The Constellation architecture orchestrates the connection between the Pega Infinity Server and the front-end design system that is used to render the application’s user interface with the DX APIs.
Constellation Core is the backbone of the Constellation architecture and contains the PCore and PConnect objects. These objects provide public APIs that connect Constellation Core to a specific implementation of a UI library and the related design system. For example, Pega’s Cosmos design system (built on the React UI library) is the default design system that Constellation connects to the Infinity server.
Bridge layers, such as Nebula, use the public PCore and PConnect APIs to access the Core functionality, which provides access to state management, actions, events, and a higher level of abstraction to the DX APIs. For example, the Nebula layer provides a connection between Constellation Core and Pega's React-based Cosmos design system.
For more information, see Using PCore and PConnect Public APIs.