I'm not sure why crypto exchanges have such lousy technology. Lost acks, weird parser errors, missing order id fields, sessions giving no indication that the matching engine is down, etc.

It seems like any conceivable way an exchange can break will be encountered after only a couple months of trading. It's a complete shit show compared to traditional exchanges

Sounds like tuesday to me. One thing you learn about exchanges (I mean all of them as a software category) is that you can’t trust: documentation, reasonable expectations, the experience you’ve got last week, the idea that all symbols behave similarly, reproducibility on test servers and vice versa, to name a few. Don’t rely on these and you’ll be relatively safe.

But really, expecting a deterministic confirmation is a rookie mistake. Exchanges feel very asynchronous after a short while and the intuition should tell you that that a confirmation is just “ok, I hear ya”, not “effective immediately we’ll suspend our queues and reschedule trades to fulfill your urgent request”. The temporal uncertainty of order status is a quite common phenomenon, ime.