A version of TicTacToe/Noughts and Crosses that runs in the source engine's console
Unzip the release (or download the source code), and place the 'tictactoe' folder into the cfg folder for whichever game you wish to use. That's it!
After installation, using the 'exec tictactoe/2-player' in the console of the given game will start the program. There will be some additional information printed in the console after doing this.
I started making a perfect AI, but ran into some issues, so I'm starting with the 2-player version first.
I don't know if I will ever go back to it but I will update the repo if I ever do.