More at rubyonrails.org: More Ruby on Rails

Ruby on Rails Guides (4a86464)

These are Edge Guides, based on master@4a86464.

If you are looking for the ones for the stable version, please check https://guides.rubyonrails.org instead.

The guides for earlier releases: Rails 5.2, Rails 5.1, Rails 5.0, Rails 4.2, Rails 4.1, Rails 4.0, Rails 3.2, Rails 3.1, Rails 3.0, and Rails 2.3.

Guides marked with this icon are currently being worked on and will not be available in the Guides Index menu. While still useful, they may contain incomplete information and even errors. You can help by reviewing them and posting your comments and corrections.

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Getting Started with Rails

Everything you need to know to install Rails and create your first application.


Active Record Basics

This guide will get you started with models, persistence to database, and the Active Record pattern and library.

Active Record Migrations

This guide covers how you can use Active Record migrations to alter your database in a structured and organized manner.

Active Record Validations

This guide covers how you can use Active Record validations.

Active Record Callbacks

This guide covers how you can use Active Record callbacks.

Active Record Associations

This guide covers all the associations provided by Active Record.

Active Record Query Interface

This guide covers the database query interface provided by Active Record.

Active Model Basics
Work in progress

This guide covers the use of model classes without Active Record.


Action View Overview
Work in progress

This guide provides an introduction to Action View and introduces a few of the more common view helpers.

Layouts and Rendering in Rails

This guide covers the basic layout features of Action Controller and Action View, including rendering and redirecting, using content_for blocks, and working with partials.

Action View Form Helpers

Guide to using built-in Form helpers.


Action Controller Overview

This guide covers how controllers work and how they fit into the request cycle in your application. It includes sessions, filters, and cookies, data streaming, and dealing with exceptions raised by a request, among other topics.

Rails Routing from the Outside In

This guide covers the user-facing features of Rails routing. If you want to understand how to use routing in your own Rails applications, start here.

Other Components

Active Support Core Extensions

This guide documents the Ruby core extensions defined in Active Support.

Action Mailer Basics

This guide describes how to use Action Mailer to send emails.

Action Mailbox Basics
Work in progress

This guide describes how to use Action Mailbox to receive emails.

Action Text Overview
Work in progress

This guide describes how to use Action Text to handle rich text content.

Active Job Basics

This guide provides you with all you need to get started creating, enqueuing, and executing background jobs.

Active Storage Overview

This guide covers how to attach files to your Active Record models.

Action Cable Overview

This guide explains how Action Cable works, and how to use WebSockets to create real-time features.

Digging Deeper

Rails Internationalization (I18n) API

This guide covers how to add internationalization to your applications. Your application will be able to translate content to different languages, change pluralization rules, use correct date formats for each country, and so on.

Testing Rails Applications

This is a rather comprehensive guide to the various testing facilities in Rails. It covers everything from 'What is a test?' to Integration Testing. Enjoy.

Securing Rails Applications

This guide describes common security problems in web applications and how to avoid them with Rails.

Debugging Rails Applications

This guide describes how to debug Rails applications. It covers the different ways of achieving this and how to understand what is happening "behind the scenes" of your code.

Configuring Rails Applications

This guide covers the basic configuration settings for a Rails application.

The Rails Command Line

This guide covers the command line tools provided by Rails.

The Asset Pipeline

This guide documents the asset pipeline.

Working with JavaScript in Rails

This guide covers the built-in Ajax/JavaScript functionality of Rails.

The Rails Initialization Process
Work in progress

This guide explains the internals of the Rails initialization process.

Autoloading and Reloading Constants

This guide documents how autoloading and reloading constants work.

Caching with Rails: An Overview

This guide is an introduction to speeding up your Rails application with caching.

Active Support Instrumentation
Work in progress

This guide explains how to use the instrumentation API inside of Active Support to measure events inside of Rails and other Ruby code.

Using Rails for API-only Applications

This guide explains how to effectively use Rails to develop a JSON API application.

Active Record and PostgreSQL
Work in progress

This guide covers PostgreSQL specific usage of Active Record.

Extending Rails

The Basics of Creating Rails Plugins
Work in progress

This guide covers how to build a plugin to extend the functionality of Rails.

Rails on Rack

This guide covers Rails integration with Rack and interfacing with other Rack components.

Creating and Customizing Rails Generators & Templates

This guide covers the process of adding a brand new generator to your extension or providing an alternative to an element of a built-in Rails generator (such as providing alternative test stubs for the scaffold generator).

Getting Started with Engines
Work in progress

This guide explains how to write a mountable engine.

Threading and Code Execution in Rails
Work in progress

This guide describes the considerations needed and tools available when working directly with concurrency in a Rails application.


Contributing to Ruby on Rails

Rails is not 'somebody else's framework.' This guide covers a variety of ways that you can get involved in the ongoing development of Rails.

API Documentation Guidelines

This guide documents the Ruby on Rails API documentation guidelines.

Guides Guidelines

This guide documents the Ruby on Rails guides guidelines.


Maintenance Policy

What versions of Ruby on Rails are currently supported, and when to expect new versions.

Release Notes

Upgrading Ruby on Rails

This guide helps in upgrading applications to latest Ruby on Rails versions.

6.0 Release Notes
Work in progress

Release notes for Rails 6.0.

Version 5.2 - April 2018

Release notes for Rails 5.2.

Version 5.1 - April 2017

Release notes for Rails 5.1.

Version 5.0 - June 2016

Release notes for Rails 5.0.

Version 4.2 - December 2014

Release notes for Rails 4.2.

Version 4.1 - April 2014

Release notes for Rails 4.1.

Version 4.0 - June 2013

Release notes for Rails 4.0.

Version 3.2 - January 2012

Release notes for Rails 3.2.

Version 3.1 - August 2011

Release notes for Rails 3.1.

Version 3.0 - August 2010

Release notes for Rails 3.0.

Version 2.3 - March 2009

Release notes for Rails 2.3.

Version 2.2 - November 2008

Release notes for Rails 2.2.


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Please contribute if you see any typos or factual errors. To get started, you can read our documentation contributions section.

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