FastAPI Overview

Modern Python web framework for building APIs with Python 3.7+ that focuses on:

• High performance (ASGI support)
• Automatic API documentation
• Type validation via Python type hints

Key Features

1. ASGI Standard - Native async/await support
2. Automatic Docs - Interactive Swagger UI & ReDoc
3. Data Validation - Built-in Pydantic integration
4. Dependency Injection - Modular component system
5. Security - OAuth2/JWT support out-of-box

Performance

• Comparable to Node.js/Go in benchmarks
• ~300% faster than Flask in TechEmpower tests
• Native support for async endpoints

Basic Usage

from fastapi import FastAPI

app = FastAPI()

@app.get("/items/{item_id}")
async def read_item(item_id: int):
    return {"item_id": item_id, "message": "Hello World"}

Pros/Cons

Alternatives: Flask (simpler), Django REST Framework (batteries-included), Express.js (Node.js)