biilly's doodle.js at master - GitHub

Johnson wraps JavaScript in a loving Ruby embrace. It embeds the Mozilla SpiderMonkey JavaScript runtime as a C extension.

The Holy Grail of testing for front-end development; execute browser-less, console-based, javascript + DOM code right from within your Rails test suite.

Run your Jasmine specs without a browser

Helium accepts a list of URLs for different sections of a site then loads and parses each page to build up a list of all

PaintbrushJS is a lightweight, browser-based image processing library that can apply various visual filters to images within a web page.

Capybara sets up some tags for you to use in Cucumber. Often you’ll want to run only some scenarios with a driver that supports JavaScript, Capybara makes this easy: simply tag the scenario (or feature) with @javascript:

Reads Active Record's validations and makes them available to live client side javascript

A Rails plugin that delivers a special message to DiggBar users, or runs frame-killer javascript.

Hanna is an RDoc template that scales. It's implemented in Haml, making the sources clean and readable. It's built with simplicity, beauty and ease of browsing in mind.