Prettier : Prettier is an opinionated code formatter. It enforces a consistent style by parsing your code and re-printing it with its own rules that take the max...
Lerna : A tool for managing JavaScript projects with multiple packages.
tracing-framework : Rich tools for instrumenting, analyzing, and visualizing web apps.
PhantomJS : PhantomJS is a headless WebKit with JavaScript API. It has fast and native support for various web standards: DOM handling, CSS selector, JSON, Canvas...
Beautify, unpack or deobfuscate JavaScript and HTML, make JSON/JSONP readable, etc.