Haml-rails provides Haml generators for Rails 3. It also enables Haml as the templating engine for you, so you don't have to screw around in your own application.rb when your Gemfile already clearly indicated what templating engine you have installed. Hurrah.

A wysiwyg text editor for Bootstrap

Integration between Ember CLI and Rails

Easy upload management for ActiveRecord

A plugin for versioning Rails based RESTful APIs.

The library allows you to easily build datagrid aka data tables with sortable columns and filters

Deface is a library that allows you to customize ERB, Haml and Slim views in a Rails application without editing the underlying view.

The minitest-spec-rails gem makes it easy to use the \ Minitest::Spec DSL within your existing Rails test suite.

Deliver assets for Rails.

jQuery File Upload by Sebastian Tschan integrated for Rails 3.1+ Asset Pipeline

A thin wrapper to use Rails Migrations in non Rails projects

Swagger UI as Rails Engine for grape-swagger gem.

A native development UI for ViewComponent

A Rails engine for queuing and managing maintenance tasks

A thin wrapper to use Rails Migrations in non Rails projects

Adds methods to ActiveRecord::Migration to create and manage database functions and triggers in Rails

Konacha is a Rails engine that allows you to test your JavaScript with the mocha test framework and chai assertion library. It is similar to Jasmine and Evergreen, but does not attempt to be framework agnostic. By sticking with Rails, Konacha can take full advantage of features such as the asset pipeline and engines.

Speeds up the Rails 3 asset pipeline by only recompiling changed assets

Chosen is a javascript library of select box enhancer for jQuery and Protoype. This gem integrates Chosen with Rails asset pipeline for easy of use.

Protect attributes from mass assignment