DDD – Does DDD + POCO Make Sense

To be honest, your question is not easy to understand.

When you start your DDD journey, you identify your domains and bounded contexts. Ideally you have one bounded context per domain but it depends. Each domain has its own domain model, you mention this yourself. But these domain models have nothing in common. They don't know about each other. Your idea to have one base class for two entities from different domains does not fit to DDD. Real domain models do not allow accessing anything within the domain model to anything outside of the bounded context. All communication between bounded contexts go via pre-defined interfaces like queries and commands if you do CQRS. This way you can make your components loosely coupled and allow different groups to work on different domains without depending on each other.

Bounded context always mean separate application. You can think of a separate solution though. It will include a domain project with entities, VOs, commands. It will also include services project with command handlers and query handlers. It will include transport projects like an application that uses service bus for commands and events.

Remember that using domainevents is crucial to enable inversion of control on the business logic level, when one domain informs everyone else about things that happen, allowing the, to react accordingly and do necessary activities. You can think of order payment event in sales domain that triggers a dispatching process in the inventory domain. Sales domain does not even need to know about the inventory domain.

If there is little behavior a DDD approach can be overkill, its your application its totally data-centric and with little logic probably the coupled solution can be a good decision. I don't know what technology are you planning to use, for a system like that i probably choose a framework like rails, grails or django an use ActiveRecord pattern.

The worst with this coupled systems is when you ends up unconsciously with a system like that, but if your take a conscious decisions based in your knowledge about the problem, things like DDD or ORM's are only tools in your toolbox and you pick up the right one for the project at hand.