I'm not sure that's correct. My account is very definitely active on GitHub, but you're showing it as available.

https://api.github.com/users/myname shows myname as being active. The "updated_at" field shows 2021-11-16. Unless you're counting a 4-month break as being a "ghost account," there's some error.

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Edit: And, in case you are counting a 4-month break as a "ghost," I looked up the most prolific GitHub user (according to some list), fabpot, and your site is also showing his name as available.

My account is definitely not inactive (I've done multiple pushes to it yesterday and today) and the API you're using confirms I'm active yet it still shows as available on your site. So there's definitely a bug in your code somewhere.

Aside from that though, this is a neat idea. If you can iron out the kinks you should be on to a really good platform here.