The report covering Wikimedia engineering activities in April 2014 is now available.

Wiki version: https://www.mediawiki.org/wiki/Wikimedia_engineering_report/2014/April
Blog version: https://blog.wikimedia.org/2014/05/14/engineering-report-april-2014/

We're also proposing a shorter, simpler and translatable version of this report that does not assume specialized technical knowledge: https://www.mediawiki.org/wiki/Wikimedia_engineering_report/2014/April/summary

Below is the HTML text of the report.

As always, feedback is appreciated on the usefulness of the report and its summary, and on how to improve them.


Major news in April include:

Note: We’re also providing a shorter, simpler and translatable version of this report that does not assume specialized technical knowledge.

Engineering metrics in April:



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Technical Operations

Datacenter RFP

The Wikimedia Foundation has chosen a winning RFP bid, a contract has been executed and implementation is underway. A public announcement is being prepared in the upcoming week.

Wikimedia Labs

Labs metrics in April:

  • Number of projects: 153
  • Number of instances: 345
  • Amount of RAM in use (in MBs): 1,454,592
  • Amount of allocated storage (in GBs): 16,515
  • Number of virtual CPUs in use: 716
  • Number of users: 3,064
The migration of Labs and Tool Labs to the Ashburn data center is complete, and most of the hardware in Tampa has been shut down and packed up for shipping to the new (to be announced) data center.
Post-migration, many projects which had public IPs are now relying on the internal Labs web proxy instead. That has caused a few unexpected bugs in project web access, but provides several benefits including HTTPS access and increased user data privacy.

Tampa data center

During the last month, our data center footprint in Tampa has been reduced to just 6 racks, reduced from 24 total. A copy of all essential data remains present in the Tampa facility until we’ve finished setting up the relevant services in our upcoming new data center.

Features Engineering

Editor retention: Editing tools


In April, the VisualEditor team worked to improve the stability of the editor, adding some new features and improving usability so that users can create and edit pages more swiftly and intuitively with VisualEditor than before. Template editing was over-hauled to make adding parameters less busy, showing only a few parameters at first rather than all possible ones, which can number in the dozens or more, especially in the case of some often-used templates like those for citations or infoboxes. Setting the size of images was tweaked to give a more natural set of controls based on feedback from users. The page settings dialog had a number of minor tweaks, leading to the set of options that can be modified inside VisualEditor being completed. VisualEditor’s edit tab is now more consistent with the rest of the MediaWiki interface in a number of noticeable if minor ways, such as on pages to do with the Education Program, on file pages which are hosted on Commons rather than on the local wiki, or on very narrow screens. User testing was carried out on the forthcoming citation dialog and some final simplifications were made, such as adding suggested as well as required parameters, ahead of its pending introduction. Finally, a careful audit of all Wikimedia wikis led to fixing broken local community-written code, to ensure that VisualEditor runs on all of them. The deployed version of the code was updated four times in the regular release cycle (1.23-wmf211.23-wmf221.24-wmf1 and 1.24-wmf2).


In April, the Parsoid team continued to fix bugs and tweak code. Two areas in particular received a lot of attention: template encapsulation and link handling. We ironed out a whole bunch of edge case handling in template encapsulation code and its interaction with fostered content from tables (caused by misnested tags in tables). We also fixed many unhandled scenarios and edge cases parsing and serializing links. In addition to bug fixes, we also improved the performance of the parsing pipeline; some pages like Barack Obama should now parse 30% faster than before. We continued migrating our debugging and tracing code to use our new logger. April also saw additional progress providing support for visual editing of transclusion parameters; this should land on master soon.

Core Features


This month, the Flow team focused on back-end changes to improve moderation and history viewing, as well as implementing new front-end JavaScript templating to make Flow more responsive and easier to add new features onto. On the user-facing features side, we released the ability to close and summarize topics. This will allow users to manage active discussions and end ones that have come to a resolution. Flow is now the default discussion experience for many Beta Features discussions on mediawiki.org, and the team is accepting requests to enable Flow on more pages on that wiki for the purpose of testing complex multi-user discussion interactions.



