--- layout: default title: "FastAPI" nav_order: 10 has_children: true --- # Tutorial: FastAPI > This tutorial is AI-generated! To learn more, check out [AI Codebase Knowledge Builder](https://github.com/The-Pocket/Tutorial-Codebase-Knowledge) FastAPI[View Repo](https://github.com/fastapi/fastapi/tree/628c34e0cae200564d191c95d7edea78c88c4b5e/fastapi) is a modern, *high-performance* web framework for building APIs with Python. It's designed to be **easy to use**, fast to code, and ready for production. Key features include **automatic data validation** (using Pydantic), **dependency injection**, and **automatic interactive API documentation** (OpenAPI and Swagger UI). ```mermaid flowchart TD A0["FastAPI Application & Routing"] A1["Path Operations & Parameter Declaration"] A2["Data Validation & Serialization (Pydantic)"] A3["Dependency Injection"] A4["OpenAPI & Automatic Docs"] A5["Error Handling"] A6["Security Utilities"] A7["Background Tasks"] A0 -- "Defines Routes for" --> A1 A1 -- "Uses for parameter/body val..." --> A2 A1 -- "Uses Depends() for dependen..." --> A3 A0 -- "Generates API spec for" --> A4 A0 -- "Manages global" --> A5 A3 -- "Injects BackgroundTasks object" --> A7 A6 -- "Uses Depends mechanism (Sec..." --> A3 A6 -- "Raises HTTPException on fai..." --> A5 A4 -- "Reads definitions from" --> A1 A4 -- "Reads Pydantic models for s..." --> A2 A4 -- "Reads security scheme defin..." --> A6 A5 -- "Handles RequestValidationEr..." --> A2 ```