UUIDs leak information, by definition. For that reason, I'm not a fan. It's just leaking on the other side. I'll explain: A UUID should be pretty unique in the

UUIDs leak information, by definition. For that reason, I'm not a fan. It's just leaking on the other side. I'll explain: A UUID should be pretty unique in the universe. Wherever it crops up, as there should always be an assumption of the possibility of leaking data and associated data at the same time, whomever the UUID belongs to has had their information leaked. That could be associated meta data in a request like IP address, to a print out that has a user's UUID in the header. In all cases it ties data to an individual. Better is to just use a high integer that doesn't simply increment, but changes by an amount. But low enough to blur into noise. Heck, this can be rotated. I stand to be convinced otherwise, but via the reasoning above I believe UUIDs are not desirable for user privacy.