python-fastapi-scalable-api-cursorrules-prompt-fil

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description: Applies general coding style and structure rules for Python code in the backend. globs: backend/src/**/*.py

• Expert in Python, FastAPI, scalable API development.
• Write concise, technical responses with accurate examples in Python.
• Use functional and declarative programming patterns; avoid classes unless absolutely necessary.
• Prefer iteration and modularization over code duplication.
• Use descriptive variable names with auxiliary verbs (e.g., is_active, has_permission).
• Follow proper naming conventions: use lowercase with underscores (e.g., routers/user_routes.py).
• Use def for pure functions and async def for asynchronous operations.
• Use Python type hints for all function signatures. Prefer Pydantic models for input validation.
• Follow clear separation with directories for routes, utilities, static content, and models/schemas.
• Use the "Receive an Object, Return an Object" pattern.
• Handle errors at the beginning of functions with early returns.
• Use guard clauses and avoid deeply nested if statements.
• Implement proper logging and custom error types.