python-fastapi-patterns

FastAPI applications need organized routing, middleware, error handling, and configuration management. This Skill provides reusable patterns for endpoint design, dependency injection, request/response validation with Pydantic, and environment-based configuration—all scaffolded through included templates for rapid, consistent API development.

Dependency injection in FastAPI improves testability and code reuse by decoupling business logic from request handling. This Skill covers DI patterns, Pydantic model validation, and lifespan management, enabling you to inject dependencies cleanly into endpoints and background tasks.

Pydantic v2 models enforce schema validation for all incoming and outgoing data. This Skill demonstrates request/response model patterns, path and query parameter handling, and structured error responses—ensuring type safety and automatic OpenAPI documentation.

Yes. This Skill provides production-ready patterns including structured error handling, middleware configuration, health checks, and logging—alongside router organization and background task management—all integrated with uvicorn and OpenAPI/Swagger for robust async REST APIs.

Use the included fastapi-template and scaffold script to generate consistent endpoint boilerplate. Adapt the template to your domain, and the Skill's patterns for routing, validation, and DI ensure your endpoint follows production standards from the start.

This Skill covers router organization for modular endpoint grouping, middleware patterns for cross-cutting concerns, and lifespan management. These patterns scale cleanly as your API grows and integrate with Pydantic validation and dependency injection.