unity3d server. Node.js or Java?

Question

JavaScript

Hello. I once developed a game in Unity. I attached a JS server to it (node.js + socket.io). And the client was written in C#.
Now I plan to continue development, but I don’t know what to choose. On the Internet, everyone recommends ready-made solutions (Gamesparks, smartfox, photon etc.). But I want to develop my own. To fill a hand, and not to take an open one.
What to choose? Java or JS?
PS
Socket.io for unity - development of an ordinary user. I'm not sure that it can be used with the expectation that if there is an influx of players, then the server will withstand it.
Java is chosen by professional campaigns (GameLoft, supercell etc.)

Answer 1

Knowing the possibilities and nodes and toads, I would choose Java using Netty, in any case, a very serious network highload is written on it.