Reconciling externalized authz with search is actually quite a challenging problem. For standard externalized authz, the recommendation is some form of pre-filtering or post-filtering [1], for which we actually built LookupResources (pre-filtering) and CheckBulkPermission (post-filtering) into SpiceDB.

However, as you mentioned, life is easier when the main database can handle everything, so we actually built a solution in that space called Materialize [2], which heavily denormalizes the authorization data and allows for joining within application databases such as Postgres. My colleague Evan actually put together a really cool video about using it with Gitea [3].

Recognizing that even with Materialize, however, the need to consume events can be a bit annoying, I've been doing some work to allow Postgres itself to do native JOINs against SpiceDB (and other operations). I demo it briefly in our recent announcements video [4] and I think it effectively solves this problem within Postgres, while still allowing for all the benefits (scale, performance, redundancy, distribution) of externalized authz.

[1]: https://authzed.com/docs/spicedb/modeling/protecting-a-list-...

[2]: https://authzed.com/products/authzed-materialize

[3]: https://www.youtube.com/live/u3i1SEd9Ll8?si=mCz5mZterxthoEwj

[4]: https://www.youtube.com/live/uz_gxz3whS0?si=g4NUZAIltYVyFzYj...

Disclaimer: I'm cofounder and CTO at AuthZed and we build SpiceDB and Materialize