Virtual worlds and Web XR technologies offer to both programmers and domain experts nearly unlimited capabilities for creating novel computer-based simulated environments just in a web browser.
*Virtual time* is becoming the new crucial concept of collaborative, immersive virtual learning environments (VLE).
This paper explores the Croquet software architecture, which is known for its radical synchronization system with the notion of virtual time. It is ideal for developing collaborative serverless apps, but a tiny stateless server named reflector, on which Croquet heavily relies on still prevents doing that today. This paper presents the research, that transforms reflector into a peer-to-peer application Luminary, by implementing decentralized virtual time. The case study describes the prototype of a collaborative Rubik's Cube simulator, backed by three robots for kids. Finally showing how learners can easily experiment with augmenting physical reality, by creating fully synchronized, collaborative robots, operating in a P2P network.