Cosmic Python: Code Architecture for Production Systems

⚠️ CRITICAL DISTINCTION

Cosmic Python is NOT about system architecture (service boundaries, deployment topology, C4 models—that's the separate architecture skill).

Cosmic Python IS about code structure within a Python module or service: how to organize classes, functions, tests, and dependencies so that code is clean, testable, and maintainable.

When to use Cosmic Python:

• You have a service/module to build (the strategic scope is clear from architecture decisions)
• You need to structure the Python code inside that service with clean layers
• You want to enforce clean code principles, SOLID, and dependency management
• You need comprehensive test coverage organized per layer

This skill pairs with:

• Stream Coding (documentation-first methodology) – Use to plan WHAT to build
• Cosmic Python (this skill) – Use to structure HOW to build the code
• Architecture skill – Use for system-level design (separate scope)