For these notes, I'm assuming the reader is reasonably familiar with how cython, python and godot works.

Basic steps to use cython in your godot project:

• Download and install godot-python and make sure python scripts are working in your project:
  • https://github.com/touilleMan/godot-python
• Install Cython in your python environment:
  • cd myproject
  • ./addons/pythonscript/x11-64/bin/python3 -m pip install cython==3.0a5