Creating ABAC functionality for an existing application

[vivid apex]

I'm working on a project which has a account packages system for different roles types. Because of this instead of using an RBAC approach I decided to go for an ABAC approach as I thought it'd be easier enabling/disabling specific permissions based on their package level and other parameters.

Are there any existing tutorials that I can use to help guide me?
So far I've done some research but I'm not getting a whole lot of in depth tutorials/examples etc which show how to do a more advanced ABAC system.

Currently the best one I've found is in the link below:
https://github.com/rubenjgarcia/nestjs-abac-app/tree/main

Any other suggestions?

[kindred nova]

You can check out this library called CASL, Nest’s docs on authorisation also mention CASL and provide an example integration.