This page lists developers who know the most about, and help maintain, core MediaWiki components, key extensions and skins, libraries and other Wikimedia technical infrastructure.

Developer rolesEdit

  • Maintainers have +2 access to the relevant Git repository and they regularly respond to bug reports and changeset review requests. Anyone with a developer account can submit a patch for review, but only maintainers can merge changes. Anyone may participate in Phabricator and in Gerrit Code Review if they're interested in helping out and gaining experience that way. If you're seeking to become an active maintainer, feel free to contact a maintainer and share this desire and ask if they're willing and able to mentor and involve you proactively for a certain period of time.
If you are a maintainer, please consider using/configuring Gerrit to email you for new patchsets in a repository. Alternatively you can add yourself to the Gerrit Reviewer Bot which will automatically add you as a review to each new patchset.
  • Code Stewards are ultimately responsible for the development policies, support, and overall health of the code in question. They commit to a base level of support such as bug fixes and code reviews. For more information regarding stewardship, see Development policy/Code Stewardship.

Code StewardsEdit

Code stewardship coverage
% Assigned Trend

MediaWiki coreEdit

See also: Gerrit's list of mediawiki group members (core developers with +2 on all mediawiki repositories).
Not all the areas below actually have their own Phabricator project, or have not had #tags set up for alternate names yet.
Component Description Steward Maintainers
API MediaWiki's web-based "action" API that lets people interact with MediaWiki programmatically.

  • This includes the following files/paths: includes/api/
Core Platform Team Legoktm
Authentication and Authorization Components related to user authentication and authorization, including login and signup (AuthManager), password hashing and storage, session handling (SessionManager), and group permissions.

  • This includes the following files/paths: includes/auth/, includes/session/, includes/password/
Core Platform Team Parent5446, Gergő Tisza, Taavi Väänänen
Blocks Classes and functions related to user blocking mostly around Special:Block and related functions. Separating this out from User Management to reflect reality.
Anti-Harassment Tools Team
Comment store Storing comments such as edit summaries, and log action reasons. Including access layers, value interfaces, and their database schema.

  • This includes the following files/paths: includes/CommentStore.php, includes/CommentStoreComment.php
Core Platform Team
Categories All issues relating to categories.

  • This includes the following files/paths: includes/Category.php, includes/collation/
Unassigned Bawolff
Change tagging The feature that allows putting tags on revisions, log entries etc. added from edit filters in Extensions (AbuseFilter, TorBlock, etc).

  • This includes the following files/paths: includes/changetags/
Unassigned This, that and the other
Configuration The Config and ExtensionRegistry components, for registering and loading site configuration and extensions.

  • This includes the following files/paths: includes/config, includes/registration/
Core Platform Team Legoktm
ContentHandler Representation of content values and their formatting. For the storing of content, see Revision-backend instead.

  • This includes the following files/paths: includes/content
Core Platform Team Daniel Kinzler
Core testing Configuration and base classes for checkers, unit testing, and integration testing (PHPUnit, QUnit, etc).
Unassigned Timo Tijhof, Antoine Musso
Debug Logger Debug logging functions, debug toolbar, and PSR-3/Monolog integration.
DjVu All issues related to DjVu

  • This includes the following files/paths: includes/media/DjVuImage.php, includes/media/DjVu.php
Structured Data team (details and SLA)
Documentation Meta issues about MediaWiki core documentation both Doxygen/JSDuck-generated and on

  • This includes the following files/paths: docs/
Unassigned APaskulin, Timo Tijhof
Email Issues relating to the email notification features and email address verification (Special:Confirmemail etc.)

  • This includes the following files/paths: includes/mail/
Unassigned 01tonythomas
File management Management of uploaded files (images, thumbnails, etc.)

  • This includes the following files/paths: includes/filebackend/, includes/filerepo/
Gallery Gallery of media files as created by wikitext <gallery> tag.
Hooks Hook system
Core Platform Team Tim Starling
HtmlFormatter A library for HTML parsing and manipulation
HTML Templating Template parser class and configuration and its exposure via ResourceLoader
HTTP Cache CDN purging and FileCache storage. Performance Team Aaron Schulz, Timo Tijhof
Installer Installation, setup, and upgrade procedure.

  • This includes the following files/paths: includes/installer/, mw-config/
Interface and skin rendering Issues relating to the user interface handling and skin system.

  • This includes the following files/paths: includes/skins/, resources/src/mediawiki.skinning, includes/resourceloader/ResourceLoaderSkinModule.php
Reading mediawiki‑skins group, Bartosz Dziewoński
Internationalization All issues relating to internationalization, localization, translation, and the MediaWiki namespace.

  • This includes the following files/paths: languages/
Language engineering Raimond Spekking, Federico Leva
Interwiki Interwiki database and cache
JobQueue Job queue

  • This includes the following files/paths: includes/jobqueue/
Core Platform Team Aaron Schulz
Language converter Script conversion for several languages, e.g. Chinese and Serbian. (Problem area -- not much developer capacity here.)

  • This includes the following files/paths: languages/LanguageConverter.php, languages/FakeConverter.php
Content Transform Team Liangent, Robin Pepermans,

Chiefwei (Chinese language)

Logging Special:Log, mw_logging table

  • This includes the following files/paths: includes/logging/
Unassigned Umherirrender
Maintenance system The Maintenance script system in MediaWiki core.

