The game of go implemented in Golang.
Currently this program runs on the command line interactively. Ideally it would run as a daemon and accept GTP (Go Text Protocol) on a known socket.
To run this program for the web, it would probably need to be rewritten in a way that state can be managed on the server side in a persistant way. The single daemon described above would be inefficient in a web context and also would make multiple concurrent games complicated. If websockets would be used for communication after the initial connection, then probably the game could be running in a go routine that would hold the websocket connection.