I think the fairest way is to have a serious conversation with him and offer him a tiny stake based on his contribution which should involve contributions plann

I think the fairest way is to have a serious conversation with him and offer him a tiny stake based on his contribution which should involve contributions planning the startup. But with an option to buy back his stake after a few years. That way your friendship is still good and your friend feels like he at least got something. The easiest way is to just remove his contribution and go on your way. I think you said he never committed code so I don't think he has a strong foundation to stand on if he wants to sue. But this also opens up the possibility of legal fees later. Figure out how much the stake will cost you and compare it to the legal cost if he tries to sue you. Then pick the cheaper of the two.