private static function getBundleContentType(\stdClass $bundle): string
    {
        $mimeType = null;
        switch ($bundle->type) {
            case 'sass':
            case 'scss':
            case 'css':
            case 'stylesheet':
                $mimeType = 'text/css';
                break;
            case 'javascript':
            case 'js':
                $mimeType = 'application/javascript';
                break;
            default:
                if (isset($bundle->files[0])) { // first file in the list determines content-type
                    $firstFileMeta = $bundle->files[0];
                    $mimeType = mime_content_type($firstFileMeta->path);
                }
                break;
        }
        
        return $mimeType;
    }