kernel: strip debug info in non-Debug builds

ReleaseSafe kept full DWARF/symtab because nothing set strip on the kernel module, bloating the flashable image to 2.4MB (~1.4MB of which was debug info). Strip for every optimize mode except Debug, so release builds shrink to ~900KB while debug builds keep symbols.
update docs/os-development/README.MD
2026-07-23 02:17:50 +01:00 · 2026-07-23 01:41:47 +01:00 · 2026-07-23 00:25:34 +01:00
54 changed files with 196 additions and 165 deletions
@@ -63,7 +63,7 @@ zig build release-x86-64
 Produces `zig-out/danos-x86-64.iso`, a hybrid ISO that boots flashed raw to a
 USB stick (balenaEtcher, dd) or burned to optical media — see
-[docs/release-iso.md](docs/os-development-guide/release-iso.md). `zig build check-iso-image`
+[docs/release-iso.md](docs/os-development/release-iso.md). `zig build check-iso-image`
 validates it without booting.
 ## Run
@@ -191,6 +191,7 @@ fn addKernel(
            .sanitize_c = .off, // the UBSan runtime needs f128/SSE support we don't provide
            .stack_check = false, // stack-probe calls have no runtime to land in
            .stack_protector = false,
            .strip = optimize != .Debug, // DWARF info doubles the flashable image; keep it only for debug builds
            .imports = &.{
                .{ .name = "boot-handoff", .module = modules.boot_handoff },
                .{ .name = "abi", .module = modules.abi },
@@ -3,102 +3,102 @@
 Notes on how danos boots and draws, written to explain the *why* behind the code
 rather than restate it. Roughly in the order things happen at runtime:
-1. **[efi.md](os-development-guide/efi.md) — EFI / the boot process.** How UEFI firmware finds and
+1. **[efi.md](os-development/efi.md) — EFI / the boot process.** How UEFI firmware finds and
   runs the bootloader, what the loader gathers before `ExitBootServices`, how it
   loads the kernel ELF, and the ABI contract for the jump into the kernel. Start
   here.
-2. **[system-image.md](os-development-guide/system-image.md) — system.img, the boot capsule.** The
+2. **[system-image.md](os-development/system-image.md) — system.img, the boot capsule.** The
   bundled user binaries packed into one file in the initial-ramdisk wire
   format, because one open + one sequential read is the only file I/O shape
   firmware is fast at. The trivial container format, the three artifacts one
   build list derives (tree, manifest, capsule), the loader's three-strategy
   fallback chain, and the capsule's kernel-side life as both the spawn table
   and the read-only `/system` mount.
-3. **[gop.md](os-development-guide/gop.md) — the Graphics Output Protocol.** How UEFI exposes graphics
+3. **[gop.md](os-development/gop.md) — the Graphics Output Protocol.** How UEFI exposes graphics
   modes (unlike fixed VGA modes), how we detect the monitor's native resolution
   from EDID and switch to it, and the pixel formats we accept or reject.
-4. **[framebuffer.md](os-development-guide/framebuffer.md) — the framebuffer.** What the linear
+4. **[framebuffer.md](os-development/framebuffer.md) — the framebuffer.** What the linear
   framebuffer the loader hands over actually is, and what **pitch** (stride)
   means versus width — the detail you have to get right to avoid a skewed image.
-5. **[memory-map.md](os-development-guide/memory-map.md) — the memory map.** How the loader learns what
+5. **[memory-map.md](os-development/memory-map.md) — the memory map.** How the loader learns what
   physical RAM exists and hands it to the kernel in danos's own neutral format,
   rather than leaking UEFI's memory descriptors across the boundary.
-6. **[frame-allocator.md](os-development-guide/frame-allocator.md) — the physical frame allocator.** The
+6. **[frame-allocator.md](os-development/frame-allocator.md) — the physical frame allocator.** The
   bitmap allocator that hands out and reclaims 4 KiB physical frames from that
   map — the primitive page tables and the heap are built on.
