I don't know anything about node.js or websockets but I actually set them up and used them in Jitsi Meet's version of the Excalidraw Backend for its recent whiteboard implementation.

Here's me looking at the websocket traffic (I think): https://youtu.be/4rlffwHUchk?t=1857

I might not fully understand the technicals of it but I got it up and running and use it almost every day! :D Maybe I'll someday understand it.