Tag Archives for " aggregate-root "

Business Rules – When to Break Them

The nice thing about programming is that everything is black and white.


When designing new features, we all go through a process of discovering requirements. If you are a good developer, you will start to ask questions and probe deeper to find the edge cases. Why? Because you know the edge cases can often take up 80% of the development time. But is that where 80% of the value is?Continue reading

4 Secrets to Inter-Aggregate Communication in an Event Sourced System

Ok, so you have two event sourced aggregate roots. You need to call a method in one from the other. How do you do it?

If you find your self asking this question, don’t worry, your not alone. It comes up a lot.

The short answer – it suggests there could be something wrong with your aggregate root (AR) boundaries.Continue reading

Aggregate Root - How to Build One for CQRS and Event Sourcing

Aggregate Root – How to Build One for CQRS and Event Sourcing

An aggregate root is at the heart of your domain. I am going to dissect a simple implementation of an Aggregate Root and reveal how it works in a CQRS and Event Sourced system. Before we dive in, we need to fly through some terms often used in DDD.Continue reading