@morganlaco: what's the tech stack here? is it just HTML5 for now without any server code? if yes, maybe the best way for you to implement it [MVP like but good to try] is to use TogetherJS and use their special communication channel to sync the game between clients https://togetherjs.com/docs/#com... (you have the added benefit of adding voice chat and all)
And all the code that you do, can then be re-used to implement your own synching mechanism between players if you feel like you should in the future.
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