An extension to sbt-crossproject SBT plugin, that allows you to cross-build for different scala versions.

The sbt-crossproject plugin allows you to cross-build for different platforms, such as JVM, Scala.js or Scala Native. This plugin allows you to treat a particular scala versions as a platform, so you can cross-build for "Scala 2.11 on JVM" and "Scala 2.12 on JVM".

SBT already has a built-in support for cross-compiling for multiple Scala versions, but it stays aside from the regular tasks evaluation. With sbt-scala-crossproject builds for different scala version are treated as a separate SBT modules. This makes it possible to:

• Build them in parallel,
• Have different set of supported scala version for different submodules.

// Some library code cross-built for 2.11 and 2.12
lazy val lib =
  crossProject(ScalaPlatform("2.11"), ScalaPlatform("2.12"))
    .crossType(CrossType.Pure)
    .settings(/* ... */)
    .scalaSettings("2.11")(scalaVersion := "2.11.12")
    .scalaSettings("2.12")(scalaVersion := "2.12.4")

lazy val `lib-2.11` = lib.scala("2.11")    
lazy val `lib-2.12` = lib.scala("2.12")

// Apache Spark application built for 2.11 only
lazy val sparkApp =
  crossProject(ScalaPlatform("2.11"))
    .crossType(CrossType.Pure)
    .dependsOn(lib)
    .settings(/* ... */)
    .scalaSettings("2.11")(scalaVersion := "2.11.12")

lazy val `spark-app-2.11` = sparkApp.scala("2.11")

You can also look at the plugin tests.

Add the following line to your project/plugins.sbt:

addSbtPlugin("com.timushev.sbt" % "sbt-scala-crossproject" % "0.1.1")

Choose one of versions available on BinTray or the latest one. Then add the following line to your project/plugins.sbt:

resolvers += Resolver.bintrayIvyRepo("rtimush", "sbt-plugin-snapshots")
addSbtPlugin("com.timushev.sbt" % "sbt-scala-crossproject" % "x.x.x-y+gzzzzzzz")

Note, that snapshots are not updated automatically.