Code & Development Solid
python-backend-expert
This skill should be used when the user is writing, reviewing, debugging, or architecting Python backend services (FastAPI + SQLAlchemy 2.0 async + Pydantic v2) or long-running runtime processes (workers, ETL, daemons, CLI tools). Assumes Python 3.13+/3.14; detects installed libraries from pyproject.toml/uv.lock and adapts. Covers async correctness, dependency injection with Annotated[T, Depends], N+1 and MissingGreenlet, lifecycle and graceful shutdown, signals/subprocess/atomic writes, project structure, validation, testing, and AI-generated anti-patterns. Trigger phrases include "critique my FastAPI backend", "why am I getting MissingGreenlet", "is this blocking the event loop", "fix N+1 query", "structure my FastAPI project", "review my Pydantic models", "write a Python worker", "subprocess deadlock", and "process keeps growing in memory". Not for Django or Flask apps, notebooks, or data-science scripts — those stacks have different idioms this skill would misapply.