I understand that it's a lot to digest but a comprehensive example application can only help demonstrating how to use a particular toolkit/framework. For a better understanding of the basics of log-centric, event-driven architectures I recommend reading The Log: What every software engineer should know about real-time data's unifying abstraction
by Jay Kreps. It also has a good link collection for further reading at the end. I also find it very important to have a good understanding of distributed systems basics. Distributed systems theory for the distributed systems engineer
is a nice collection of introductory literature. A book I can really recommend is ntroduction to Reliable and Secure Distributed Programming
. Also important in this context is an understanding of Domain Driven Design. Domain Driven Design Distilled
is a good starting point here. Hope that helps.