TicTacToe.cz is an open-source web app with 3 games (at the moment) - Tic Tac Toe, Snake and Tetris. You can play Tic Tac Toe in singleplayer or multiplayer mode.
It is built with Next.js and Firebase. You can check its open GitHub repository;
Clone the repo, install the dependencies and run it.
git clone https://github.com/cibulka/tictactoe cd tictactoe npm install npm run dev
By default, the app will run at http://localhost:3000.
I might be looking for new projects! Check my status on cibulka.codes.
Special thanks to my boyfriend who made the russian, spanish and catalan translation.