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FastAPI

FastAPI is a Python framework for building fast APIs with type hints.

What Is FastAPI​

FastAPI uses Python type annotations for validation, documentation, and editor support.

It is commonly used for JSON APIs, backend services, ML endpoints, and internal tools.

How To Use FastAPI​

Define routes with decorators, use type hints for request and response models, and run the app with an ASGI server.

Basic Example​

from fastapi import FastAPI

app = FastAPI()

@app.get("/health")
def health():
    return {"ok": True}

Common Concepts​

  • Path operations define API endpoints.
  • Pydantic models validate data.
  • Dependency injection shares reusable logic.
  • OpenAPI docs are generated automatically.

What To Learn Next​

Learn request models, dependencies, authentication, background tasks, database sessions, and deployment.