  • This includes the following files/paths: maintenance/
Unassigned Sam Reed
Merge history The MergeHistory logic and its API and Special page frontend.
Metrics Metrics service for Statsd/Prometheus.

  • This includes the following files/paths: libs/Metrics/
SRE/Observability, Performance Team Cole White, Timo Tijhof
ObjectCache The wikimedia/objectcache library (BagOStuff, WANObjectCache, Redis/Memcached clients) and their MediaWiki integration.

  • This includes the following files/paths: includes/objectcache/, includes/libs/objectcache/
Performance Team Aaron Schulz, Timo Tijhof
Page deletion Issues related to deleting and undeleting/restoring pages and revisions (via action=delete and Special:Undelete).
Unassigned Aaron Schulz
Page derived data Management of data derived from a page, including PageUpdater, LinksUpdate, RefreshLinks, and the database for storing this derived data (such as page_props, and link tables).
Core Platform Team Daniel Kinzler
Page-Diffs All issues relating to the page displaying differences between two revisions (diff=, oldid=, type=revision in the URL).

  • This includes the following files/paths: includes/diff/
Page editing All issues relating to the edit screen, edit conflicts, and saving edits.
Editing team
Page-History All issues relating to the page displaying the history of revisions via the action=history view or Special:History page..

  • This includes the following files/paths: includes/diff/
Page protection Protection and unprotection of pages, and issues with protected pages
Core Platform Team
Parser Issues relating to the process that converts wiki syntax into HTML.
Content Transform Team C. Scott Ananian
Patrolling New page patrolling, edit patrolling. "[mark as patrolled]". rc_patrolled etc.
Unassigned Marius Hoch
Profiler Issues relating to Profiler.
Performance Team Timo Tijhof
Recent changes Bug reports and feature requests related to the special page RecentChanges.
Growth team
Redirects All issues relating to redirects.
Unassigned Sam Reed
Revision backend Issues related to the backend classes around revisions, blobs, and slots. Including Multi-Content-Revisions (MCR).
Core Platform Team
ResourceLoader ResourceLoader delivery and management system for loading modules in MediaWiki.
Performance Team Timo Tijhof, Roan Kattouw
Revision deletion Hiding and unhiding of individual page revisions, log entries and usernames and revision suppression.
Unassigned Aaron Schulz
Rdbms The wikimedia/rdbms library for interacting with relational databases, and its MediaWiki integration.

  • This includes the following files/paths: includes/db/, includes/libs/rdbms/
Performance Team Aaron Schulz, Timo Tijhof
Search Issues relating to the search engine. Note that Wikimedia web sites do not use the default MediaWiki search engine; please file bugs against their Search under "CirrusSearch" instead!
Search Platform
ServiceContainer Issues relating to ServiceContainer, MediaWikiServices, and loading of service wiring.
Core Platform Team
Sites Information about other sites
Shell Shell framework for calling external binaries.
Snapshots Issues relating to XML snapshot generation and loading (maintenance scripts, API, interface at Special:Export/Special:Import)

  • This includes the following files/paths: includes/snapshots/, includes/export/, includes/import/
Core Platform Team Ariel Glenn, Hannah Okwelum This, that and the other
Special pages All implemented special pages and the framework for special pages in general. Note that many features implemented as Special pages have their own dedicated components for the feature in general (Export/Import, Logging, Page deletion, Page protection, Recent changes, Search, Uploading, User blocking, User login, User preferences, Watchlist, …).
Unassigned This, that and the other
Templates All issues relating to templates and template inclusion.
Unassigned Jackmcbarn
Uploading File upload interface at Special:Upload. (Issues with already uploaded files should be filed under "File management")
User login and signup Account creation, login, etc. Settings bugs in this component should be moved to the "User preferences" component.
Core Platform Team
User management Permissions and authorization
Unassigned Jack Phoenix
User preferences The preferences system (sometimes known as user options or user properties), including the PreferencesFactory and UserOptionsManager services, their interface (Special/API), and database table.
Watchlist Bug reports and feature requests related to the special page Watchlist.
Growth team Watchlist Expiry: Community Tech

MediaWiki extensions deployed at Wikimedia FoundationEdit

See also: Category:Extensions used on Wikimedia and phab:source/mediawiki-config/browse/master/wmf-config/extension-list
Not all the areas below actually have their own Phabricator project, or have not had #tags setup for alternate names yet.
Extension Description Steward Maintainers
3d Enables upload of three-dimensional model files, and supports thumbnailing and interactive viewing in Media Viewer.
Structured Data team (details and SLA)
AbuseFilter Allows privileged users to set specific controls on actions by users, such as edits, and create automated reactions for certain behaviors
Core Platform Team Marius Hoch, Daimona Eaytoy, se4598, Matěj Suchánek
ActiveAbstract Used as part of dumpBackup
Unassigned ArielGlenn, Hannah Okwelum
AdvancedSearch Enhances Special:Search by providing an advanced parameters form
WMDE Engineering (contact EMs)
AntiSpoof Prevents creation of confusable usernames
Anti-Harassment Tools Sam Reed
ApiFeatureUsage Access API feature usage log summaries
Core Platform Team
Community Tech
ArticlePlaceholder Provides a special page with Wikidata information about a certain topic, with invitation to create an article for the topic
WMDE Engineering (contact EMs)
Babel Adds a parser function to inform other users about language proficiency and categorize users of the same levels and languages
Language team
BetaFeatures Allows other extensions to register their beta features in the user preferences
BounceHandler Allow MediaWiki to handle bounce email efficiently with VERP headers
Unassigned 01tonythomas, Jgreen (wmf)
Calendar Creates a Calendar in pages
Campaigns Allows to track user account creations related to campaigns
Capiunto Provides basic Infobox functionality for Scribunto
Unassigned Marius Hoch
CategoryTree Provides a dynamic view of the wiki's category structure as a tree
CentralAuth Allows to merge accounts into global accounts
Unassigned Under review

