Introduction

Enable hot reloading to speed up your development speed when working with Flask.

Environment Configuration

The following environment variables need to be set before running the Flask app.

export FLASK_APP=app.py
export FLASK_ENV=development
export FLASK_DEBUG=1
flask run

If everything went well, the following output should be printed to your console

$ flask run
 * Serving Flask app 'app.py'
 * Debug mode: on
WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead.
 * Running on http://127.0.0.1:5000
Press CTRL+C to quit
 * Restarting with stat
 * Debugger is active!

You're looking for * Debug mode: on & * Debugger is active!

Conclusion

With this configuration your workflow should be improved dramatically.