There isn't much to say here since this is a full application and not a library. It's web based minesweeper, but without any JavaScript. Everything is done server side and the server is stateless.
Some cool things that means.
- Bookmarking a game saves the game.
- Sending another person a link of your game will let them play the exact same game.
- Backspace and forward work.
- Backspace and forward always work.