anchor.diff:  * https://github.com/tcrayford/values
   * https://github.com/solnic/virtus
   * https://github.com/rouge-lang/rouge[Ruby + Clojure = Rouge]
  +* http://blog.rubybestpractices.com/posts/rklemme/017-Struct.html[Structs inside out]
   
   
   === Enums in Ruby
  
positive.code: * https://github.com/nesquena/backburner[Simple and reliable beanstalkd job queue for ruby]
  * https://github.com/iron-io/delayed_job_ironmq[IronMQ backend for delayed_job]
  * http://www.iron.io/[IronMQ is the Message Queue for the Cloud], see http://www.iron.io/mq[comparison chart]
  
negative.code: == Ruby DDD Sample App
  
  Details here about other sample apps. Things that are unique to this implementation.
  
  Maybe (if I have time) could implement app in Rails using ActiveRecord with Mongoid, and then using repositories with Curator (and maybe Sinatra?). I wonder which one will be harder?
  
  By Paul Rayner
  
  == Implementation TODOs
  
  * Persist aggregates using Curator & MongoDB
  * Add couple of unit tests for key domain model objects - these seem kinda obtuse actually. I think I preferred the ones in the 1.1(?) master branch of the Java sample app
  * Populate some sample handling events
  * Update aggregates using async mechanism (using EventMachine?)
  ** `CargoWasHandledEventHandler`
  