cuid2 VS ksuid

The CUID readme [1] explains that there's no real point to K-sortable on modern hardware:

[1] https://github.com/paralleldrive/cuid2?tab=readme-ov-file#no...

There's a comparison in the README of the project:

https://github.com/paralleldrive/cuid2#the-contenders

Some of the arguments mentioned are explained elsewhere in the README, others are assumed.

One argument standing out for me is the lack of collision-resistance for UUIDv4 which is surprising for me and I didn't spot any sources for that argument.

Another argument is the entropy source where they go about that Math.random is not reliable as a single entropy source but glimpsing at the source code, they sprinkle the CUID with Math.random data.

I am no expert in ID security, so I am not qualified to speak about the validity of their arguments, only that there's insufficient information to validate without prior knowledge about the problem domain.

I'm recently finding cuid2 to be the best of these alternative GUIDs. They seem to have all of the benefits for what you would want to use a GUID for, but none of the drawbacks of existing implementations.[1]

[1]: https://github.com/paralleldrive/cuid2#the-contenders

I've just released v2.0.0 of my cuid2 python port. The original cuid2 package comes from JS world by ParallelDrive. They have a lot of the reasons to use Cuid2 posted in their repo, including

I recently wrote a Go implementation of CUID2 because I could not find an existing one. It is not hello-world, but it is not duff's device either, which by the way neither could explain what it did from just the raw code in isolation.

I think this implementation is the original one. It has the following to say about why it exists. And what it is good for:

There's also https://github.com/paralleldrive/cuid2 which likely should be added to this as it is likely one of the better ones out there now.

If you're using prisma then you can use CUID or CUID2 to manually generate it.

OP here - we avoid sequences in all but one part of our application due to a dependency. We use [KSUIDs][1] and UUID v4 in various places. This one "gotcha" applies to any sequence, so it's worth calling out as general advice when running a migration like this.

[1]: https://segment.com/blog/a-brief-history-of-the-uuid/

UUID v4 isn't large enough to prevent collisions, that is why segment.io created https://github.com/segmentio/ksuid which is 160bit vs the 128bit of a UUIDv4.

Assuming you don't need to use UUIDv7 (or any UUID's) then https://github.com/segmentio/ksuid provides a much bigger keyspace. You could just append a string prefix if you wanted to namespace, but the chance of collisions of a KSUID is many times smaller than a UUID of any version.

KSUID's are have temporal-lexicographical order plus 128 bits of entropy, which is more than UUIDv4.

https://github.com/segmentio/ksuid

That's why you use ksuid (https://segment.com/blog/a-brief-history-of-the-uuid/) or, if you're willing to go with a draft spec you could go with the new UUID formats https://www.ietf.org/archive/id/draft-ietf-uuidrev-rfc4122bi...

Interesting in more history of UUIDs? Twilio Segment's blog has an amazing history lesson about how they came to be.

I use the ksuid from segment. https://github.com/segmentio/ksuid