is Microsoft ASP.NET WebHooks a viable way for building a plugin architecture?

Question

i am designing an architecture for third parties to be able to add and extend functionalities to my ASP.NET MVC web application though plugins. I am thinking of using Microsoft ASP.NET WebHooks as a mechanism of integrating the functionalities of the plugins to my app app using asynchronous callbacks and hooks. The Application is a payment gateway and i need third party developers to add more features to the app. Is it a viable architecture, and what are the alternatives for building such a plugin architecture.