Google has released App Engine support for Java … Great: JRuby + Rails can be used on the infrastructure!

JRuby on Google AppEngine: First Impressions [Article by Nick Sieger]

In the end, I’m still extremely excited about the prospect of using JRuby and Rails on AppEngine, and can’t wait to see what people build with these tools. If you want a little head start, you can check out the first Rails application I deployed, jruby-rack.appspot.com

JRuby on Rails on Google App Engine [Article by Ola Bini]

In this post I thought I’d go through the steps you need to take to get a JRuby on Rails application working on GAE/J, and also what kind of characteristics you should expect from your application.

trade-offs and constraints:

• No regular net/http, restclient, ActiveResource usage.
• No ActiveRecord! (use Bumble !?)
• 1000-files limit per application! (freeze rails gems remove unused stuff!)
• Startup/first request processing is slow.
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