OS

Everything between the hardware and the nOSh runtime: the Linux system image, boot flow, systemd units, device tree overlays, kiosk setup, power idle, coprocessor firmware, update path, and release infrastructure.

Contents

• release-setup.md — release infrastructure / CI/CD for the system image and runtime.
• update-system.md — firmware update path (per adr/ADR-0011). Promoted from the 2026-04-21 research plan.
• local-test-workflow.md — operator-facing: how Josh tests a built .img locally via Pi Imager (real hardware) or QEMU arm64 (no hardware).

Stubs to fill: system-image-build.md, boot-and-systemd.md, device-tree-overlays.md, kiosk-mode.md, power-idle.md, coprocessor-firmware.md. Filed as follow-up tasks at PR merge — see _meta/reorg-2026-04-25.md.

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Related

• device/hardware/ — the metal this image runs on.
• software/runtime/ — the userland binary the system image launches at boot.
• software/api-reference/grammars/coprocessor-protocol.md — Pi ↔ Pico UART contract that the OS must satisfy.
• adr/ADR-0011 — firmware update mechanism.
• adr/ADR-0017 — coprocessor architecture.