public function saveConfig($group, $environment = '')
    {
        // Path do arquivo
        $path = config_path();

        // Itens
        $items = config($group, []);

        // Nome do arquivo
        $file = (! $environment || ($environment == 'production'))
            ? "{$path}/{$group}.php"
            : "{$path}/{$environment}/{$group}.php";

        // Salvar arquivo
        $code = '<?php' . "\r\n\r\n";
        $code .= 'return ' . var_export($items, true) . ';';
        $this->put($file, $code);
    }