts it is written Scala version (default: latest release) which seems to not be true.

C:\Users\Joan>sbt scala-version
Getting org.fusesource.jansi jansi 1.11 ...
:: retrieving :: org.scala-sbt#boot-jansi
        confs: [default]
        1 artifacts copied, 0 already retrieved (111kB/15ms)
Getting org.scala-sbt sbt 0.13.6 ...
:: retrieving :: org.scala-sbt#boot-app
        confs: [default]
        44 artifacts copied, 0 already retrieved (13750kB/563ms)
Getting Scala 2.10.4 (for sbt)...
:: retrieving :: org.scala-sbt#boot-scala
        confs: [default]
        5 artifacts copied, 0 already retrieved (24459kB/375ms)
[info] Set current project to joan (in build file:/C:/Users/Joan/)
[info] 2.10.4

Cheers

Answer 1

Because sbt is built on scala 2.10.4, as you can easily verify here.

In your own project, simply specify the scala version you indend to use in the same way sbt does, i.e. providing the scalaVersion build setting.

It's generally speaking a good idea not to depend on a default.