0PricingLogin
Flask Academy · Lesson

Why Not the Built-in Dev Server

Production needs a real WSGI server.

The Server That Got You Here

When you ran flask run, Flask started a tiny built-in server. It was perfect for learning, but it was never meant to face real users. 🚦

It Says So Itself

Notice the warning Flask prints on startup. It literally tells you this is a development server and not for production traffic.

WARNING: This is a development server.
Do not use it in a production deployment.

All lessons in this course

  1. Why Not the Built-in Dev Server
  2. Run Flask Under Gunicorn
  3. Write a Production Dockerfile
  4. Front It with Nginx and Compose
← Back to Flask Academy