using-python-engineering

# Using Python Engineering

## Overview

This meta-skill routes you to the right Python specialist based on symptoms. Python engineering problems fall into distinct categories that require specialized knowledge. Load this skill when you encounter Python-specific issues but aren't sure which specialized skill to use.

**Core Principle**: Different Python problems require different specialists. Match symptoms to the appropriate specialist skill. Don't guess at solutions—route to the expert.

## When to Use

Load this skill when:
- Working with Python and encountering problems
- User mentions: "Python", "type hints", "mypy", "pytest", "async", "pandas", "numpy", "Textual", "TUI"
- Need to implement Python projects or optimize performance
- Setting up Python tooling or fixing lint warnings
- Debugging Python code or profiling performance
- Building terminal user interfaces with Textual

**Don't use for**: Non-Python languages, algorithm theory (not Python-specific), deployment infrastructure (not Python-specific)

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## How to Access Reference Sheets

**IMPORTANT**: All reference sheets are located in the SAME DIRECTORY as this SKILL.md file.

When this skill is loaded from:
  `skills/using-python-engineering/SKILL.md`

Reference sheets like `systematic-delinting.md` are at:
  `skills/using-python-engineering/systematic-delinting.md`

NOT at:
  `skills/systematic-delinting.md` ← WRONG PATH

When you see a link like `[systematic-delinting.md](systematic-delinting.md)`, read the file from the same directory as this SKILL.md.

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## Routing by Symptom

### Type Errors and Type Hints

**Symptoms - Learning Type Syntax**:
- "How to use type hints?"
- "Python 3.12 type syntax"
- "Generic types"
- "Protocol vs ABC"
- "TypeVar usage"
- "Configure mypy/pyright"

**Route to**: See [modern-syntax-and-types.md](modern-syntax-and-types.md) for comprehensive type system guidance.

**Why**: Learning type hint syntax, patterns, and configuration.

**Symptoms - Fixing Type Errors**: