Built a real-time multiplayer 3D

Built a real-time multiplayer 3D engine from scratch in Rust (~294K lines): deterministic Rapier3D physics at a fixed 60Hz tick, wgpu PBR rendering to native (Metal/Vulkan/DX12) and WebGPU, and custom netcode over QUIC with delta encoding, client prediction, and rollback reconciliation for 20-player sessions. Games run in a sandboxed Luau VM, safe for untrusted code, identical logic on client and server under a strict determinism contract. One Rust core compiles to web, iOS, Android, and server. Ships with its own simulator, tick-level profiler, and telemetry analyzer.