[Update 2011-09-24: The initial test deployment and stage 1 have gone well, with only minor glitches that we’ve mostly cleaned up.  Stage 2 and 3 are currently on schedule.  We’ve decided to add incubator.wikimedia.org to the list of wikis we’ll be deploying to, which is reflected below.]

MediaWiki 1.18 will soon be deployed to all Wikimedia sites, including Wikipedia. As you may know, MediaWiki is the wiki software developed by the Wikimedia community, and 1.18 is the upcoming version of the software that has been in development since December.

Thanks to the completion of the heterogeneous deployment project, we are now able to run different versions of MediaWiki concurrently on Wikimedia sites. This means that we don’t have to upgrade all sites at the same time any more, which should limit the problems we encounter.

The deployment is scheduled to happen in several stages, starting next week:

Wikis in Stage 1 and 2 may experience more issues, so we plan to focus our attention to those wikis during these periods, and be particularly responsive. If you’d like to help make sure we catch problems before we roll out to your wiki, please help us test, by trying out the test wiki starting Tuesday, and report the issues you find.

To report issues in real time during the upgrade windows, IRC is the best venue; please join us in #wikimedia-tech on Freenode (web access).

To provide feedback at other times, you have several choices. We still are happy to help people who approach us in IRC when we’re around. For those of you that are comfortable with Bugzilla and other development tools, we would love your help with confirming issues and getting appropriate issues filed in our bug tracker. If you don’t feel comfortable using Bugzilla, you can leave a message on the talk page of our announcement on meta. Our developers can keep track of issues much better when you use Bugzilla, so filing it there makes it more likely your problem will be noticed and eventually addressed.

Major features of MediaWiki 1.18 include:

  • Support for gender-specific user pages: languages that have different words for User whether the user is male or female will be able to show the male or the female version, if the user has specified their gender in their preferences.
  • Better directionality support: MediaWiki 1.18 will make it easier for left-to-right and right-to-left text to coexist on the same page. (Languages this affects include Hebrew, Arabic, and Farsi.)
  • Protocol-relative URLs, which will allow a wiki to support HTTP and HTTPS while serving the same HTML for both, thus avoiding a split in the parser cache.

The draft release notes provide a more complete list of noteworthy changes in MediaWiki 1.18.

Wikimedia uses a “deploy, then release” process: Once the upgrade is completed on all Wikimedia sites, and all issues are fixed, we will officially release MediaWiki 1.18 for use by third parties. This ensures that we release software that is as bug-free as possible.

The previous upgrade of Wikimedia sites to MediaWiki 1.17 happened in February this year, and revealed a large number of issues, because of the amount of changes that were included in the new version.

Wikimedia engineers have been working together relentlessly over the past few weeks to ready MediaWiki 1.18 for deployment. They have finalized the review of the code, and fixed all the issues they can find.

Recent efforts in code review have kept the amount of yet unreviewed code changes to a manageable level, which should result in more frequent upgrades. More systematic automated testing will also help developers build confidence in their code, and speed up the process for future releases.

For those of you developers who contributed to 1.18, thanks for your contribution and your patience during this release cycle.  To everyone else, thanks in advance for your patience as we get this deployed!

Rob Lanphier
Director of Platform Engineering

(p.s. thanks Guillaume for writing large swaths of this posting)