private function getDefaultOptions()
    {
        // the list of default options if no config is found or specified
        return array(
            self::OPTIONS_KEY_IMAGES => array(
                'vectorface/php5.4',
                'vectorface/php5.5',
                'vectorface/php5.6',
                'vectorface/hhvm'
            ),
            self::OPTIONS_KEY_SYNTAX => true,
            self::OPTIONS_KEY_SYNTAXCOMMAND => 'find /opt/source -type f -name "*.php" !  -path "*/vendor/*" -print0 | xargs -0 -n 1 -P 8 php -l | grep -v "No syntax errors"',
            self::OPTIONS_KEY_UNITTESTS => true,
            self::OPTIONS_KEY_UNITTESTSCOMMAND => '/opt/source/vendor/bin/phpunit',
            self::OPTIONS_KEY_PULL => false,
        );
    }