just making things clear:
Oban is a background job tool, it uses db to manage jobs, but to keep it performant and in a healthy state the data on jobs needs to be ephemeral, at some point in time you gonna delete the data of jobs already executed(with success or failure).
Kafka on the other hand is an event store, built do deal with massive amount of events.
It’s good to remind that ETS is an in memory key value store and GenServer is an abstraction of a processing worker.
Just given the nature of those tools any multi-services event source/event store solutions would never be possible with only oban, ets and genservers. But I personally would avoid this type of thinking, at least to what comes to engineering solutions, it’s better to start with a problem and think of multiple ways to get to what needs to be done.