-7. **[interrupts.md](os-development-guide/interrupts.md) — interrupts and exceptions.** The GDT, IDT and
+7. **[interrupts.md](os-development/interrupts.md) — interrupts and exceptions.** The GDT, IDT and
   TSS, the exception stubs, and the handler that reports a CPU fault in red instead
   of letting it triple-fault into a silent reset.
-8. **[paging.md](os-development-guide/paging.md) — the kernel's page tables.** Building our own 4-level
+8. **[paging.md](os-development/paging.md) — the kernel's page tables.** Building our own 4-level
   page tables, identity-mapping the low 4 GiB, and switching CR3 off the firmware's
   tables onto ours.
-9. **[device-interrupts.md](device-driver-development-guide/device-interrupts.md) — device interrupts.** The Local
+9. **[device-interrupts.md](device-driver-development/device-interrupts.md) — device interrupts.** The Local
   APIC and its timer — the kernel's first interrupt that is *handled and returned
   from*, giving it a heartbeat.
-10. **[heap.md](os-development-guide/heap.md) — the kernel heap.** A growable free-list allocator built on
+10. **[heap.md](os-development/heap.md) — the kernel heap.** A growable free-list allocator built on
   the VMM, exposed as a `std.mem.Allocator` so std containers work — dynamic
   allocation for the kernel.
-11. **[scheduling.md](os-development-guide/scheduling.md) — the scheduler.** Fixed-priority preemptive
+11. **[scheduling.md](os-development/scheduling.md) — the scheduler.** Fixed-priority preemptive
    multitasking: kernel threads, the context switch, O(1) priority selection, and
    blocking (sleep, wait queues) — the leap to a running system.
-12. **[ipc.md](device-driver-development-guide/ipc.md) — inter-process communication.** Bounded blocking
+12. **[ipc.md](device-driver-development/ipc.md) — inter-process communication.** Bounded blocking
    message-passing channels, then synchronous call/reply between *processes* over
    endpoints — the backbone the microkernel's isolated servers talk over.
-13. **[syscall.md](os-development-guide/syscall.md) — system calls.** How ring 3 asks the kernel for
+13. **[syscall.md](os-development/syscall.md) — system calls.** How ring 3 asks the kernel for
    something: the `syscall`/`sysret` fast path, the trap frame, and why the table is
-    deliberately tiny. The numbers are a **private** ABI — [vdso.md](os-development-guide/vdso.md) designs
+    deliberately tiny. The numbers are a **private** ABI — [vdso.md](os-development/vdso.md) designs
    the public boundary that will hide them.
 14. **[vfs-protocol.md](file-system-development/vfs-protocol.md) — the VFS wire protocol.** The language-neutral
    byte-level spec of the file protocol spoken over IPC: request/reply headers,
    the operation table, mount routing, and the append-only evolution rules — the
    first IPC protocol documented as public ABI.
-15. **[drivers.md](device-driver-development-guide/drivers.md) — writing a driver.** The payoff: a driver is an
+15. **[drivers.md](device-driver-development/drivers.md) — writing a driver.** The payoff: a driver is an
    ordinary ring-3 process that claims a device, maps its registers, and **sleeps
    until its hardware interrupts it**. The claim is the capability; `irq_ack` is the
    unmask.
-16. **[driver-model.md](device-driver-development-guide/driver-model.md) — buses, classes and host controllers.** How
+16. **[driver-model.md](device-driver-development/driver-model.md) — buses, classes and host controllers.** How
    real driver stacks factor into three shapes and how families share code. The
    three primitives it proposed are long since built (M13 capability passing,
    M14 DMA + barriers, M15 MSI), and the driver *contract* on top of them —
    hello, supervision, restart — is built too (device-manager.md, M18).
-17. **[usb-hub.md](device-driver-development-guide/usb-hub.md) — USB hubs.** Built (M22): why hub topology is handled
+17. **[usb-hub.md](device-driver-development/usb-hub.md) — USB hubs.** Built (M22): why hub topology is handled
    *inside* the `usb-xhci-bus` driver rather than a separate hub class driver — a
    device behind a hub is reached by the **controller**, programmed with a route
    string in its slot context — plus the compound-hub reality (a USB 3.0 hub is
    physically two hubs) and detection via the hub's status-change interrupt endpoint.
