View Source Authorization
Ash Policy Authorizer
Generally speaking, you will want to use
Ash.Policy.Authorizer to authorize access to your resources.
At one point, it was a separate package but it is now built directly into Ash.
For usage, see the policies guide.
Implementing a custom authorizer
Implementing a custom authorizer is pretty complex. Instead of writing a guide, it would be best to just have some discussions if/when someone thinks that they need one. Make an issue and we'll talk it over.