Modern Python 3.12+ development with uv, ruff, and production-ready practices. Routes to specialized skills for frameworks and testing.
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majestic-python
January 24, 2026
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npx add-skill https://github.com/majesticlabs-dev/majestic-marketplace/blob/main/plugins/majestic-python/skills/python-coder/SKILL.md -a claude-code --skill python-coderInstallation paths:
.claude/skills/python-coder/# Python-Coder
Modern Python 3.12+ development patterns.
## Related Skills (Use for Specific Needs)
| Skill | Use When |
|-------|----------|
| `fastapi-coder` | Building FastAPI services |
| `django-coder` | Django web applications |
| `pytest-coder` | Writing comprehensive tests |
| `python-debugger` | Debugging Python code |
## Modern Tooling Quick Reference
### Package Management (uv)
```bash
# Project setup
uv init my-project
uv add fastapi pydantic
uv add --dev pytest ruff mypy
# Run commands
uv run python main.py
uv run pytest
```
### Code Quality (ruff)
```toml
# pyproject.toml
[tool.ruff]
line-length = 100
target-version = "py312"
[tool.ruff.lint]
select = ["E", "F", "I", "UP", "B"]
[tool.ruff.format]
quote-style = "double"
```
### Type Checking (pyright/mypy)
```toml
[tool.pyright]
pythonVersion = "3.12"
typeCheckingMode = "strict"
```
## Python 3.12+ Patterns
### Pattern Matching
```python
match command:
case {"action": "create", "item": item}:
create(item)
case {"action": "delete", "id": int(id)}:
delete(id)
case _:
raise ValueError("Unknown command")
```
### Modern Async
```python
async def fetch_all(urls: list[str]) -> list[dict]:
async with aiohttp.ClientSession() as session:
tasks = [fetch(session, url) for url in urls]
return await asyncio.gather(*tasks)
```
### Type Hints
```python
from typing import TypeVar, Protocol
T = TypeVar("T")
class Repository(Protocol[T]):
def get(self, id: int) -> T | None: ...
def save(self, entity: T) -> T: ...
```
## Behavioral Standards
- PEP 8 + ruff formatting
- Type hints throughout
- Tests with pytest (>90% coverage target)
- Prefer stdlib before external deps
- Comprehensive error handling with custom exceptions