This article would delve deeper into the ASP.NET Core authorization system, specifically focusing on custom authorization handlers. While action filters and middleware provide a way to restrict API calls, authorization handlers offer a more structured and centralized approach for implementing complex authorization logic. The reader would learn how to define custom requirements (e.g., "MustBeOver18Requirement"), create handlers that evaluate those requirements based on the current context (e.g., user claims, resource being accessed), and integrate them into the authorization pipeline. This approach is particularly useful when restrictions become more intricate than simple age or blacklist checks, such as role-based access control, permission-based access control, or policy-based access control. Furthermore, it provides a cleaner separation of concerns compared to embedding authorization logic directly within action filters or middleware