There is no sitemap and no need for it as Sngine use directly like big social networks Facebook and Twitter
Websites needs sitemap only to help search engine bots to index the website however if the website itself provide a good structure for the search engine bots no needs at all for sitemap 🙂
Directly is accessible for search engines bots and updated automatically and works like a visual sitemap.
You can make your website public from admin panel
Then enable the directory also from admin panel
After that you don’t need any sitemap at all and Search Engines like Bing and Google will able to index your website even better than with sitemap.
Also you can use online services to generate sitemap even you still want it
You can Google it for “generate sitemap from url” and you will find a lot of services like this.
Happy Sngine 🙂