Not that I know of. I asked. https://news.ycombinator.com/item?id=29937562 https://news.ycombinator.com/item?id=29937562 I'm aware of unfinished efforts and m

Not that I know of. I asked. https://news.ycombinator.com/item?id=29937562 https://news.ycombinator.com/item?id=29937562 I'm aware of unfinished efforts and mockups, e.g. https://news.ycombinator.com/item?id=17505247 https://news.ycombinator.com/item?id=17505247