support for quickly building REST APIs. It is a lightweight abstraction that works with your existing ORM/libraries. Flask-RESTful encourages best practices with minimal setup. If you are familiar with Flask Flask-RESTful provides the fields module and the marshal_with() decorator. Similar to the Django ORM and WTForm, you use the fields module to describe the structure of your response. from flask_restful what data you actually render in your response. With the fields module, you can use whatever objects (ORM models/custom classes/etc.) you want in your resource. fields also lets you format and filter the response