rxi indeed is awesome! Do you know in what language/engine his (her?) tools on itch.io are written? They all have an awesome pixelart look to them and I wonder if (s)he uses lua for them too.
also, just a sidenote which you might already be aware of, a lot of itch.io used to be written in Lua. Check out Moonscript, A language that is like the coffeescript of Lua (https://moonscript.org), and Lapis which is a web framework (https://leafo.net/lapis/) that can use Lua or Moonscript. Itch.io used to be built with both, I don't know if that remains true today.