When I use removeItem state operator then TypeScript complains that message object can be possibly undefined even though I specified the type for removeItem operator. I could fix the issue with optional chaining but that is not possible if I want to use a utility library like Ramda

![image](https://user-images.githubusercontent.com/14946081/104027016-135aed80-51c7-11eb-9316-9b3dbf5b79bf

For an implementation of #126 (PostgreSQL driver with SKIP LOCKED), I create a SQL table for each consumer group containing the offsets ready to be consumed. The name for these tables is build by concatenating some prefix, the name of the topic and the name of the consumer group. In some of the test cases in the test suite, UUID are used for both, the topic and the consumer group. Each UUID has

I would like to review the docs and explain also de concepts behind some decisions.
Things needed to explain:

• DDD objectives and reasons why.
• Core concepts like
  • bounded context
  • anti corruption layer
  • domain
  • value objects VS entities
  • aggregates
  • aggregate root
  • layered architecture and each one responsibility
  • reasons for the command and query bus
  • the even