-18. **[process-management.md](os-development-guide/process-management.md) — process management.** The
+18. **[process-management.md](os-development/process-management.md) — process management.** The
    microkernel's `ps`/`kill`/SIGCHLD: enumerate as a table snapshot, the
    supervision link as the kill authority, and child-exit notifications over the
    same endpoints IRQs arrive on.
-19. **[process-lifecycle.md](os-development-guide/process-lifecycle.md) — the process lifecycle.** Built
+19. **[process-lifecycle.md](os-development/process-lifecycle.md) — the process lifecycle.** Built
    (M17): signals over IPC as the one lifecycle vocabulary every process speaks — the
    POSIX.1-1990 words with message delivery instead of stack hijack, the stable
    `process` module interface, exit reasons, published exit events any stateful
    service can subscribe to (the VFS releasing dead clients' handles), and the two
    iron rules (cleanup is the kernel's job; kill is not a signal).
-20. **[device-manager.md](device-driver-development-guide/device-manager.md) — the device manager.** Built (M18,
+20. **[device-manager.md](device-driver-development/device-manager.md) — the device manager.** Built (M18,
    through the app surface): the
    tree, the matcher, and the supervisor. Tree structure lives in the manager,
    authority stays in the kernel; bus drivers report what they see; drivers are
    restarted through the lifecycle vocabulary — the plan that turns
-    [resilience.md](os-development-guide/resilience.md)'s restart goal into increments.
+    [resilience.md](os-development/resilience.md)'s restart goal into increments.
-21. **[input.md](device-driver-development-guide/input.md) — the input module.** Broadcasting input events (keyboard,
+21. **[input.md](device-driver-development/input.md) — the input module.** Broadcasting input events (keyboard,
    mouse, joystick): why a synchronous rendezvous can't fan out to many listeners, the
    asynchronous `ipc_send` primitive built to fix it, and the per-device subscribe/publish
    service layered on top.
-22. **[display.md](device-driver-development-guide/display.md) — the display service.** The display half of the GUI
+22. **[display.md](device-driver-development/display.md) — the display service.** The display half of the GUI
    track: a user-space compositor that owns the framebuffer, composes a layer stack into
    a double buffer, and presents it. Why GOP and the PCI display device are two views of
    one controller, the device-node + write-combining handoff, and what flicker-free buys
-    that tear-free doesn't. Plan: [display-plan.md](device-driver-development-guide/display-plan.md). **v2** (complete) makes
+    that tear-free doesn't. Plan: [display-plan.md](device-driver-development/display-plan.md). **v2** (complete) makes
    scanout a pluggable backend — GOP floor + a native virtio-gpu driver, hot-attached, with
    runtime mode-set, EDID, fenced vsync presents, and restart re-attach:
-    [display-v2.md](device-driver-development-guide/display-v2.md), plan [display-v2-plan.md](device-driver-development-guide/display-v2-plan.md). Looking
+    [display-v2.md](device-driver-development/display-v2.md), plan [display-v2-plan.md](device-driver-development/display-v2-plan.md). Looking
    further out, three research snapshots survey what a *native* driver for real GPU silicon
-    would take as another `.scanout` backend: [nvidia-gpus.md](device-driver-development-guide/nvidia-gpus.md) (RTX 3060 /
+    would take as another `.scanout` backend: [nvidia-gpus.md](device-driver-development/nvidia-gpus.md) (RTX 3060 /
-    Ampere), [amd-gpus.md](device-driver-development-guide/amd-gpus.md) (RX 6600 / RDNA2), and [intel-igpu.md](device-driver-development-guide/intel-igpu.md)
+    Ampere), [amd-gpus.md](device-driver-development/amd-gpus.md) (RX 6600 / RDNA2), and [intel-igpu.md](device-driver-development/intel-igpu.md)
    (Intel iGPU).
