For an example Hathora game that does client prediction and rollback, take a look at https://github.com/ourcade/flappy-bird-hathora

Thanks, that is a really interesting example.

I am a bit worried by "Dropped or lost input packets are also not handled in this example.", as I would have hoped handling dropped + lost packets would be a framework issue, not a "me" issue.

I'm not the author of the game so not sure exactly what they meant by that, but that game uses Websockets which are built on top of TCP, so developers shouldn't have to deal with dropped packets (and our UDP implementation will have automatic retry built in as well)

The trick is to always send previously unconfirmed inputs. That way if a packet is dropped the missing input is delivered in the next packet.