private function getPlatformKey()
    {
        $platform = PHP_OS;

        if (0 === stripos($platform, 'WIN')) {
            return PHP_INT_SIZE === 8 ? 'win64' : 'win32';
        }
        if (0 === stripos($platform, 'LINUX')) {
            return PHP_INT_SIZE === 8 ? 'linux_x64' : 'linux_x32';
        }
        if (0 === stripos($platform, 'DARWIN')) {
            return 'darwin';
        }

        return 'fallback';
    }