What is functional programming? What is reactive programming? Taken together, these two programming practice can help break the cycle of unmaintainable spaghetti code in large applications by producing predictable, testable, composable code. In this talk, we’ll cover the fundamentals of functional and reactive programming in JavaScript. We’ll look the reactive extensions project (RxJS), as well as Redux, and see how these can be utilized to manage complex intereactions and produce predicatable systems. We’ll also look at how these practices can be used to make life easier in major front end frameworks, including Angular 2, React, and Vue.