public static function up($version = null, $name = 'default', $type = 'app')
	{
		// get the current version info from the config
		$current = \Config::get('migrations.version.'.$type.'.'.$name);

		// get the last migration installed
		$current = empty($current) ? null : end($current);

		// get the available migrations after the current one
		$migrations = static::find_migrations($name, $type, $current, $version);

		// found any?
		if ( ! empty($migrations))
		{
			// if no version was given, only install the next migration
			is_null($version) and $migrations = array(reset($migrations));

			// install migrations found
			return static::run($migrations, $name, $type, 'up');
		}

		// nothing to migrate
		return array();
	}