Naming conventions - PEP8

Using well known conventions makes easier for other developers to understand your code and maintain it in the future.

• PEP 8 – Style Guide for Python Code

Namespacing

Use proper namespacing to avoid conflicts with existing packages. It is preferred to put any FreeCAD code in a sub-module of the freecad base namespace.

• Python Modules Documentation
• Python Packaging Namespace Packages Guide

Tooling

Code formatting and linting

• Ruff: (modern and fast)

  Ruff Documentation

• Black

  Black Documentation

  Main FreeCAD repo uses black with --linelength=100 in the pre-commit hook, so if you are submitting code to main, take that into account.

Project management

The modern tooling for python is uv, it replaces pip and manage dependencies, project metadata, virtual environments, etc… and it is 10x faster than pip.

uv Documentation

Typing

Type hints makes the code safer and more easy to maintain and refactor.

• typing cheat sheet

There are many static type checkers:

• mypy (maybe the most common)
• pyright (Microsoft)
• ty (New and fast)

Python versions

Current supported python versions in FreeCAD are 3.10+, but some addons may not work with latest python versions.