Unshackle Your Domain - Explicit State Transition Models

Greg Young has some very interesting ideas surrounding explicit state transition models. The end result is a system that can be rewound and fast forwarded and that doesn't use a database in a traditional way.

In fact he recommends an in-memory current state, while past state snapshots and the complete history of state transitions written to disk.

It is interesting how he started with a domain problem and the end result lead him to a NoSQL type system with a denormalized reporting database.

I think his idea of every select is a report really simplifies the way an ORM is used. Instead of worrying about lazy vs eager loading of child objects, you create a de-normalized flat reporting object that represents all the data you need for that specific report ( ie. UI Element).