Archive Monthly Archives: November 2014

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

Is a 100% Provable Audit Log Possible? – Hint, with Event Sourcing it Is and I’ll Show You How

If you’ve been developing for any length of time you’ve probably had to create an audit log. Here’s the question though, are any of these logs, a 100% provable audit of all changes in the system? I’m guessing not. With event sourcing, a 100% provable event log just happens to be a handy by product. So how does it work and how can you implement it?

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