UUIDv7's timestamp can race arbitrarily far ahead of the clock

UUIDv7 doesn't have the properties you think it does

UUIDv7 is widely sold on monotonic ordering, an embedded creation timestamp, and unguessable IDs — but the RFC guarantees none of these strictly. Implementations may alter the timestamp, and Python's uuid7() can drift unboundedly into the future after a backward clock jump under load. Ordering across nodes was proven impossible back in the 1970s. Only uniqueness and collision resistance hold reliably, so vet any implementation before trusting its extra properties.

Timestamps are only time-ordered if you know what time it is and you don't know what time it is.

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2026-10-23