What are all those gems that are installed/used by Rails

Wonder what all those gems are that you find being installed/used when you do:

rails new app

Here’s a breakdown (all gems can be found doing a search on http://rubygems.org/)

Using rake (10.0.4)

Ruby Make


Using i18n (0.6.4)

Internationalization for Ruby


Installing minitest (4.7.4) 

minitest is a complete suite of testing facilities supporting TDD, BDD, mocking and benchmarking


Using multi_json (1.7.3) 

A gem to provide easy switching between different JSON backends, including Oj, Yajl, the JSON gem (with C-extensions), the pure-Ruby JSON gem, and OkJson.


Using atomic (1.1.9) 

an Atomic class that guarantees atomic updates to its contained value


Using thread_safe (0.1.0) 

A collection of thread-safe versions of common core Ruby classes


Using tzinfo (0.3.37)

TZInfo is a Ruby library that uses the standard tz (Olson) database to provide daylight savings aware transformations between times in different time zones.


Using activesupport (4.0.0.rc1)

A toolkit of support libraries and Ruby core extensions extracted from the Rails framework. Rich support for multibyte strings, internationalization, time zones, and testing.


Using builder (3.1.4) 

Builder provides a number of builder objects that make creating structured data simple to do. Currently the following builder objects are supported: * XML Markup * XML Events


Using erubis (2.7.0) 

Erubis is an implementation of eRuby (Embedded Ruby), a templating system that embeds Ruby in a text document.


Using rack (1.5.2) 

Rack provides an interface for developing web applications.




Using rack-test (0.6.2) 


Using actionpack (4.0.0.rc1) 

Web apps on Rails


Using mime-types (1.23) 


Using polyglot (0.3.3) 

Polyglot provides a registry of file types that can be loaded by calling its improved version of ‘require’. It also allows a Ruby module to register a loader for the file type associated with a filename extension. 


Using treetop (1.4.12) 

A Ruby-based text parsing and interpretation DSL

Using mail (2.5.4) 

Ruby mail handler

Using actionmailer (4.0.0.rc1) 

Email on Rails

Using activemodel (4.0.0.rc1) 

Toolkit for building modelling frameworks like Active Record and Active Resource.

Using activerecord-deprecated_finders (1.0.2) 

Using arel (4.0.0) 

SQL AST (abstract syntax tree) manager for Ruby. It simplifies the generation of complex SQL queries.

Using activerecord (4.0.0.rc1) 

Databases on Rails. Build a persistent domain model by mapping database tables to Ruby classes.

Using bundler (1.3.5) 

Manage gems.

Installing coffee-script-source (1.6.2) 

Installing execjs (1.4.0) 

Installing coffee-script (2.2.0) 

Language that compiles into JavaScript.


Using thor (0.18.1) 

A scripting framework that replaces rake, sake, rubigen.

Using railties (4.0.0.rc1) 

see earlier post

Installing coffee-rails (4.0.0) 

CoffeeScript adapter.

Using hike (1.2.2) 

Finding files in a set of paths.

Installing jbuilder (1.0.2) 

Create JSON structures via a Builder-style DSL.

Installing jquery-rails (2.2.1) 

jQuery for Rails.

Installing json (1.8.0) 


Using tilt (1.4.1) 

Generic interface to multiple Ruby template engines

Using sprockets (2.10.0) 

Using sprockets-rails (2.0.0.rc4) 

Rack-based asset packaging system that concatenates and serves JavaScript, CoffeeScript, etc.

Using rails (4.0.0.rc1) 

should be pretty straightforward…!

Installing rdoc (3.12.2) 


Installing sass (3.2.9) 

Installing sass-rails (4.0.0.rc1) 

Extension to CSS3

Installing sdoc (0.3.20) 

rdoc generator

Installing sqlite3 (1.3.7) 

SQLite interface

Installing turbolinks (1.1.1) 

Turbolinks makes following links in your web application faster (use with Rails Asset Pipeline). Similar to pjax (pjax = pushState + ajax). Does not require jQuery but works great with jQuery.

Installing uglifier (2.1.1) 

Ruby wrapper for UglifyJS JavaScript compressor

Your bundle is complete!

And so is this whirlwind tour!

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