Development policy

The development policy defines how Wikimedia software is developed and maintained. This includes MediaWiki core, the bundled skins and extensions, as well as other skins and extensions that are deployed on Wikimedia Foundation wikis.

Architecture Principles
All Wikimedia engineering endeavors are guided by the Architecture Principles.

External Services
Creation of new external services for adding functionality to MediaWiki should follow the related guidelines.

Deprecation policy
Changes to MediaWiki core that deprecate or remove aspects of the public PHP interface, must follow the Deprecation policy.

Code review
Privileged Gerrit users must follow the Gerrit privilege policy when exercising their +2 rights.

Implementation policies

 * PHP's built in serialization mechanism (the  and   functions) should not be used for data stored (or read from) outside of the current process (RFC T161647). See also the relevant section of the PHP coding convention.