I have just pushed the GemiNotes source to my tildegit:
https://tildegit.org/odintsoff/GemiNotes
It's a very simple app I made with Python and sqlite with no proper coding standards applied, but hopefully the code would be useful for other people trying to learn more about Gemini and cgi scripts in general.
A running version can be found in the link below. I honestly find it very useful and I actually use it to organize some ideas.
gemini://tilde.club/~odintsoff/notes.gmi
If you make something useful with it, let me know!