TechDays 2017 - Michiel Overeem - Event Sourcing after Launch

Event sourcing can be a solution for certain problems in your application, but it also comes with its own set of challenges. One of those is the evolution of your event schema. How should you handle changes to events? We found many approaches while doing our research (we’ve published earlier results in our paper “The Dark Side of Event Sourcing”) and we gained a lot of experienced from building a full-size ERP application using CQRS and event sourcing. In this talk we will show what kind of approaches we’ve found and what we use to deal with our specific challenges. We will also share early research results from our interviews with over 20 different companies using event sourcing. Every request for advice can be answered with ‘it depends’, and this talk will not solve that. But we will tell you what your options are, what we think works, and what many others have done.