Not following all requirements, but you could also just have an RSS feed generated from markdown files you have locally and publish that (using a tool like mdrss).
I made a Python library that can be used to simulate the combined effect of financial patterns (e.g. salary, inflation, investment gains, etc) over time so you can plan your finances better. It's currently on my GitHub and I'm looking for new things to add to it :) https://github.com/TimoKats/pylan
Custom Github action written in Ruby. Checks if version is upgraded when updating the repository. Prevents creating a new release with an outdated version in the code somewhere.