task T252244

Taavi Väänänen, Zabe
CentralNotice Adds a central sitenotice
Fundraising tech
CharInsert Create JavaScript character insert boxes
Editing team
CheckUser Allows a user with permissions to check which IPs are used by a given username and which usernames are used by a given IP
Core Platform Team
CirrusSearch Implements searching for MediaWiki using Elasticsearch
Search Platform
Cite Allows footnotes for citing sources and helps for correctly citing content in offline media
Editing team Marius Hoch
CiteThisPage Adds a special page that provides different citation formats for a particular article
Unassigned Marius Hoch
Citoid Extension part of the Citoid service
Editing team
cldr Import localisation data from CLDR
Language team Language team
CodeEditor Provides a syntax-highlighting code editor for site & user JS, CSS and Lua pages, integrating with advanced edit toolbar
Editing team Derk-Jan Hartman
CodeMirror Provides syntax highlighting in MediaWiki's wikitext editor.
Community Tech Pavel Astakhov
Cognate Centralises Wiktionary links into Wikidata
WMDE Engineering (contact EMs)
Collection Allows organization of personal selections of pages in a collection that can be edited, persisted and optionally retrieved as PDF, ODF or DocBook (XML)
Unassigned Under review

task T224922

C. Scott Ananianoriginally: PediaPress
CommonsMetadata Extracts metadata from commons pages
Structured Data team (details and SLA)
ConfirmEdit Adds CAPTCHAs for page saves and other user actions. Only QuestyCaptcha is supported.
Editing team Emufarmers, Florianschmidtwelzow
CongressLookup Allows users to look up contact info for their representatives
ContactPage Provides a contact form for visitors
Product Infrastructure (SLA details)
ContentTranslation Allows editors to translate an article from one language to another with the help of machine translation and other aids.
Language team Language team
CreditsSource Display source work credits in the page footer
Dashiki Renders the JSON used to configure dashiki dashboards in a friendly HTML table
Data Engineering
Disambiguator Enables the designation of disambiguation pages with a magic word
DiscussionTools Tools to enhance discussion pages
Editing team
DismissableSiteNotice Allows users to close the sitenotice
DonationInterface Provides fundraising mechanisms for collecting payments
Fundraising tech
DoubleWiki Compare wikis in two separate languages side by side
Unassigned Thomas PT (Tpt)
DynamicPageList (Wikimedia)

(aka Intersection)

Outputs a bulleted list of most recent items residing in a category, or an intersection of several categories
Unassigned Brian Wolff
DynamicSidebar Shows a dynamic sidebar based on user configuration
Unassigned Derick Alangi
EasyTimeline Produces an embedded timeline image from special syntax inside ‎<timeline> tags.
Echo MediaWiki's notification subsystem
Growth team Alex Monk
Elastica Provides base elasticsearch functionality
Search Platform
ElectronPdfService Converts wiki pages to PDFs using Electron.
WMDE Engineering (contact EMs)
EntitySchema Stores Shape Expressions Schemas on wiki pages (for Wikidata).
WMDE Engineering (contact EMs)
EventBus Propagates change events to a RESTful service. Transports data between arbitrary applications, in the form of events that conform to versioned schemas.
Data Engineering
EventLogging Provides logging and validation of web analytics events
Data Engineering
EventStreamConfig Exposes event stream configs in an API endpoint. Can also be used to expose configs via ResourceLoader.
Data Engineering Andrew Otto
ExtensionDistributor Enables the distribution of extensions from
Unassigned Tim Starling
ExternalGuidance Indicates to users that the wiki page being viewed is served through an external service, and provides ways to contribute back to the original wiki.
Language team
FeaturedFeeds Adds syndication feeds of wiki's featured content
Product Infrastructure (SLA details)
FileExporter Provides a link to export local files to another wiki that has the FileImporter extension.
WMDE Engineering (contact EMs)
FileImporter Allows for the easy importing of a file from one wiki to another.
WMDE Engineering (contact EMs)
FlaggedRevs Allows for article content management by "editor" and "reviewer" classes
Unassigned Under Review

