Stephen Zoio on "Event sourcing with CQRS and Free Monad"

In this talk Stephen Zoio will introduce the “event sourcing with CQRS” pattern, and investigate how to implement in a Scala application using free monads. The main objective is to develop a generic and reusable mechanism in which there is a separation of concerns, with event logging split from the domain logic. We develop this pattern in an abstract way. We then specialise it to an implementation that logs events to a Sql database, and then uses CDC to propagate events to a Kafka cluster. Validation, state updates and events logging all happen in an atomic transaction, with the transaction management performed behind the scenes by the framework. This approach is well suited to handling complex domain-wide validation requirements, yet still preserving concurrency.

Arrive from 5:45pm for pizza and conversation. Talks start at 6:30pm. As always, newcomers most welcome.

Hope to see you there,
-Luke