The file lib/Wikibase.php used to be the entry point of the WikibaseLib extension. Directly loading this file has not been necessary since the earliest days of Wikibase – it was loaded automatically by the entry points of the Client and Repo extensions. Nevertheless, lines similar to the following found their way into some Wikibase installation instructions:

require_once "$IP/extensions/Wikibase/lib/WikibaseLib.php";

If your LocalSettings.php contains such a line, please remove it. It has not been needed for ages, and soon it will stop working.

This refactoring is part of a project with a twofold objective: (1) decouple the Wikibase Client and Repo as much as possible and establish a long-term strategy for organising the shared logic, and (2) get both Client and Repo to use the standard extension registration mechanism to be loaded. The impact of the project is focused on developers who can now have a clearer view of the code, the modules involved, and their interactions which makes their lives easier. Also, the maintenance of the code is now easier. This is the phabricator board of the project.