As I promised at RailsConf, we’re finally good to go on the Rails 3.1: Release Candidate. This is a fantastically exciting release. We have three new star features and an even greater number of just awesome improvements. First the stars:

The Asset Pipeline

The star feature of 3.1 is the asset pipeline powered by Sprockets 2.0. It makes CSS and JavaScript first-class code citizens and enables proper organization, including use in plugins and engines. See my RailsConf keynote for a full tour. This comes with SCSS as the default for stylesheets and CoffeeScript as the default for JavaScript. Much documentation is on the way for this.

HTTP Streaming

This lets the browser download your stylesheet and javascripts while the server is still generating the response. The result is noticeable faster pages. It’s opt-in and does require support from the web server as well, but the popular combo of nginx and unicorn is ready to take advantage of it. There’s a great Railscast on HTTP streaming and the API documentation is strong too.

jQuery is now the default

We’ve made jQuery the default JavaScript framework that ships with Rails, but it’s silly easy to switch back to Prototype if you fancy. It’s all bundled up in the jquery-rails and prototype-rails gems. Just depend on the one you’d like in the Gemfile and it’ll Just Work.

Other good stuff:

You can also check out the an even longer changelog and get a video overview from Railscast.

If you’re starting a new application, it’s strongly recommended that you do so using Ruby 1.9.2. Rails will continue to support 1.8.x until Rails 4.0, but it’s considered the legacy option. Ruby 1.9.x is where the action is. Get on board and enjoy the massive speed boost.