Git bisect blames https://gerrit.wikimedia.org/r/#/c/311312/
Prior to this everything was working.
[44a8a031f7b7c69894dc52b5] /w/index.php?title=Main_Page InvalidArgumentException from line 70 of C:\git\gerrit\mediawiki\includes\libs\rdbms\database\DatabaseSqlite.php: Need 'dbDirectory' or 'dbFilePath' parameter. Backtrace: #0 C:\git\gerrit\mediawiki\includes\libs\rdbms\database\Database.php(389): DatabaseSqlite->__construct(array) #1 C:\git\gerrit\mediawiki\includes\objectcache\SqlBagOStuff.php(185): Database::factory(string, array) #2 C:\git\gerrit\mediawiki\includes\objectcache\SqlBagOStuff.php(271): SqlBagOStuff->getDB(integer) #3 C:\git\gerrit\mediawiki\includes\objectcache\SqlBagOStuff.php(249): SqlBagOStuff->getMulti(array) #4 C:\git\gerrit\mediawiki\includes\objectcache\SqlBagOStuff.php(245): SqlBagOStuff->getWithToken(string, NULL, integer) #5 C:\git\gerrit\mediawiki\includes\libs\objectcache\CachedBagOStuff.php(56): SqlBagOStuff->doGet(string, integer) #6 C:\git\gerrit\mediawiki\includes\libs\objectcache\BagOStuff.php(183): CachedBagOStuff->doGet(string, integer) #7 C:\git\gerrit\mediawiki\includes\session\SessionManager.php(936): BagOStuff->get(string) #8 C:\git\gerrit\mediawiki\includes\session\SessionInfo.php(150): MediaWiki\Session\SessionManager->generateSessionId() #9 C:\git\gerrit\mediawiki\includes\session\SessionProvider.php(176): MediaWiki\Session\SessionInfo->__construct(integer, array) #10 C:\git\gerrit\mediawiki\includes\session\SessionManager.php(268): MediaWiki\Session\SessionProvider->newSessionInfo(NULL) #11 C:\git\gerrit\mediawiki\includes\session\SessionManager.php(242): MediaWiki\Session\SessionManager->getEmptySessionInternal(WebRequest) #12 C:\git\gerrit\mediawiki\includes\session\SessionManager.php(192): MediaWiki\Session\SessionManager->getEmptySession(WebRequest) #13 C:\git\gerrit\mediawiki\includes\WebRequest.php(735): MediaWiki\Session\SessionManager->getSessionForRequest(WebRequest) #14 C:\git\gerrit\mediawiki\includes\session\SessionManager.php(128): WebRequest->getSession() #15 C:\git\gerrit\mediawiki\includes\Setup.php(759): MediaWiki\Session\SessionManager::getGlobalSession() #16 C:\git\gerrit\mediawiki\includes\WebStart.php(137): require_once(string) #17 C:\git\gerrit\mediawiki\index.php(40): require(string) #18 {main}