task T185664

Aaron Schulz
StructuredDiscussions (aka Flow) A modern discussion and collaboration system
Growth team
FundraiserLandingPage Enables template parameters to be passed as querystring elements
Fundraising tech
FundraisingTranslateWorkflow Locks down translation publishing rights on selected pages
Fundraising tech Elliott Eggleston
FundraisingEmailUnsubscribe Donor-facing fundraising email unsubscribe form (on
Fundraising tech
Gadgets Allows users to enable JS-based, user-provided gadgets from their preferences page
Unassigned Roan Kattouw
GeoCrumbs Adds a trail of bread crumbs to the page
GeoData Adds geographical coordinates storage and retrieval functionality
Search Platform Team
GlobalBlocking Allows IP addresses to be blocked on multiple wikis
Unassigned Taavi Väänänen
GlobalCssJs Allows global CSS and JS on a "central" wiki to be loaded for all wikis in the farm
GlobalPreferences Allows a user to decide which user preferences to set as global (wikifarm-wide) and which to keep local.
Community Tech
GlobalUsage Enables viewing of global image use in a wiki farm with shared image repository
Structured Data team (details and SLA)
GlobalUserPage Enables global (shared between wikis) user pages on a wiki farm
GlobalWatchlist Allows a user to view changes to watched pages on multiple sites at once
(Active volunteer) DannyS712
GoogleNewsSitemap Outputs a list of pages based on what categories they are in as an RSS feed or Google news sitemap
Unassigned Brian Wolff
Graph Data-driven graphs
Editing team Yurik
GrowthExperiments Contains experiments done by the Growth team
Growth team Stephane Bisson
GuidedTour Delivers guided tours
Growth team Matt Flaschen
GWToolset Mass upload of content based on provided metadata
Structured Data team (details and SLA)
ImageMap Allows clickable HTML image maps
Editing team
ImageSuggestions Image recommendation features for experienced users
Structured Data team (details and SLA)
InputBox Allows users to add predefined HTML forms to wiki pages
Unassigned Jackmcbarn
Insider Lists volunteer tour guides for travel destinations
Interwiki Adds a special page to view and manipulate the interwiki table
InterwikiSorting Allows sorting of interwiki links
WMDE Engineering (contact EMs)
IPInfo Displays IP information for anti-vandalism purposes
Anti-Harassment Tools Team
Josa Automates josa part of Korean postposition process
JsonConfig Provides a wiki-based JSON configuration system
Product Infrastructure (SLA details) Yurik
Kartographer Allows adding maps to pages
Content Transform Team Mateus Santos
LabeledSectionTransclusion Enables marked sections of text to be transcluded
LandingCheck Send users to localized landing pages with fallback options
Fundraising tech
LdapAuthentication Provides LDAP authentication, and some authorization functionality
Linter Help users find out-dated bits of wikitext to fix them
Content Transform Team
LiquidThreads A structured discussion system for MediaWiki
Listings For use in imported Wikitravel articles. In the future, tags should be substituted by more powerful ones
LoginNotify Notify users of suspicious logins
Community Tech
MachineVision Interfaces with internal and external machine vision service providers and stores and serves results for usage on-wiki (to be deployed Sept 2019)
Content Transform Team (but probably needs to migrate stewardship) Structured Data team (details and SLA)
MapSources Gives access to several data and mapping sources
MassMessage Allows users to send messages across wikis
Unassigned wctaiwan, Derick Alangi
Math Renders mathematical formulas between <math> ... </math> tags
Editing team Derk-Jan Hartman, Moritz Schubotz
MediaModeration Checks uploaded media for possible child exploitation content. Core Platform Team
MediaSearch An alternative, media-focused way to display search results through the Special:MediaSearch page.
Structured Data team (details and SLA)
MobileApp Serves styles and scripts for use in the Wikimedia native apps
Apps (SLA details), Content Transform Team
MobileFrontend Optimizes content for mobile experiences.
Reading Web (SLA details)
MultimediaViewer Provides a better experience to users when they click on thumbnails in a page
Structured Data team (details and SLA)
NavigationTiming Logs perceived latency measurements from client-side
Performance Team Timo Tijhof
Newsletter Adds a preference for newsletter subscription
Unassigned Brian Wolff (for emergency issues)
NewUserMessage Adds a message to newly created user's talk pages
Growth team
Nuke Gives sysops the ability to mass delete pages
Unassigned Under review

task T221155

Jeroen de Dauw
OATHAuth An HMAC based One Time Password extension, providing two-factor authentication
OAuth Allow users to safely authorize another application (Consumer) to use the MediaWiki api on their behalf
Core Platform Team Tgr (WMF)
OAuthRateLimiter Implements an OAuth hook to add rate limit values to the OAuth JSON Web Token (JWT)
Core Platform Team PPchelko_(WMF), CAndrew_(WMF)
OpenStackManager Provides a web interface based on MediaWiki, offering a Nova or Swift manager that allows authorized users to create and manage projects, instances, IP allocations, DNS and LDAP entries, and boot images, to run virtual servers hosted on an OpenStack cloud.
Wikimedia Cloud Services AndrewBogott (WMF), BDavis (WMF)
ORES Integrates data from the ORES project into the RecentChanges view
Growth team/Scoring Platform team
PageAssessments Stores assessments of pages made by WikiProjects
Community Tech Kaldari
PagedTiffHandler Handles TIFF files, including multi-paged images
Product Infrastructure (SLA details)
PageImages Stores information about images representing a page
Reading Web (SLA details)

