Comment by orefalo

I wrote an article comparing different GUID implementations and also prepared a clear spreadsheet with side‑by‑side implementation comparisons.

https://medium.com/@orefalo_66733/globally-unique-identifier...

Looking at your implementation, I like the clean split between shard, tenant, and sequence.

However, this results in a 160‑bit format, which does not fit natively in most databases, as they usually use the UUID type. I also find 60 bits of randomness to be low (ULID also uses 60).

Last point, using a GUID is not only for sharding. It is also important for protecting against predictability, which beyond the GUID structure, requires using the right approved crypto‑safe random generator.