In April, Growth switched gears to focus on a new experimental area: anonymous editor acquisition. The team prepared its first two experimental interface changes, aimed at asking anonymous editors to register accounts(expected to be launched in early May). The team also will be conducting basic research into the role anonymous editors play in Wikipedia − more at Research:Anonymous phenomena and Research:Anonymous editor acquisition.


Wikipedia Education Program

This month we deployed several bug fixes, including disabling the malfunctioning and little-used student profilesfeature and setting a sensible default end date for new courses. Thanks to volunteer Tony Thomas, the extension-related preferences were moved into the Appearance tab of Preferences. Progress toward several other improvements was made in April: Sage Ross began implementing an API to generate lists of enrolled student editors from one or more courses, and the Facebook Open Academy students continued their work on new notification features, and also embarked on need-finding research for an improved course activity feed.


Wikimedia Apps

The Mobile App team continued moving toward the first market release of the rebooted Wikipedia App for Android and iOS. The team focused on bug fixes, editing refinements, and UX polish. Several issues related to keyboard, navigation bar, edit summary, and abuse filter were fixed. The app now uses the newly created Wikifont which reduced the size of the app and the number of graphical assets. Articles should now look even closer to their mobile web counterparts. Product management switched from Kenan Wang to Maryana Pinchuk due to Kenan’s departure, and the team welcomed Dmitry Brant as an Android software developer.

Mobile web projects

This month, the mobile web team released history and contributions pages, as well as an updated watchlist view, for all users. We also promoted two new features geared toward “humanizing” Wikipedia for readers and new editors: a prominent “last modified” banner that indicates when articles haven’t been edited in a while and may need some attention, and a user profile feature to provide a mobile-friendly snapshot of users’ contributions and activity. For tablets, we updated typography and layout and worked on adding the ability to add and modify links via VisualEditor in beta, in preparation for redirecting tablets to the mobile site later this quarter.

Wikipedia Zero

Presentation slides from the monthly metrics meeting

During the last month, the team continued setup tasks on the Partners portal, JSON configuration store, and graceful image quality reduction. The team also updated Android and iOS Wikipedia app reboot visual flourishes for Wikipedia Zero, analyzed anomalous access patterns and proxy-oriented configuration and tech documentation to close gaps, and created bugfixes for unnecessary charge warnings in the “Read in another language” language picker plus direct upload.wikimedia.org image hyperlinks on File: pages. The team also removed some legacy ETL code from the ZeroRatedMobileAccess extension.

Yuri did outreach abroad and continued analytics work on SMS/USSD pilot data. The team also generated two custom pageview analyses for an operator to distinguish traffic by high level device access characteristics as part of ongoing discussions. The team also explored legacy Android Wikipedia app trends.

Additionally, the team cut Android Wikipedia app alpha builds, worked on User-Agent string and URL format updates for the forthcoming iOS Wikipedia app to ensure pageview logging, and performed app code review.

Discussion with the community on MCC-MNC logging to address mobile IP drift was conducted, and it appears it is okay to proceed; the team will reduce the date granularity of log lines to the day (e.g., YYYYMMDD) with a patch to MediaWiki core, though.

Routine pre- and post-launch configuration changes were made to support operator zero-rating, and in-depth technical assistance was provided to operators and the partner management team to help add zero-rating and address anomalies.

The team emailed further about full-text search in reboots of Wikipedia apps, and may resume investigation of it later.

The team also examined requirements for portal and general partners engineering human resources.

Wikipedia Zero (partnerships)

IPKO in Kosovo launched Wikipedia Zero, bringing us to a total of 28 partners in 26 countries. We delivered 68 million free page views in April. Adele Vrana visited South Africa to meet with MTN (current Wikipedia Zero partner), prospective partners, members of Wikimedia South Africa (WMZA) and the Singenjongo High School. This trip was part of a broader strategy to promote Wikipedia in our partners’ corporate social responsibility (CSR) and education initiatives, increasing awareness and impact locally. We are identifying new collaboration opportunities with MTN and local organizations, including the Wikimedia chapter in South Africa and other mission-aligned nonprofits. Additionally, we will continue to support the local initiative created by Sinenjongo High School teachers and students. 

Language Engineering

Language tools

The team prepared the migration of the translation memory infrastructure from Solr to ElasticSearch.


