$ php maintenance/install.php --env-checks --passfile /dev/null
PHP 7.0.19-1 is installed.
Warning: Could not find APCu, XCache or WinCache.
Object caching is not enabled.
Found ImageMagick: /usr/bin/convert.
Image thumbnailing will be enabled if you enable uploads.
Found the Git version control software: /usr/bin/git.
Warning: No --scriptpath specified, using default: /wiki.
Using server URL "/wiki".
Warning: Your default directory for uploads (/home/mah/work/code/mediawiki/core/images/) is not checked for vulnerability
to arbitrary script execution during the CLI install.
Using the intl PECL extension for Unicode normalization.
The environment has been checked.
You can install MediaWiki.
[4f1e8f77cd4e56d533c861a9] [no req]   MediaWiki\Services\ServiceDisabledException from line 340 of /home/mah/work/code/mediawiki/core/includes/services/ServiceContainer.php: Service disabled: DBLoadBalancerFactory
Backtrace:
#0 /home/mah/work/code/mediawiki/core/includes/MediaWikiServices.php(501): MediaWiki\Services\ServiceContainer->getService(string)
#1 /home/mah/work/code/mediawiki/core/maintenance/doMaintenance.php(117): MediaWiki\MediaWikiServices->getDBLoadBalancerFactory()
#2 /home/mah/work/code/mediawiki/core/maintenance/install.php(156): require_once(string)
#3 {main}