RESTful Web services are well established for accessing data from the backend, but REST interfaces have their disadvantages and constraints. That’s why Facebook developed GraphQL as an alternative. In this talk the goals and principles of GraphQL are presented. We will look at GraphQL's Schema Language and its Query Language and play around with the GraphQL API of github. Using an example application we will show how Java can be used to build a GraphQL server which supports queries, mutations and notifications.
