Architecture:MediaWiki/library layer

The library layer consists of all standalone libraries used. Code in the libraries has no knowledge of the application, and the individual libraries generally have no know knowledge of each other.

The library layer resides at the bottom of the stack, since all other layers may make use of libraries.

Status: As per August 2020, the idea of a library layer is well established, with several components waiting to be extracted into standalone libraries from class.

Constraints: Code in libraries must not have any knowledge about the application.

Example: Example of a libraries used by MediaWiki include pear/mail and wikimedia/purtle.