The datejs Javascript library ready to play with Rails

DependentFields makes it easy to hide or show dependent fields in forms based on select or checkbox values

Simple javascript timezone detection

Add UID support to Devise

Rails asset pipeline plugin and CSS mappings for the Entypo pictograms by Daniel Bruce http://www.entypo.com

Rails 3.2/4.x asset gem for EpicEditor

Asset gem for es5-shim

A polyfill for ES6-style Promises with integration for Rails.

Fomantic UI, converted to Sass and ready to drop into Rails, Compass, or Sprockets.

Programmatically generate assets for the Rails asset pipeline.

Instant concurrent indexes for Rails

Allows multiple environments in database.yml, and dynamically switching them.

Provides Holder.js to render image placeholders entirely on the client side

Plug-in that provides I18n Inflector module integration with Rails.

Optimize image assets using image_optim

jQuery Colorbox integration for Rails 3.1+ asset pipeline

The jQuery Query Builder Rule Evaluator and JavaScript library + Dependencies ready for the Rails Asset Pipeline.

A jQuery timepicker plugin inspired by Google Calendar

It achieves this by linting your code through a library called JSHint which catches most code smells, and ensures code consistency

This gem provides JSON Editor for your Rails 4+ application.