In most cases the server code is home rolled, especially for realtime networked games. Handling multiplayer at scale is hard to solve in house, especially for p

In most cases the server code is home rolled, especially for realtime networked games. Handling multiplayer at scale is hard to solve in house, especially for popular titles and that's usually handled by third parties such as Multiplay (https://multiplay.com/about/ https://multiplay.com/about/)