dev/docs/00 INBOX/ai/steamvr-quest-3-design-tree.md

date-created, date-modified

date-created	date-modified
2026-10-20 17:45	2026-10-20 17:52

SteamVR to Meta Quest 3 design tree

Goal

Stream PCVR from Zeus to a Meta Quest 3.

The design must produce a repeatable and diagnosable SteamVR session.

Observed facts

• Zeus runs NixOS with a CachyOS kernel.
• Zeus uses an AMD Radeon RX 9070-series GPU with the amdgpu driver.
• Zeus runs Hyprland on Wayland.
• Zeus has Steam and Gamescope configured.
• SteamVR 2.17.10 is installed.
• SteamVR includes Valve's Linux vrlink driver.
• A previous vrlink session detected the Quest 3 and its Touch controllers.
• That session selected 90 Hz from the Quest's 72, 80, 90, and 120 Hz modes.
• SteamVR setup lacks cap_sys_nice on vrcompositor-launcher.
• NixOS can declare host packages, permissions, services, and diagnostics.
• Steam owns the Quest pairing and SteamVR user settings.
• Zeus connects by Ethernet at 10.23.50.221.
• The local Wi-Fi scan finds the Tracion 5 GHz network at 5220 MHz.
• The scan reports a 1170 Mbit/s link rate.
• The operator has no external tracked devices.

Decision tree

• D1: Host platform commitment — Settled: Linux-native on the current NixOS installation.
  • Linux-native on the current NixOS installation.
    • D2: Transport — Blocked by D1
      • Wireless LAN. — Settled: primary transport.
        • D3: Streaming stack — Settled: SteamVR with its built-in VRLink driver.
          • SteamVR with its built-in VRLink driver.
            • D3a: SteamVR acceptance criteria — Settled: reliable session test.
              • Run a SteamVR game for 30 minutes at 90 Hz.
              • Verify visuals, audio, and Touch controllers.
              • Verify one reconnect.
          • ALVR only after SteamVR fails the agreed acceptance criteria.
        • D4: Wi-Fi topology — Settled: keep the current access point.
          • Keep the current access point.
          • Add a dedicated access point.
          • Use a direct Wi-Fi link.
        • D5: Session performance target — Settled: selectable refresh-rate profiles.
          • Selectable refresh-rate profiles.
            • D5a: Default refresh rate — Settled: 90 Hz.
            • D5b: Included refresh rates — Settled: 72, 80, 90, and 120 Hz.
        • D6: Network isolation — Settled: existing trusted LAN.
          • Existing trusted LAN.
          • Dedicated VR VLAN or SSID.
        • D7: Controller and tracking scope — Settled: Quest Touch controllers only.
          • Quest Touch controllers only.
          • Also support external tracked devices.
        • D8: Launch workflow — Settled: automatic service and headset connection.
          • Start SteamVR when Steam Link connects from the Quest.
        • D9: Diagnostics and recovery — Settled: capture health checks and logs.
          • Capture SteamVR logs and health checks.
          • Recover failed sessions manually.
      • USB tether.
        • D10: USB streaming stack — Blocked by D2
          • ALVR over USB.
          • Meta Quest Link through a Windows installation.
        • D11: USB role — Blocked by D2
          • Primary transport.
          • Fallback transport.
      • Both wireless LAN and USB tether.
        • D12: Primary transport — Blocked by D2
        • D13: Fallback behavior — Blocked by D12
    • D14: System integration — Settled: hybrid configuration.
      • NixOS manages system integration.
      • Steam manages Quest pairing and user settings.
  • Dual-boot or replace NixOS with Windows.
    • D15: Windows streaming stack — Blocked by D1
      • Steam Link.
      • Virtual Desktop.
      • Meta Quest Link or Air Link.
      • ALVR.
    • D16: Windows installation scope — Blocked by D1
      • Dedicated VR installation.
      • General-use Windows installation.
    • D2: Transport — Blocked by D1
  • Keep NixOS and add a separate Windows VR host.
    • D17: Host placement — Blocked by D1
    • D15: Windows streaming stack — Blocked by D17
    • D2: Transport — Blocked by D17

Frontier

None.

Settled decisions

• D1: Host platform commitment — Linux-native on the current NixOS installation.
• D2: Transport — Wireless LAN as the primary transport.
• D4: Wi-Fi topology — Keep the current access point.
• D5: Session performance target — Selectable profiles at 72, 80, 90, and 120 Hz.
• D5a: Default refresh rate — 90 Hz.
• D5b: Included refresh rates — 72, 80, 90, and 120 Hz.
• D6: Network isolation — Existing trusted LAN.
• D7: Controller and tracking scope — Quest Touch controllers only.
• D3: Streaming stack — SteamVR with its built-in VRLink driver.
• D3a: SteamVR acceptance criteria — 30-minute session at 90 Hz, with visuals, audio, Touch controllers, and one reconnect.
• D8: Launch workflow — Start SteamVR when Steam Link connects from the Quest.
• D9: Diagnostics and recovery — Capture health checks and logs. Recover failed sessions manually.
• D14: System integration — NixOS manages system integration. Steam manages Quest pairing and user settings.