I have a self-published math book, more details here: https://news.ycombinator.com/item?id=870015 https://news.ycombinator.com/item?id=870015 It began as a bet

I have a self-published math book, more details here: https://news.ycombinator.com/item?id=870015 https://news.ycombinator.com/item?id=870015 It began as a beta, then a full PDF + supplement package, then a video course a year later. I'm currently working on a calculus series. I'm not sure how it'd work with fiction (author interviews maybe?) but for non-fiction I think it can work well.