Casper JS
Navigation scripting & testing utility for PhantomJS and SlimerJS
Spa Eye
Backbone debugger for Firefox
Rulers Guides.js
Creates Photoshop-like guides and rulers interface on a web page
Grunt
Grunt: The JavaScript Task Runner
Js Cover
JSCover is a tool that measures code coverage for JavaScript programs.
Blaver
A JavaScript library built on top of the Faker.JS library. It generates massive amounts of fake data in the browser and node.js.
Nightwatch
UI automated testing framework based on node.js and selenium webdriver
Qunit
An easy-to-use JavaScript Unit Testing framework.
Jasmine
DOM-less simple JavaScript testing framework
Jasmine Ajax
jasmine-ajax - A library for faking Ajax responses in your Jasmine suite.
Angular Debaser
Just a better way to test AngularJS apps.
Bower
A package manager for the web, created at Twitter
Trace Kit
Attempts to create stack traces for unhandled JavaScript exceptions in all major browsers.
Gulp
The streaming build system
Stacktrace.js
Framework-agnostic, micro-library for getting stack traces in all web browsers
Csscritic
A lightweight framework for regression testing of Cascading Style Sheets
Headstart
An automated front-end setup