protected function initializers()
    {
        $initializers = [];
        $initializer_files = $this->loader->find('Config/Initializer/*Initializer.php');
        foreach ($initializer_files as $file) {
            require_once $file->getRealPath();
            $class = $file->getClassName();
            $initializers[] = new $class();
        }

        // sort by priority
        usort($initializers, function ($a, $b) { return $a->getPriority() - $b->getPriority(); });

        // call initializer
        foreach ($initializers as $initializer) {
            $initializer->configure($this);
        }
    }