Pending stewardship review

PageTriage Facilitates reviewing and approving new pages
Growth team
PageViewInfo Provides fancy looking graphs of Wikimedia page view data
ParserFunctions Enhances parser with logical and string functions
Content Transform Team Jackmcbarn, Tim Starling?
PdfHandler Handles PDF files like multipage DJVU
Product Infrastructure (SLA details) bawolff
Poem Adds <poem> tag for poem formatting
PoolCounter Provides a MediaWiki client for the pool counter daemon
Core Platform Team Platonides
Popups Displays popups when users hover over article links (aka. Hovercards)
Reading Web (SLA details)
ProofreadPage Helps proofreading of books.
(Active volunteer) Thomas PT (Tpt)
PropertySuggester Provides suggested properties when a user tries to add new statements to a Wikidata item.
WMDE Engineering (contact EMs)
QuickSurveys Provides in-article quick surveys or external survey to poll readers for opinions.
Reading Web (SLA details) Consult Reading Web for large architectural changes or UBN bugs.

Others are feel free to contribute and merge changes to this extension.

Quiz Quiz building tool adopted on the Wikiversity
ReadingLists Provides an API for storing and retrieving private lists of pages.
Product Infrastructure (SLA details)
RelatedArticles Parser function to associate related articles (cf. Wikivoyage)
Reading Web (SLA details)
Renameuser Provides a special page that allows user accounts to be renamed
Unassigned Marius Hoch
RevisionSlider Visualizes revision history
WMDE Engineering (contact EMs)
RSS Displays RSS feeds on a wiki page
SandboxLink Provides a link in personal tools to a per-user sandbox
SecureLinkFixer Automatically rewrites URLs to HTTPS if domain always requires HTTPS
Core Platform Team Legoktm
Score Allows rendering of musical scores with en:LilyPond
Editing team Alexander Klauer, Ebe123
Scribunto Provides a framework for embedding scripting languages into MediaWiki pages
Core Platform Team Tim Starling, Victor Vasiliev, Jackmcbarn
SearchExtraNS Searches extra specified namespaces if no direct match is found
SearchVue Vue.js augmentations and improvements to Special:Search
SecurePoll Extension for elections and surveys
ShortUrl Adds a special page that redirects to an article based on the given base36-encoded ID
Unassigned Under review

task T187045

SimilarEditors Adds a special page for discovering editors with similar edit histories
Anti-Harassment Tools Team
SiteMatrix A special page with a matrix of all Wikimedia sites
SpamBlacklist Provides a regex-based spam filter
Unassigned Under review

task T224921

StopForumSpam Blocks write actions based upon deny lists
The Wikimedia Security Team SBassett_(WMF), Reedy, Legoktm
SubPageList3 Provides a splist tag to list the subpages of a page
SubpageSortkey Changes the default sortkey to have something to do with the subpages
Unassigned Brian Wolff
SyntaxHighlight_GeSHi Allows source code to be syntax highlighted on the wiki pages
Editing team
TemplateData Creates and extracts data about templates and their usage
Editing team
TemplateSandbox Enables page previews using sandboxed templates
Unassigned Jackmcbarn
TemplateStyles Allows for loading sanitized CSS stylesheets from a template
Content Transform Team Gergő Tisza
TemplateWizard Adds a popup dialog box for adding template code to wikitext.
Community Tech Samwilson
TextExtracts Provides API with plain-text or limited HTML extracts of page content
Reading Web (SLA details)

Pending stewardship review.

Thanks Lets users thank other users for individual edits
Growth team wctaiwan
TheWikipediaLibrary Notifies users of their eligibility for the Wikipedia Library when they cross the edit count and account age thresholds
Wikipedia Library team Jason Sherman, Susana Cardenas Molinar
TimedMediaHandler Provides integrated support for server side transcoding, WebM, Ogg Theora, Vorbis, Speex and Timed Text
Readers Engineering Brion Vibber (Emergency Backup: Structured Data), Michael Dale
TitleBlacklist Blocks the creation of pages matching a regular expression blacklist
Unassigned Jackmcbarn
TocTree Adds options for floated or expanded table of contents (cf. Wikivoyage)
TorBlock Automatically applies restrictions to Tor exit nodes with access to the wiki's front-door server
Core Platform Team
Translate Enables in-wiki translation and proofreading
Language team
TranslationNotifications Allows translators sign up for translation notifications
Language team
TrustedXFF Handles trusted proxy addresses (XFF)
Core Platform Team
TwoColConflict Provides an interactive two-column edit conflict resolution tool
WMDE Engineering (contact EMs)
UniversalLanguageSelector Allows users to select a language and configure its support in an easy way.
Language team
UploadsLink Provides a link in personal tools to a user's uploads
UploadWizard Helps people upload media to Commons.
Structured Data team (details and SLA) Mark Holmquist
UrlShortener Provides a basic URL shortening service
Core Platform Team
VisualEditor Enables a rich-text editor for wiki pages (see also Parsoid)
Editing team
WebAuthn A module for OATHAuth extension that provides authentication using WebAuthn API
WikibaseClient Client for structured data repository
WMDE Engineering (contact EMs)
WikibaseRepository Structured data repository
WMDE Engineering (contact EMs)
WikibaseCirrusSearch Implements searching for Wikibase repositories using Elasticsearch
Search Platform
WikibaseLexeme Structured lexicographical data
WMDE Engineering (contact EMs)
WikibaseLexemeCirrusSearch Implements searching for Wikibase Lexemes using Elasticsearch
Search Platform
WikibaseMediaInfo Wikibase extension to manage structured metadata of media files
Structured Data team (details and SLA) Specific code for Wikibase as running on WMDE Engineering (contact EMs)
WikidataPageBanner Adds pagewide banners at the top of pages in specified namespaces on a wiki.
Reading Web (SLA details)
WikiEditor Provides an extendable wikitext editing interface and many feature-providing modules
Editing team Derk-Jan Hartman
wikihiero Enables the use of hieroglyphs with additional syntaxes
Unassigned Max Semenik
WikiLove Makes it easy to add positive feedback to user talk pages
WikimediaApiPortalOAuth The WikimediaApiPortalOAuth extension is designed to connect the API Portal with the OAuth server on Meta-Wiki. It provides a user interface to create and manage OAuth 2.0 clients. Core Platform Team
WikimediaBadges Default themes to display badges on Wikimedia projects
WMDE Engineering (contact EMs)
WikimediaEditorTasks Task generation, storage, and API service for microcontribution suggestions
Content Transform Team
WikimediaEvents Event instrumentations and wiring for Wikimedia Foundation sites
Performance Team See file for individual owners of each schema.

