Injecting custom code into authentication and authorization in ASP.NET has always been a chore. ASP.NET Identity is a library built to replace both ASP.NET Membership and Simple Membership, making it much easier to implement custom authentication and authorization without the need to rewrite core components. In this session I will go deep into the abstractions that ASP.NET Identity builds atop of, and show how to take advantage of these hook points to implement a custom membership system.