Introduction to FastAPI & Setup
Explore what FastAPI is, its advantages, and set up your development environment with Python and Uvicorn.
Introduction to FastAPI & Setup is a free FastAPI Backend Development Bootcamp lesson on CoddyKit — lesson 1 of 4. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the FastAPI Backend Development Bootcamp learning path, one of 4 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Welcome to FastAPI!
FastAPI is a modern, high-speed Python web framework for building APIs. It leans on standard type hints, so you ship robust services fast.
Why Choose FastAPI?
FastAPI wins on speed and DX: built on Starlette and Pydantic, it codes fast, catches bugs early via type hints, and auto-generates interactive docs.
Python 3 & Pip: Your Foundation
FastAPI needs Python 3.7+ and pip. Check your version with python3 --version before you go further.
Isolate Your Projects
Always work inside a virtual environment — an isolated package space per project so different versions never collide. Think clean workspace.
Create Your Virtual Env
Create your virtual environment with python3 -m venv .venv, then activate it. You will see (.venv) in your prompt when it is live.
Install FastAPI & Uvicorn
Install the framework and its server: pip install fastapi "uvicorn[standard]". Uvicorn is the ASGI server that actually runs your async app.
Hello FastAPI World!
Drop this into main.py — a tiny FastAPI app with one root route that returns JSON.
from fastapi import FastAPI
# Create a FastAPI instance
app = FastAPI()
# Define a path operation (GET request to the root URL "/")
@app.get("/")
def read_root():
return {"message": "Hello CoddyKit!"}
Run Your API with Uvicorn
Run it with uvicorn main:app --reload. That points Uvicorn at your app object and auto-restarts on every save. It serves on 127.0.0.1:8000.
Auto-Generated API Docs
FastAPI builds interactive docs for free — Swagger UI at /docs, ReDoc at /redoc. Explore and test your endpoints right in the browser.
Check Your Setup Knowledge
You've learned about setting up FastAPI. Which of the following are TRUE statements about getting started with FastAPI?
Recap: Get Started with FastAPI
Nice work! You set up FastAPI, used a venv, wrote your first endpoint, ran it with Uvicorn, and met the auto-generated docs. Next: building real routes.
Frequently asked questions
Is the “Introduction to FastAPI & Setup” lesson free?
Yes — the full text of “Introduction to FastAPI & Setup” is free to read here on the web, and the FastAPI Backend Development Bootcamp course includes 4 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the FastAPI Backend Development Bootcamp course, upgrade to CoddyKit PRO.
What will I learn in “Introduction to FastAPI & Setup”?
Explore what FastAPI is, its advantages, and set up your development environment with Python and Uvicorn. You practise FastAPI Backend Development Bootcamp with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start FastAPI Backend Development Bootcamp?
No prior experience is required. FastAPI Backend Development Bootcamp on CoddyKit is structured for beginners through advanced learners; this is — lesson 1 of 4, so you can start here or from the beginning and move at your own pace.
How long does the “Introduction to FastAPI & Setup” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this FastAPI Backend Development Bootcamp lesson?
Yes. Every FastAPI Backend Development Bootcamp lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- Introduction to FastAPI & Setup
- Your First API Endpoint
- Path & Query Parameters
- Interactive API Docs with Swagger UI