I was working on a multiplayer minesweeper game in elixir and react a couple years back to try and get a better understanding of otp.

https://mines.gdf3.com https://github.com/slofurno/minesweepers-ex https://github.com/slofurno/minesweepers-front

Wound up spending most of my time focusing on performance. Large boards (say 4000x4000) naively represented by a map in elixir consumed too much memory and trying to render 16 million dom elements in react didn't fly.

Never got around to basic ui stuff like setting player name and color, but I thought the bots were pretty cool.