Rails 2.2 is finally done after we cleared the last issues from the release candidate program. This release contains an long list of fixes, improvements, and additions that’ll make everything Rails smoother and better, but we also have a number of star player features to parade this time.

Internationalization by default
The most important is that Rails now includes a full-on internationalization framework and that it’s pre-wired from start. The work of the i18n group has been very impressive and it’s great to see that Rails finally ships with a solution in the box that’s both simple and extensible. Great job, guys!

Stronger etag and last-modified support
We’ve also added much better support for HTTP validators in the form of etag and last-modified. Making it so much easier to skip expensive procesesing if the client already has the latest stuff. This also makes it even easier to use Rails with gateway proxies.

Thread safety and a connection pool
Josh Peek has added thread safety to Rails and Nick Sieger from JRuby worked on getting Active Record a proper connection pool. So now all elements of Rails are thread safe, which is a big boon for the JRuby guys in particular. For C Ruby, we still need a bunch of dependent libraries to go non-blocking before it’ll make much of a difference, but work on that is forth coming.

Ruby 1.9 and JRuby compatibility
Jeremy Kemper has been rocking on both Ruby 1.9 and JRuby compatibility. Rails 2.2 is fully compatible with both, but again, there might be supporting libraries and gems that are not. Again, lots of work is going into making everything else fully compatible as well.

Better API docs, great guides
Finally, the last big push has been with the documentation of Rails. Pratik’s docrails project has made immense progress. Not only are the API docs much improved, but we also have a whole new guides section generated from documentation that now lives with the source. A true community project with lots of contributors. I’m sure both those new and old to Rails will greatly appreciate the strong focus on documentation.

To read about all these features and more in details, checkout the Rails 2.2 release notes — another one of those guides from the docrails project.

How to install
As always, you can install Rails 2.2 through RubyGems. We now require RubyGems 1.3.1, so be sure to update that first: gem update --system

Then you can install Rails: gem install rails

If you’re updating an existing application, you can run rake rails:update to get the latest JavaScript files and scripts.

From all of us to all of you, we hope you enjoy this release. It’s a true pleasure to see Rails make such big steps forward once again. Dig in, have fun, and we’ll be back with Rails 2.3 with even more before you know it.