how to configure SBT to pick the desired scala version (2.9)

While creating a project with sbt command it always prompt开发者_开发技巧s for the 2.7.X version of scala however I have 2.9.0 and sbt 0.7.7 installed is there a way to configure sbt to pick 2.9 by default.

If you use sbt version 0.10 instead it has changed a bit, in the build.sbt file you specify scalaVersion := "2.9.0-1" (default seem to be 2.8.1)

See Migrating from SBT 0.7.x to 0.10.x or Quick Configuration Examples. The Full configuration example shows Scala style configuration.

Threre is a ~/.sbt/plugins/ library where you store global plugins. But I do not yet know if you can define a global build properties.

In your project directory there should be a file called build.properties. There you can configure SBT to use whatever version you want. When you change the file either exit SBT or use the command reload.