Yapura, is a DSL for specifying object models and services. With a single definition file, generators will create code in your language, complete with proper serialization of datatypes.
Install it with:
$ gem install yapura
To test it out, run
$ yapura examples/simple_definition.rb ruby
to see ruby code dumped to your console. Pipe it to a file to save it.
We need more types and more languages!