There are many documentation sources relevant to the Wikidata & Wikibase team.
For user facing Wikibase documentation please see https://www.mediawiki.org/wiki/Wikibase (opens new window).
See: (wmde.github.io/wikidata-wikibase-architecture (opens new window))
In 2020 an initiative was started to create some architecture documentation for both Wikidata and Wikibase.
This documentation is currently work in progress.
# Wikimedia documentation portal
See: (doc.wikimedia.org (opens new window))
The Wikimedia open source documentation portal (opens new window) contains low level docs for many software components hosted on Gerrit.
Most notably for us this includes the versioned in repo doc sites for the Wikibase.git MediaWiki extensions for PHP code (opens new window) and JS code (opens new window).
This also includes a variety of story books for UI components, and you can find more by searching for "Wikibase" on the doc site page.
# MediaWiki documentation for "Users"
See (www.mediawiki.org (opens new window))
A higher "user" facing level of documentation exists on the MediaWiki.org site (opens new window).
This includes a WIP overview of MediaWiki architecture (opens new window), as well as documentation of individual settings and hooks such as $wgDBname (opens new window) and PageMoveComplete (opens new window).
Relevant to Wikidata & Wikibase we have a user facing Wikibase documentation page (opens new window), and documentation pages for individual extensions, such as WikibaseLexeme (opens new window).
# Wikimedia deployments
See: (wikitech.wikimedia.org (opens new window))
Documentation relevant to the Wikimedia deployment of our software primarily lives on WikiTech (opens new window).
This also coveres services provided by the Wikimedia Foundation such as Cloud VPS, Tool Labs and more.
You can find the Wikidata specific hub on the WMDE/Wikidata page (opens new window).
# WMDE's Design System
See WiKit Documentation (opens new window).
Documentation that covers how to use and contribute to WiKit - the Wikidata / Wikibase Design System.
If you are on the team you can also find a variety of resources on the internal Google Drive.