- Wikimedia Code Review - Gerrit, our code review tool and Git repository
- Wikimedia Git Repository Browser using Gitblit
- Wikimedia on GitHub - GitHub mirror of all our Git repos, if you like that kind of thing
- Getting started with Git/Gerrit - Get up and running on Git, Gerrit & Wikimedia Labs
- Data hub - freely available datasets to play with, including all Wikimedia project content :-)
- Lua reference manual - using Lua inside MediaWiki templates
- Gadget kitchen - easy intro to writing JS gadgets
- Wikipedia User Scripts - English Wikipedia's very active and rich community page for organizing work on user scripts
- The notorious Swedish bot
- Pywikibot, for writing bots in Python (optimized for Wikimedia wikis)
- Perl library for writing bots
- MediaWiki API docs
- API invocation without parameters
- API sandbox on MediaWiki.org - the sandbox is installed on all Wikimedia wikis
- API sandbox example: load metadata for an image on Wikimedia Commons
- Wikimedia Tool Labs - environment for running tools, bots, web services
- Tool Labs detailed documentation
- Using OAuth - documentation with example code
- MediaWiki Vagrant
- How to contribute to MediaWiki
- VisualEditor - MediaWiki's rich-text editor
- Flow - MediaWiki's next generation discussion system
- Mobile - Mobile projects, including apps
- MediaWiki extensions - including many third-party ones
- Parsoid - new service for parsing wikitext to an equivalent HTML/RDFa document model
- Public Parsoid web service - currently only reachable via HTTP
- Wikimedia NOC - links to Ganglia, config files, logs, and more
- Wikimedia's main Puppet repository
- Tech presentations, including infrastructure-focused ones