Hello, Android! It's Mirah!
This was the first proof-of-concept Android application created using the Mirah programming language (then known as Duby). It's left here for historical reasons, but if you are interested in writing Mirah Android applications you would be better served by Pindah (tools) and Garrett (an example app).
Install the Android SDK, an Android platform version, and JRuby. Then get Mirah:
$ jruby -S gem install mirah
Copy local.properties.example to local.properties and edit it to point to your SDK. If you're not targeting Android 2.1, you might need to edit default.properties too.
Then you should be set to do "ant debug", and an apk file should be generated in the bin/ directory.