Wikimedia Foundation

We believe that knowledge should be free for every human being. We prioritize efforts that empower disadvantaged and underrepresented communities, and that help overcome barriers to participation. We believe in mass collaboration, diversity and consensus building to achieve our goals.

We have other content projects including Wikimedia Commons, Wikidata and the most recent one, Wikivoyage. We also maintain the MediaWiki engine and a wide collection of open source software projects around it.

But there is much more we can do: stabilize infrastructure, increase participation, improve quality, increase reach, encourage innovation, and you can help us reach these goals in many ways!



Under the “MediaWiki” umbrella there are actually hundreds of projects that sysadmins may select and combine according to their needs. The basic architecture is: 1. MediaWiki core is the wiki engine, mostly written in PHP; 2. Extensions to provide additional features. Chances are that you will start fixing a bug in an extension. Most are written in PHP, but depending on the extension you may find plenty of Javascript, plus other languages for niche cases. Javascript based, they offer customizations to the user experience. Some are provided server side, and they can also be run client side by the users; 3. Templates are functionality inserted in the content of the articles to provide text values, tables and other content related features. They are as editable as text, traditionally written in Wikitext but now moving to Lua; 4. Skins, which control the look & feel. Written in PHP; and Mobile apps, with native development focused in Android and iOS and we help contributors covering other platforms.

More Information
Code Repository
Issue Tracker
Main Languages, Frameworks, Environments
Mainly Javascript; PHP; Lua - see above for more detail


We have a wide and very diverse community! It is also somewhat chaotic, based on organic growth, decentralized efforts...just like Wikipedia itself. The bad news is that it is easy to get confused or even lost at first. The good news is that no matter who you are and what you are looking for, if you love Wikipedia there is probably a corner with people and projects fitting your interests.

The Wikimedia Foundation oversees the development and maintenance of the software projects and technical infrastructure behind Wikipedia and sister projects. Counting all the language variants they are more than 860 wikis! If you fix a bug, most probably you will be improving each of them. Check the Wikimedia Engineering pages to learn more about this team of about 70 members, half of it based in the San Francisco headquarters and the rest working remotely from all continents (except Africa - working on it).

How to contribute gives a good overview of the different areas in which our technical community is organized.

MediaWiki is also used by thousands of 3rd party organizations, and is the place where all developers converge.


Any potential contributor new to our community is encouraged to follow the Landing instructions. Use your user page to introduce yourself and point to the projects you are involved.

To set up your MediaWiki developer environment, we recommend you start installing a local instance using mediawiki-vagrant. You can also have a fresh MediaWiki to test on a remote server. Just get developer access and request your own instance at Wikitech.

Our Developer Hub provides important information for contributors, especially the API and the tutorial How to become a MediaWiki hacker. Instructions for working in our GitHub code repo are at Gerrit; and instructions for our issue tracker are at Bugzilla.

If you are working on a specific bug, use the related bug report to ask questions and report updates. For quick & casual support you can try at #mediawikiconnect IRC channel, a good place to find people with answers or at least good pointers.

Subscribe to wikitech-announce to receive announcements of new activities for tech contributors. Check out also our social media handlers. If you feel like learning more about the MediaWiki community and being part of it then go ahead and introduce yourself at the wikitech-l mailing list.