From the keynote presentation, Apple unveiled the developer inteface to visionOS composed of some flavor of iOS frameworks, brand new Spatial Frameworks, and Spatial Audio Engine on the top of the stack sitting on top of a new Multi-App 3D Engine and Foveated Renderer. The relevant iOS frameworks are the usual suspects of SwiftUI, ARKit, and RealityKit. You'll probably need a relatively recent Mac to run Xcode with the new visionOS Simulator. Apple is introducing a new dev tool in the Reality Composer Pro (accompanying Xcode) to work with 3D models, materials, and sounds. And the claim is that the SDK lands later this month, June!
Go back to part 1 of the series "Programming Augmented Reality.