Too Long; Didn't Read
TypeScript now supports the concept of a mixin - a function that can take a class, extend it with some functionality, and then return the new class, allowing other classes to extend from it. Mixins allow classes to mix and share functionalities. The concept is fairly uncomplicated - if we are familiar with inheritance, higher-order classes/functions and their syntax, we can jump right into them. In a sense, this allows for multiple inheritance - if some of our classes are only needed to share functionality, then we can write it inside a function so it can be mixed with other classes.