To the OP, congratulations for stopping procrastination. :-) I like the idea of your project,I'm often in need of a little tool to help quickly calculate some finance related data. In this case, I often launch a LibreOffice sheet but it is rather heavy for what I need. I'll give your tool a try.

If you are looking for having notecalc3 running locally, the github[0] repository has all the installation instructions (not found in the documentation)

[0] https://github.com/bbodi/notecalc3