[themafia]

What problem does leaking the timestamp cause?

UUIDv8 gives you timestamp + counter + random.

The advantage is that lexical order and chronological order are the same and you still retain enough random bits that guessing the next generated timestamp is not easy.

[michelpp]

uuidv8 does not contain a timestamp or counter unless you put them in there, it only contains a version and variant field. It's a very broad format that lets you contain whatever bits you want.

This library converts a uuidv7 into a cryptographically random but deterministic uuidv4 recoverable with a shared key. For all intents and purposes the external view is a uuidv4, the internal representation is a v7, which has better index block locality and orderability.