That's a very interesting way to use GitHub issues. I wonder what sort of problems can arise with vendor lock-in, though.

It's probably better to just make them Markdown inside the directory, you can export the Markdown files (since they're in git) but you can't export issues. Github renders both the same since, well, they're both Markdown.

I was not aware that Steam had changed their policy on sharing sales data. That is great! Are there any other indie devs that have shared the data about their Steam sales in a similar fashion? Better yet, is there a good list of links gathered somewhere for that?