Currently hosted on Heroku.
Inspiration comes from Zetamac, which is a single-player mental math game that tests basic addition, subtraction, multiplication, and division. To make it more exciting, this is a multiplayer version of Zetamac where players can play 1v1 against other players. There is also a spectator mode to view ongoing games. Another cool feature is that you can speak your answers instead of typing, which is thanks to annyang.
Socket.io and NodeJS are used for communicating between clients and the server.
Several AWS Lambda functions are chained together with Step Functions to save the game to DynamoDB and update the high score after each game.