Dynamic languages on Google App Engine - an overview. Ola Bini’s notes on exploring the new Java support for App Engine with the aim of getting JVM dynamic languages such as JRuby running. Restrictions include a complete lack of threads (which will make it hard to get Scala up and running), but JRuby trunk now works without modification.
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Scala runs fine on app engine. Only the actors library might present difficulties, which can be a problem for the Lift Web Framework as it relies heavly on actors. They are working on it, though.