CQRS - Design Pattern
References
https://martinfowler.com/bliki/CQRS.html
https://docs.microsoft.com/en-us/azure/architecture/patterns/cqrs
Greg Young:
https://leanpub.com/esversioning/read
https://www.confluent.io/blog/event-sourcing-cqrs-stream-processing-apache-kafka-whats-connection/