Gather all dependencies jar and generate start script for running, all placed in `target/` dir

Build.scala

  lazy val copyDependencies = TaskKey[Unit]("gather-lib")

  def gatherDeps = copyDependencies <<= (update, crossTarget, scalaVersion, internalDependencyClasspath in Compile, mainClass in Runtime) map {
    (updateReport, out, scalaVer, deps, main_class) =>
      var projDeps = Array[String]()
      deps.foreach {
        depsDir =>
          val x = depsDir.data.getCanonicalPath.split("/")
          if (x.length > 3){
            val projName = x(x.length - 3)
            println("Copying `" + out / "lib" / projName + "`...")
            IO.copyDirectory(depsDir.data, out / "lib" / projName)
            projDeps :+= "lib/" + projName
          }
      }
      updateReport.allFiles foreach {
        srcPath =>
          val destPath = out / "lib" / srcPath.getName
          println("Copying `" + destPath + "`...")
          IO.copyFile(srcPath, destPath, preserveLastModified = true)
      }
      // generate executable script start.sh
      println("Generating start.sh...")
      val shScript =
        """#!/usr/bin/env sh
          |java "$@" -cp "classes:lib/*:%s" %s
        """.stripMargin.format(projDeps.reduce(_ + ":" + _), main_class.getOrElse("xxx")).trim + "\n"
      IO.write(out / "start.sh", shScript.getBytes)
  }

Add to your project settings:

.settings(gatherDeps)

From sbt console type:

gather-lib