Consult with Performance for large changes.

WikimediaIncubator Adds functions meant for Wikimedia Incubator
(Active volunteer) Robin Pepermans, Hydriz, Ebe123
WikimediaMaintenance Various WMF-specific maintenance scripts
Unassigned Sam Reed
WikimediaMessages Adds Wikimedia specific messages and grammar, as well as Wikimedia specific overrides for license related messages
Unassigned Maarten Dammers
Community Tech Tpt
XAnalytics Communicates analytic information for WMF to logging infrastructure

MediaWiki skins deployed at Wikimedia FoundationEdit

See also: Category:Skins used on Wikimedia and phab:source/mediawiki-config/browse/master/wmf-config/extension-list
Not all the areas below actually have their own Phabricator project, or have not had #tags setup for alternate names yet.
Skin Phabricator tag Description Steward Maintainers
Vector #Vector MediaWiki's default skin since 2010; outcome of the Usability Initiative. The Web team does not triage any tasks for Vector tagged with one of: #Responsive-Vector, #Reading-Web-Local-Wiki-Issues, #MediaWiki-Core-Testing. Reading Web (SLA details)
MinervaNeue #MinervaNeue A mobile-first skin for Wikipedia. Reading Web (SLA details)
Timeless #Timeless A fully featured skin that emphasises both content and editing tools. Unassigned Isarra
MonoBook #MonoBook An old skin from 2004, in grey. Reading Web (SLA details) Bartosz Dziewoński
CologneBlue #CologneBlue An old skin from 2002, in blue. Reading Web (SLA details) Bartosz Dziewoński
Modern #Modern An old, unsupported skin from 2008. Reading Web (SLA details)
Nostalgia #Nostalgia An old, unsupported skin that pretends to be UseMod. Only available on Reading Web (SLA details)
WikimediaApiPortal #WikimediaApiPortal WikimediaApiPortal is a skin for MediaWiki created by the Wikimedia Foundation Platform Engineering Team in 2020 as part of the API Gateway initiative. The skin is designed to mimic the look and feel of conventional developer portals by incorporating header and sidebar navigation elements and following the Wikimedia Design Style Guide. The skin uses the Bootstrap CSS framework, OOUI library, and Mustache templates. The skin was created for use with the Wikimedia API Portal, so some elements of the design such as the site logo and footer are specific to Wikimedia. Core Platform Team

Libraries deployed with MediaWiki at Wikimedia FoundationEdit

For upstream libraries that we bundle, see Upstream projects. For other libraries that we publish see (includes developer dependencies, and projects not used by MediaWiki).

MediaWiki core librariesEdit

See also the composer.json and foreign-resources.yaml files in MediaWiki core.

Frontend and backend libraries that are published by Wikimedia and bundled with MediaWiki core.

