- Ory came out first with Ory Keto ( https://github.com/ory/keto ) which is trying to be a close adaptation of the paper. Initially, many concepts were missing but they are making a lot of progress with the DSL and it interfaces with the rest of Ory (OAuth2, User Mangement)
- Authzed came out as a SaaS only, open sorucing the code base later on at https://github.com/authzed/spicedb
- Auth0 has been playing around with Zanzibar concepts in various forms and published a beta service at https://dashboard.fga.dev - apparently now also open source parts of it similar to what Authzed did: https://github.com/openfga
- Permify - who on a side note spammed me quite a lot with outreach because I was active in these communities - joins as well https://github.com/Permify/permify
It's exciting to see so much movement, yet also sad that so many companies are brewing their own beer instead of working collaborative on the more succesful projects. Feels like we'll just end up with one or two successful projects (looking at Ory / Auth0 here) with the rest perishing. I'm wondering if there truly is a business model for just this permission system as a saas service (looks like this is what everyone is going with). Here I'm giving Auth0 probably the biggest plus as they have an established identity service. Then again, Okta (parent of Auth0) and Auth0 themselves are not particularly known for good business practices that we usually expect from developer tooling.
What's refreshing though with Permify is that they are trying a bit of a different approach to Zanzibar!