Re: Large domain, small team: how many contexts?

Hi Tom, 

 "duplicate entities" does not sound welll... There are of course many definitions for what an Entity is, one is "A thing with distinct and independent existence", another is "An object that is not defined by its attributes, but rather by a thread of continuity and its identity". In our software-world an entity is a representation of a real-world thing with a very specific characteristic: given its id, you can point it out and there cannot be any doubt which instance is addressed by this id. In DDD, a certain entity can appear in different forms (views) in different Bounded Contexts but in the end, all of these point to the same thing. The different views will very likely have a common base-set of attributes. This pleads for a common model to handle the base-views entities. Extending these classes in the various BC's is a way of implementing, interesting thougths are in the DCI (Data, Context & Interaction) vision: Data, context and interaction - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Data,_context_and_interaction
 In DCI, behaviour is captured in roles. Entities may implement various roles, roles will have a more strict binding to specific BC's than the entities themselves. E.g. a Person entity will appear in many BC's, but as an Employee in the HRM BC, as a user in the System BC, as a plannable resource in the Planning BC etc.
 

 Best, Rob.