WP Rocket - WP Rocket offers a caching plugin for Wordpress.
ExpressJS - Sinatra inspired web development framework for node.js -- insanely fast, flexible, and simple
Yoast - Yoast offers plugins to improve SEO and optimize web sites and blogs.
Chart.js - Easy, object oriented client side graphs for designers and developers.
Wordfence - Comprehensive security plugin for WordPress.
Famous Engine - The Famous Engine is a free and open source JavaScript rendering engine.