PowerServer Web APIs is an ASP.NET Core application compiled from the PowerServer C# solution (which is an ASP.NET Core solution generated when the PowerServer project is built). The PowerServer Web APIs (or simply Web APIs, or PowerServer) contains standard REST/JSON APIs, runtime services, and database providers. It works as the back-end which provides data access and services for the installable cloud application.
PowerServer Web APIs must be compiled and published to a server before it can run. If you select to deploy to IIS or local Kestrel server from the PowerBuilder IDE, PowerServer Web APIs will be automatically compiled, published, and run. If you want to deploy to the other hosting environment (such as Docker, Kubernetes etc.), you can open the PowerServer C# solution in SnapDevelop and publish the ServerAPIs project as needed.