Ramda is a JavaScript library that helps you write functional, concise and reusable code. Ramda focuses on immutability and side-effect free functions.
Lazy.js is a functional utility library for JavaScript, similar to Underscore and Lodash, but with a lazy engine under the hood that strives to do as little work as possible while being as flexible as possible.
Ramda is a practical functional library for JavaScript programmers.
Features
Ramda emphasizes a purer functional style. Immutability and side-effect free functions are at the heart of its design philosophy. This can help you get the job done with simple, elegant code.