MediaWiki user interface framework

MediaWiki has had several user interface frameworks and design systems over the years. In chronological order from oldest to newest:

Library	Deprecated?	ResourceLoader module name	Years	Type	Notes	Example HTML class
jQuery UI	Yes	jquery.ui	2009–	JS component library with built-in design
OOUI		oojs-ui oojs-ui-core oojs-ui-core.icons oojs-ui-core.styles oojs-ui-toolbars +24 more	2011–present	Themeable JS and PHP component library	Originally designed for Vector / Apex . Later themeable . Now defaulting to Wikimedia UI (below). Uses the custom OOjs library.	oo-ui-widget
Wikimedia UI		Not installed	2012–present	Visual design	Design ideas originated in Agora
MediaWiki UI	Yes	Removal in progress. Remaining: mediawiki.ui.button mediawiki.ui.icon	2013–2017	CSS component library		mw-ui-button
WVUI	Yes	Not installed	2020–2023	Vue component library
Wikit	Yes	Not installed	2020–2023	Vue component library
Codex		@wikimedia/codex codex-styles	2022–present	Design system Visual design Design rules (including tokens) Vue implementation CSS implementation PHP component library (when Codex PHP is finished)		cdx-radio

See also

• Design System Team/History of user-interface libraries and frameworks in MediaWiki
• Design System Team/Server rendering background info
• HTMLForm (2009–present) - Wrapper for PHP component libraries. Supports Codex and OOUI as display format. Formerly supported vform, although all uses of that have been refactored since 2025 and it is now deprecated.