$dir = 'pptx/test/compiled';
    $zip_file = 'pptx/test/file.zip';

    // Get real path for our folder
    $rootPath = realpath($dir);

    // Initialize archive object
    $zip = new ZipArchive();
    $zip->open($zip_file, ZipArchive::CREATE | ZipArchive::OVERWRITE);

    // Create recursive directory iterator
    /** @var SplFileInfo[] $files */
    $files = new RecursiveIteratorIterator(
        new RecursiveDirectoryIterator($rootPath),
        RecursiveIteratorIterator::LEAVES_ONLY
    );

    foreach ($files as $name => $file)
    {
        // Skip directories (they would be added automatically)
        if (!$file->isDir())
        {
            // Get real and relative path for current file
            $filePath = $file->getRealPath();
            $relativePath = substr($filePath, strlen($rootPath) + 1);

            // Add current file to archive
            $zip->addFile($filePath, $relativePath);
        }
    }

    // Zip archive will be created only after closing object
    $zip->close();