This was a lovely piece. I'm only surprised by paucity of interesting comments here. If Joran or anybody sees this late comment: I'd appreciate any other references to the approach. Surely it wasn't invented by TigerBeetle?
A wonderful paper that I highly recommend is A Transaction Model from Jim Gray, that illustrates like no other than transactions are all about coordinating actions and when to externalize their results to a user. The mental model presented in this paper frequently informs my thinking when designing systems
https://jimgray.azurewebsites.net/papers/a%20transaction%20m...