sbt 0.13.1 multi-project module not found when I change the sbt default scala library to scala 2.11.2 -

i use sbt 0.13.1 create 2 modules, , create project/mybuild.scala compile 2 modules. mybuild.scala:

import sbt._ import keys._ object mybuild extends build {     lazy val task = project.in(file("task"))     lazy val root = project.in(file(".")) aggregate(task) dependson task } 

when change scala library 2.11.2 set scalahome. go maven download task.jar , failed, that's strange. sbt bug?

there github test project address: test-sbt-0.13.1

i'd recommend move sources of root project root subfolder (task2), , add them aggregated. remove aggregating , depending on same project:

object mybuild extends build {           lazy val task = project.in(file("task"))           lazy val task2 = project.in(file("task2")) dependson task           lazy val root = project.in(file(".")) aggregate(task, task2)  } 

this works me, it's strange such non-standard project structure works fine default scalahome. seems problem in way in sbt resolves such dependency external.

p.s. answer doesn't cover whole story. see @jjst's answer clarify more.