Ruby on Rails, often called Rails, is an open source web application framework written in Ruby. Created by David Heinemeier Hansson and released in 2004, it popularized the idea of building web applications quickly by following sensible conventions.
What it is
Rails is a server side framework built on the model view controller pattern. Its guiding principles are convention over configuration, which means defaults are chosen so that developers write less setup code, and don’t repeat yourself, which means each piece of knowledge should live in one place. It uses the active record pattern to connect program objects to database tables. It is released under the MIT license.
History
Hansson extracted Rails from his work on the Basecamp project management tool at 37signals and released it as open source in July 2004. Version 1.0 arrived in December 2005, and in 2005 he received an award as hacker of the year from O’Reilly for the work. Rails 3.0, in August 2010, merged in the Merb framework. Later major versions include 4.0 in June 2013, 5.0 in June 2016, 6.0 in August 2019, 7.0 in December 2021, 8.0 in November 2024 and 8.1 in October 2025.
Who uses it
Well known sites built with Rails include Airbnb, GitHub, Shopify, Twitch, Crunchbase and Dribbble. Its emphasis on getting a working product running quickly made it a favorite of early stage startups and solo builders.
Why it matters to founders
Rails shaped a generation of web startups and still appeals to small teams that value productivity over novelty. Many ideas it popularized, from database migrations to generators, spread to other frameworks.
Related entries
See David Heinemeier Hansson, Basecamp, Shopify and Vibe coding.
Ruby on Rails is part of Tools and stack.
Sources
Wikipedia entries for Ruby on Rails and David Heinemeier Hansson. Reviewed October 2026.