The jquery.webfonts library was adapted for the Typography refresh. An input method for the Batak script was added to jquery.ime, and bugs were fixed in the InScript input method for Hindi, Odia and Gujarati.

Language Engineering Communications and Outreach

The team prepared targeted mini-surveys for readers of Wikipedia in poorly-supported languages, and heldIRC office hours.

Content translation

ContentTranslation was the team’s main effort this month. Source text segmentation was further improved and stabilized. Other developed features include:

  • A beta feature that shows a red interlanguage link when the article is not translated to the user’s language;
  • Basic handling of templates and images;
  • Basic publishing of the translation as a formatted article;
  • Testing infrastructure for the server.

Platform Engineering

MediaWiki Core


Work on the Zend plugin compatibility layer is feature complete, and now the team is working on proper packaging of HHVM, and is working toward making HHVM the default PHP implementation on the Beta cluster.

Release & QA

Presentation slides of the Release engineering and QA quarterly review. See also the agenda and minutes.

The tool that deploys code in production (“scap”) is now used to deploy/update code on the Beta cluster, removing another difference between the Beta cluster and production along with providing us an environment to safely test changes to our deployment system(s). We converted more scap code to python (scap-rebuild-cdbs and mw-update-l10n), and moved a ton of Jenkins jobs from the Cloudbees Jenkins to our self-hosted instance; we’re on target to end the use of Cloudbees’ Jenkins in the next two weeks. We also made significant progress on the two open positions (Release Engineer and QA Automation).


Auth systems

We did initial work on Authn/z requirements for RFC architecture, and an initial review of Requests for comment/AuthStack. We also investigated the use of MediaWiki’s OAuth for Phabricator, and worked on a proof of concept.

Wikimania Scholarships app

Several small bug fixes and feature requests were worked on by volunteers applying for GSoC projects. No operational issues were reported.

Deployment tooling

We started investigating changes that may be needed to support the use of HHVM in production.

Security auditing and response

We helped with the operational response to the Heartbleed vulnerability. Significant work was done on identifying and testing static analysis tools to integrate into the release workflow. We finished reviewing varnishkafka for Analytics, and Compact Personal Bar for UX. MediaWiki releases 1.21.9 and 1.22.6 fixed one security issue.

Quality assurance

Quality Assurance

This month saw the QA team working closely with the MobileFrontend team to extend and refactor their test suite. We also made great progress in running many of the browser test suites on headless Firefox instances in builds controlled by WMF Jenkins. Work on the WMF Jenkins browser test builds will continue in order to take advantage of the power and flexibility we have there.

Browser testing

The QA team released a number of new browser test features, including the ability to create test data in the target wiki at runtime. This feature was immediately put into use by the MobileFrontend team in their browser test suite. Acomplete list of shared features available to any browser tests in any extension repository is available.



In April, the multimedia team released Media Viewer v0.2 on 14 pilot sites, in preparation for a wider deploymentnext month: overall response has been favorable so far, and a growing majority of survey respondents are finding this new multimedia browser useful. Gilles Dubuc, Mark Holmquist, Gergő Tisza and Aaron Arcos developed final features for this release, as described on this release’s wall, based on designs by Pau Giner. We also developed a set of metrics dashboards to track global activity, image load and network performance, as well as local metrics dashboards for selected sites: first results show a decline in image load time, and suggest that Media Viewer loadsfaster than file description pages. We invite you to test the latest version of Media Viewer (see these testing tips) and share your feedback.

Fabrice Florin led product planning and management, hosting a planning meeting for our next development cycle (leading to a wall of tasks): for the next six weeks, we plan to divide our time between Media Viewer (e.g. serious bugs, basic zoom feature), Technical Debt (e.g. image scalers) and Upload Wizard. Keegan Peterzell and Fabrice announced the gradual release of Media Viewer on dozens of wiki sites, starting new discussions in collaboration with our community partners, as well as launching surveys in multiple languages to get reader feedback about this tool. For more updates about our multimedia work, we invite you to join the multimedia mailing list.

