Event sourcing is a design pattern to build applications that are domain centric and easy to extend. The pattern is based on the usage of a persistent event log which substitutes the more classical relational database model for Rails applications.
Such event log can then be used for extending your application in all sort of creative ways. For example, by synchronizing data between your microservices, trigger side effects without cluttering your models or controllers, or build data views optimized for your query needs. In this talk, I'll present the basic ideas, some of the tradeoffs and challenges you might find and how you could start experimenting with it.