Scala, Typesafe, SBT, IntelliJ IDEA, Specs2, Play, Tests ...

Scala has a great ecosystem evolving from developers needs. 

Everything is not "IDE integrated", but I kind of hope that it will stay this way. I don't like menus that fill up the screen.

As a reminder, here is the path I followed:

1. Go to Typesafe:
   1. Download Scala (the "Typesafe Stack").
   2. Play with the REPL (the console)
   3. Read the free e-book
2. Download SBT, if not already done
   1. Create a project (you just have to follow the quick start)
   2. Configure the SBT project to use the sbt-idea plugin
   3. Run gen-idea to create the IDEA project files.
3. Launch IntelliJ IDEA 
   1. Get the plugins: Scala (and optionnaly SBT, it will only display the SBT console in IntelliJ.)
   2. Open the created SBT project
4. You are already TypeSafe, go to Test or Spec safety also
   1. There is no one true path like JUnit here, you will have to choose
   2. SBT integrates with 3 main players.
   3. I choose to go with Spec². Simply configure SBT to use it.
5. As for the Web frameworks, Lift and Play are kind of associated with Scala
   1. I choose Play 2.0. It is very early and lacking functinonality ! Depending on what you want to do, Play 1 has a more mature Scala Module.

So it is not obvious, but nicely incremental. The starting points are SBT and REPL. From here you choose a IDE and a testing framework.

The rest really depends on your specific needs.