Engineering Community Team

Bug management

Daniel Zahn and Andre Klapper upgraded Wikimedia Bugzilla to the latest version 4.4.4. Valhallasw replaced the brittle wikibugs IRC notification bot by pywikibugs (announcement). A bugday took place updating about 50 MediaWiki General/Unknown tickets. Bugzilla’s “Tools” product was renamed to “Utilities” to decrease confusion with tools on Tool Labs. Numerous old forgotten “Backport_WMF?” flags on bug reports, older PATCH_TO_REVIEW tickets with all patches merged, and a lot of older WikiEditor tickets were cleaned up. In general, work mostly concentrated on handling the Phabricator RfC.

Project management tools review

On April 14, the Request for comment was finalized and a related FAQ published. The RfC was announced on thewikitech-lmediawiki-l and teampractices mailing lists, asking everybody for feedback on the RfC itself, discussion on its talk page, actively trying out proposed “Phabricator” in a testing instance, and creating tickets in the test instance under the “Wikimedia Phabricator” project for functionality that is missing.

Mentorship programs

Sixteen Google Summer of Code students and seven FOSS Outreach Program for Women interns will be busy in the next months working on Wikimedia projects. We got 23 participants in total, two more than a year ago, even if our quality criteria have been more strict this time.

Technical communications

In addition to ongoing communications support for the engineering staff, Guillaume Paumier organized and archived many team documentation pages of the Engineering Community Team, like planning pages, reports and meeting notes. He also set up subscription templates on mediawiki.org and the English Wikipedia that display the latest version of the technical newsletter for users who prefer not to get it delivered on their talk page.

Volunteer coordination and outreach

We restarted the Wikimedia Tech Talks with a light process for scheduling events, and we help organizing A preliminary look at Parsoid internals and Unit testing for MediaWiki projects. The Wikimedia Hackathon in Zürich is ready to roll on May 9−11, and we co-hosted and info session with Wikimedia Switzerland, the main organizers of the event.

Architecture and Requests for comment process

We held several Request for Comment review meetings in IRC:

Also, we worked on improving security, architecture, and performance guidelines for developers. We aim to have MediaWiki performance guidelines ready to approve at the Zürich hackathon in mid-May.



New features have been deployed on Wikimetrics: Scheduled Reports & Public Reports.


Data from text Varnishes is now being consumed through varnishkafka -> kafka -> camus into hdfs. Kafka now processes Bits, Images and Text data.


The Kiwix project is funded and executed by Wikimedia CH.

We have finally released a first experimental ZIM file of TED talks. We have packed in a unique 7GB library the 250 talks about business. This includes not only the videos, but also short speaker bios and thousands of subtitles in more than 50 languages. We will fix soon the last critical issues and release other TED ZIM files with talks about entertainment, science, etc.
We have also migrated our download server to a better one. Besides providing a better storage system and more bandwidth, it has 9TB of disk space. This was a mandatory step in our ZIM generation industrializing process and therefore necessary to allow us to generate more ZIM files more often.
We are also working with an e-reader manufacturer to have Kiwix installed and available on its devices so that theMALeBOOKS project (eBooks for Mali) can ship e-readers with not only thousands of free eBooks, but also the complete Wikipedia and Wikisource in French.


Presentation slides on Wikidata from the monthly metrics and activities meeting

The Wikidata project is funded and executed by Wikimedia Deutschland.

The Wikidata team got simple query functionality ready for a first demo at the WMF Metrics and Activities Meeting. The entity suggester a team of students is working on also got finishing touches and should be ready for release soon. Once it is live, it will suggest missing information on an item so it is easier to see what should be added. We also welcomed 2 interns as part of the Outreach Program for Women to help with documentation, social media outreach and mobile app concepts. Wikiquote now manages its language links via Wikidata. Additionally it is now possible to automatically add links to other sister projects in the sidebar of an article using Wikidata. A Wikidata Toolkit was released, as well as a library that lets you use Wikidata’s labels for translation anywhere on the web.


The engineering management team continues to update the Deployments page weekly, providing up-to-date information on the upcoming deployments to Wikimedia sites, as well as the annual goals, listing ongoing and future Wikimedia engineering efforts.

This article was written collaboratively by Wikimedia engineers and managers. See revision history and associated status pages. A wiki version is also available.

Guillaume Paumier
Technical Communications Manager — Wikimedia Foundation