Four In A Row using boardgame.io, a simple project to demonstrate how to get up and running with boardgame.io. The current version is built using board.gameio 0.32.1.
For further information, see this blog that steps through how to set up such a project. Please note that it was originally written for an earlier version of boardgame.io, and there have since been breaking changes. Please see this commit for the fixes required.