RESTful has been the go-to choice of API world. Why another API approach? To support more data-driven applications, to provide more flexibility and ease unnecessary code and calls, to address a wide variety of large-scale development problems, **GraphQL** comes with HTTP, JSON, Versioning, Nullability, Pagination, and Server-side Batching & Caching in mind to make API "Simple yet Powerful". By applying [Graphene-Python](http://graphene-python.org/), a library for building GraphQL APIs in Python easily, this talk will go through the background and challenges of applying GraphQL as the new API service in a restaurant POS (point of sale) system within complex cloud infrastructure in Python. Introduction, testing, and live demo is included for sure.