[YZF]

Usually when you're ingesting something into Kafka it's important to know whether that was successful or not, hence the more or less inherent request/response that's part of that. That said it's an interesting thought experiment to see how far you can go without that.

When I think of large scale success stories around the request/response model I think AWS (where famously Bezos mandated APIs first) and Google. Both now have services that look more event oriented (e.g. SQS or Firebase). And ofcourse the modern web (though the ugly hacks needed to make something look like event driven was certainly not fun).

Events related to data changes are about keeping data structures in sync via events. Also known as state-based architecture. Something I worked on in the early 2000's kept a remote client/UI in sync with the server and a database using events like that and was a pretty lean/neat implementation.

Good one on the Chrome re-making requests when you're online for an active tab. That's certainly an interesting use case.

My intuition is that some things are very naturally events. Let's say a packet arriving into your computer. A mouse click. And some things are naturally a request-response. Let's say calculating the Cosine of an angle. You can replace x = sin(y) with an event, and an event that comes back, but that feels awkward as a human. Maybe not the best example...

It's another variation on the sync vs. async debates I guess. Coroutines or callbacks...