Library Repository Issue tracker Steward Maintainers Language(s)
cssjanus/cssjanus GitHub GitHub Performance Team Timo Tijhof, Roan Kattouw PHP
oojs Gerrit Phabricator Performance Team Timo Tijhof, Roan Kattouw JS
oojs-ui Gerrit Phabricator Unassigned originally: James Forrester, Bartosz Dziewoński, Volker E. JS, PHP
jquery-client Gerrit Phabricator Performance Team Timo Tijhof JS
oojs-router Gerrit Phabricator Unassigned originally: Jon Robson JS
wikimedia/assert Gerrit TBD Unassigned PHP
wikimedia/at-ease Gerrit Phabricator Performance Team Tim Starling, Legoktm, Timo Tijhof PHP
wikimedia/base-convert Gerrit Phabricator Unassigned PHP
wikimedia/cdb Gerrit Phabricator Performance Team Tim Starling, Timo Tijhof PHP
wikimedia/common-passwords Gerrit Phabricator Unassigned originally: Sam Reed PHP
wikimeda/composer-merge-plugin GitHub GitHub Unassigned originally: Bryan Davis PHP
wikimedia/CLDRPluralRuleParser Gerrit Phabricator Language team Niklas Laxström PHP
wikimedia/html-formatter Gerrit Phabricator Unassigned PHP
wikimedia/ip-set Gerrit Phabricator Unassigned Brandon Black PHP
wikimedia/ip-utils Gerrit Phabricator Unassigned PHP
wikimedia/less.php GitHub GitHub Performance Team Timo Tijhof PHP
wikimedia/minify Gerrit Phabricator Performance Team Timo Tijhof, Roan Kattouw PHP
wikimedia/normalized-exception Gerrit Phabricator Unassigned Gergő Tisza PHP
wikimedia/object-factory Gerrit Phabricator Unassigned PHP
wikimedia/parsoid Gerrit Phabricator Content Transform Team Subbu Sastry, C. Scott Ananian PHP
wikimedia/php-session-serializer Gerrit Phabricator Core Platform Team PHP
wikimedia/purtle Gerrit Phabricator WMDE Stas Malyshev PHP
wikimedia/relpath Gerrit Phabricator Performance Team Timo Tijhof PHP
wikimedia/remex-html Gerrit Phabricator Core Platform Team Tim Starling PHP
wikimedia/request-timeout Gerrit Phabricator Core Platform Team Tim Starling PHP
wikimedia/running-stat Gerrit Phabricator Performance Team PHP
wikimedia/scoped-callback Gerrit Phabricator Performance Team Aaron Schulz PHP
wikimedia/services Gerrit Phabricator Platform Engineering Team Legoktm PHP
wikimedia/utfnormal Gerrit Phabricator Unassigned originally: Brion VIBBER PHP
wikimedia/timestamp Gerrit Phabricator Unassigned PHP
wikimedia/wait-condition-loop Gerrit Phabricator Performance Team Aaron Schulz PHP
wikimedia/wrappedstring Gerrit Phabricator Performance Team Timo Tijhof PHP
wikimedia/xmp-reader Gerrit Phabricator Unassigned PHP

MediaWiki extension libraries deployed at WikimediaEdit

Library Repository Issue tracker Steward Maintainers Language(s)
VisualEditor Gerrit Phabricator Editing team Ed Sanders JS
UnicodeJS Gerrit Phabricator Editing team David Chan,

James Forrester, Ed Sanders

jquery.uls GitHub GitHub Language team Santhosh Thottingal JS
jQuery.IME GitHub GitHub Language team Santhosh Thottingal JS
jQuery.i18n GitHub GitHub Language team Santhosh Thottingal JS
jQuery WebFonts GitHub GitHub Language team Santhosh Thottingal JS
wikimedia/css-sanitizer Gerrit Phabricator Unassigned originally: Gergő Tisza PHP
wikimedia/equivset Gerrit Phabricator Unassigned originally: Brion VIBBER PHP
wikimedia/lucene-explain-parser Gerrit Phabricator Search Platform PHP
wikimedia/textcat Gerrit Phabricator Search Platform Trey Jones PHP
wikimedia/zest-css Gerrit Phabricator Content Transform Team C. Scott Ananian PHP

Upstream projects and librariesEdit

There are many upstream projects on which MediaWiki, extensions, and/or Wikimedia depend. Some of them were "invented here", as stand-along libraries, or split out as part of the Library infrastructure for MediaWiki project. Some of them are widely-used third party tools to which community members provide improvements or support. Others are merely used with gratitude.

Services and administrationEdit

See also: wikitech:Category:Services and m:FLOSS-Exchange

  Note: If you need immediate help with a systems administration question, please go into the IRC channel #wikimedia-operations connect and find the person currently on Ops Clinic duty" (as listed in the /topic).

Not all the areas below actually have their own Phabricator project, or have not had #tags setup for alternate names yet.
Component Description Code Stewards Maintainers
API Gateway The API Gateway is a service that runs in Kubernetes based on Envoy. The service implements many features central to serving the unified API and the API portal. Core Platform Team
Apache configuration Tickets for changes to Wikimedia's apache configuration files (such as project portals, redirects, rewrites etc.). Store in operations/puppet repository. SRE Giuseppe Lavagetto, Luca Toscano, Moritz Muehlenhoff
Backup & data recovery management Backups and recoveries are normally self-served & automated (setting up new backups, generating them, recovering from, but Data Persistence "owns" the setup and maintenance of the infrastructure, and can support people needing help for the centralized setup (using Bacula, MinIO and Python), specially for new, large projects with special needs. SRE > Data Persistence Jaime Crespo
Blog The Wikimedia Blog, a WordPress installation (hosted by, WMF Communications Team
ChangeProp Change propagation Core Platform Team
Citoid Citoid Core Platform Team
Cloud Services Wikimedia Cloud Services computing infrastructure, the Toolforge hosting environment, and many additional supporting technologies used in the Cloud Services environment. Services Introduction Wikimedia Cloud Services team
cxserver cxserver Language team
DNS Issues relating to the nameserver configuration. SRE > Traffic
Databases Administration and troubleshooting of Database servers. SRE > specially (but not only) DBAs. and
Datasets>General All datasets provided by Wikimedia for third-party users to download. WMF Projects/Data Dumps CPT, WMCS, WMDE Engineering (contact EMs) Ariel Glenn, Hydriz
Etherpad Anything related to Wikimedia's installation of Etherpad or Etherpad Lite. and SRE > Service Operations Mark Holmquist, Alexandros Kosiaris, Daniel Zahn
Extension setup New extensions to get installed or enabled. Just like 'Site configuration' but more specific.

