Skins, such as the default skin Vector, are distributed separately. Drop them into this directory and enable as per the skin's installation instructions. You can find a list of available skins at <https://www.mediawiki.org/wiki/Category:All_skins>, and more information about installing and configuring skins at <https://www.mediawiki.org/wiki/Manual:Skin_configuration>. If you are a developer, you might want to fetch the skin tree in another directory and make a symbolic link: mediawiki/skins$ ln -s ../../skins-trunk/FooBar The default skin Vector can be installed by cloning from Git: git clone https://git.wikimedia.org/git/mediawiki/skins/Vector.git Other skins are also available: https://gerrit.wikimedia.org/r/#/admin/projects/?filter=mediawiki%252Fskins%252F https://git.wikimedia.org/project/mediawiki Please note that under POSIX systems (Linux...), parent of a symbolic path refers to the link source, NOT to the target! You should check the env variable MW_INSTALL_PATH in case the extension is not in the default location. The following code snippet lets you override the default path: $IP = getenv( 'MW_INSTALL_PATH' ); if( $IP === false ) { $IP = __DIR__ . '/../..'; } require_once "$IP/maintenance/Maintenance.php"; // a MediaWiki core file