Over two years ago, David Lee submitted a pull request which mapped the PATCH HTTP verb to update controller actions to follow proper REST semantics. This change is finally making its way into Rails as of version 4.0.

After maintaining the memcache-client gem for over two years, Mike Perham wrote Dalli. Dalli is a high performance drop-in replacement for memcache-client, and has been the client of choice for the last two years.

As of Rails 4, ActiveResource has been extracted to a gem named activeresource. Since the extraction, development for ActiveResource has been reinvigorated. A small team, lead by Jeremy Kemper, is now adding new features to ActiveResource.

We at Remarkable Labs really hope you've enjoyed the series, and to finish it off, I wanted to announce that we will be writing an ebook, titled "The Rails 4 Upgrading Guide".

MailCatcher is a ruby gem that runs a local SMTP server on your machine. Any email message sent to this SMTP server will be captured and not sent out. Also, all messages will be viewable in a web interface available at http://localhost:1080.