See: Category:Extensions used on Wikimedia

Release Engineering (as of 2016-09-21) Sam Reed
Fundraising Misc. A catch-all for miscellaneous fundraising-related components not covered by MediaWiki extensions and civicrm. See: FR Tech
Graphite - a real-time performance graphing system SRE
Git/Gerrit Issues with Wikimedia's installation of Git/Gerrit.


Release Engineering (as of 2016-09-21)
Interwiki links Inter-language and inter-wiki links. This, that and the other
IRCRecentChanges Issues with Recent Changes feeds on IRC cloak/channel requests etc should go to #wikimedia-ops or to meta. See meta:IRC/Cloaks. Data Engineering
IRC Bots Issues with bot tools on Libera or Freenode networks that are not in "WM-Bot" or "Wikibugs". Cloak/channel requests etc should go to #wikimedia-ops or to meta. See meta:IRC/Cloaks. (Active volunteer) Petr Bena
ircservserv Manages IRC channel configuration through declarative files in Git. (Active volunteer) Legoktm, Majavah
Kask Kask is an opaque key-value data store with a RESTful (HTTP) interface. Core Platform Team Core Platform Team
Language setup New languages or fixes to language settings. Unassigned Dereckson
Mailing lists Issues relating to the mailing lists/Mailman.

See: m:Mailing lists/Administration,,

SRE Ladsgroup, Legoktm
Mathoid Mathoid Core Platform Team
Media storage Wikimedia Swift, and other storage infrastructure for images, videos, etc. See: SRE Filippo_Giunchedi, Matthew Vernon
Mobileapps Specially formatted page and feed content for mobile clients. See: mw:Wikimedia Apps/Team/RESTBase services for apps, and (service) Content Transform Team
Icinga SRE
NOC contains public copies of our configuration files. and Unassigned
ORES ORES / Scoring platform team
OTRS Wikimedia's m:OTRS service and setup. SRE > Service Operations User:Madman, Peter Gervai
Parsoid Parsoid Content Transform Team
Phabricator Configuration of Wikimedia's Phabricator installation.


Release Engineering (as of 2016-09-21) Andre Klapper, and administrators
php-excimer Low-overhead sampling profiler and interrupt timer. Performance Team Tim Starling
php-luasandbox Safely execute untrusted Lua 5.1 code. Core Platform Team Tim Starling
php-wikidiff2 Fast diff engine. WMDE Engineering (contact EMs)
php-wmerrors Extended error handling and display. Performance Team Tim Starling, Timo Tijhof
Proton Proton Content Transform Team
Restbase Restbase: Service in front of many other services, i.e. Parsoid, Citoid, Mathoid, Graphoid Core Platform Team
RT - managing the procurement queue. SRE
Shop Wikimedia Store - Unassigned
Site configuration Requests for changes to the MediaWiki configuration of sites hosted by the Wikimedia Foundation. See also the operations/mediawiki-config repository. For the installation of Extensions, use the "Extensions setup" component. Release Engineering (as of 2016-09-21) Sam Reed
SSL related Issues about HTTPS, SSL certificates and HSTS - SRE > Traffic
Statistics The usage statistics at See also meta:Statistics and Analytics/Wikistats Analytics team Diederik van Liere, Erik Zachte
SVG rendering Bugs related to SVG rendering on Wikimedia websites. Unassigned TheDJ?
Continuous integration Bugs relating to Continuous Integration (Running Jenkins and Zuul) Release Engineering (as of 2016-09-21) integration group
Vagrant (mediawiki-vagrant) Virtual environment for bootstrapping MediaWiki development Release Engineering (as of 2016-09-21)
wikibugs IRC bot Announces changes to Phabricator tasks on IRC - Legoktm, Valhallasw
Wikimedia Portals Wikimedia Portals Reading Web JDrewniak
Wikitech wiki Provides documentation related to the technical projects and infrastructure maintained by the Wikimedia Foundation -, Wikimedia Cloud Services team
Zotero translation-server Service that is in support of the citoid service. Editing team

Data EngineeringEdit

Component Repository Issue tracker Steward Maintainers
Event Metrics GitHub Phabricator Data Engineering MusikAnimal, Samwilson, HMonroy
Dashiki Gerrit Phabricator Data Engineering Dan Andrreescu
Wikistats 2 Gerrit Phabricator Data Engineering Dan Andrreescu, Marcel Ruiz Forns
Refinery and Datasets Gerrit Phabricator Data Engineering Data Engineering Team
Hadoop Cluster Gerrit Phabricator Data Engineering Data Engineering Team
Event Platform Gerrit

(multiple; check docs)

Phabricator Data Engineering Andrew Otto

Other areas of focusEdit

(Not all of them fit in current projects.)

See alsoEdit