Oh what a huge article and a good read. Thank you. Ok, let's go.

Why people use Kafka? Because you can throw lava at it and it will eat it.

RabbitMQ is also very good, don't have production experience on it, so I leave it for a specialist. Redis (or valkey.io) is also amazing and very fast.

But for a tram system or any system that needs persistent record for a period of time, I use a Kafka cluster with minimum of 3 servers. I might need to save that data for days or weeks or a single day. Most of the time the connectors will bring that data, some streams transform it and put it back to Kafka and somewhere down the road, a Postgres connector will save that out. And Kafka works very well on a cluster. For what I've seen it is pretty much limited by network bandwith. It is not that hard to configure even with TLS. Documentation is amazing and you know that you get a rock solid system.