In the case of Authzed, we provide a gRPC API [0] which can be used from any application or language that supports gRPC, as well as designed client libraries for specific languages [1] to make integration even easier.
Applications primarily integrate by making Check requests [2] at any point in which a protected resource is being accessed and Write requests [3] at any point in which permissions are granted or removed.
In the case of Authzed, we provide a gRPC API [0] which can be used from any application or language that supports gRPC, as well as designed client libraries for specific languages [1] to make integration even easier.
Applications primarily integrate by making Check requests [2] at any point in which a protected resource is being accessed and Write requests [3] at any point in which permissions are granted or removed.
Source: I am the third cofounder at https://authzed.com :)
[0]: https://docs.authzed.com/api/overview
[1]: https://docs.authzed.com/lang/lib-index
[2]: https://docs.authzed.com/api/check
[3]: https://docs.authzed.com/api/write