-23. **[halting.md](os-development-guide/halting.md) — halting.** Why a kernel can't just "exit", and
+23. **[halting.md](os-development/halting.md) — halting.** Why a kernel can't just "exit", and
    how `while (true) hlt` parks the CPU safely once there's nothing left to do.
 Start with the north star:
@@ -108,7 +108,7 @@ Start with the north star:
  **resilience** (restartable components). Win condition: runs on the author's PC and
  both Raspberry Pis, ideally with a GUI. Real-time is an option to explore, not a
  requirement. The *why* that shapes everything below.
- **[resilience.md](os-development-guide/resilience.md) — resilience.** A design note (not built yet) on
+- **[resilience.md](os-development/resilience.md) — resilience.** A design note (not built yet) on
  fault isolation + live restart — the reincarnation-server + capability model that
  makes "if I break it, I can restart it" real. danos's core motivation.
 - **[zig-self-hosting.md](zig-self-hosting.md) — running Zig on danos.** A design note
@@ -117,14 +117,14 @@ Start with the north star:
  port to **one seam** (`std.os.danos`), so we build an `os` seam module (→ that seam) plus
  the thin `file-system` module, retire the `posix` shim, and follow a phased path to
  `zig build-exe hello.zig` running on danos — **not** Linux-ABI emulation.
- **[threading.md](os-development-guide/threading.md) — threads, the std-shaped way.** **Built** (M1–M6):
+- **[threading.md](os-development/threading.md) — threads, the std-shaped way.** **Built** (M1–M6):
  the `thread` module's `Thread` mirrors `std.Thread`'s API (spawn/join/detach, Mutex/Condition/
  Semaphore) over a **private** thread ABI — several tasks sharing one address space via
  a `thread_spawn` syscall, futex-backed blocking, address-space refcounting. Why it's the
-  native type and not literal `std.Thread` (the [private ABI](os-development-guide/syscall.md)), and why
+  native type and not literal `std.Thread` (the [private ABI](os-development/syscall.md)), and why
-  threads stay a narrow opt-in against the [resilience](os-development-guide/resilience.md) default. Build
+  threads stay a narrow opt-in against the [resilience](os-development/resilience.md) default. Build
-  plan + gates: [threading-plan.md](os-development-guide/threading-plan.md).
+  plan + gates: [threading-plan.md](os-development/threading-plan.md).
- **[vdso.md](os-development-guide/vdso.md) — the vDSO, the public system-call boundary.** A design note
+- **[vdso.md](os-development/vdso.md) — the vDSO, the public system-call boundary.** A design note
  (not built yet) on keeping `abi.zig` genuinely private: a kernel-supplied, C-ABI
  entry blob mapped into every process as the *only* way into the kernel — so the
  syscall numbers can be renumbered or randomised at will, and Rust/C binaries get a
@@ -137,69 +137,69 @@ Cutting across all of these:
  hardware needed to run danos: minimum specs (UEFI x86-64, ACPI, PCIe ECAM,
  xHCI, ~128 MiB RAM) grounded in what the boot path actually assumes, plus a
  plain-language guide matching Intel/AMD CPU generations by name.
- **[release-iso.md](os-development-guide/release-iso.md) — the release ISO.** The flashable boot
+- **[release-iso.md](os-development/release-iso.md) — the release ISO.** The flashable boot
  media: `zig build release-x86-64` wraps the FAT32 boot volume in a hybrid ISO
  (MBR ESP partition + El Torito EFI entry, one embedded image) that Etcher/dd
  flash to USB or a burner writes to disc — built by an in-repo pure-Python
  tool, like the FAT image itself.
- **[architecture.md](os-development-guide/architecture.md) — the architecture split.** How CPU-specific code is kept
+- **[architecture.md](os-development/architecture.md) — the architecture split.** How CPU-specific code is kept
  behind a build-time `arch` module so the generic kernel never names x86_64,
  leaving room for other systems (e.g. an AArch64 Raspberry Pi) later.
- **[arm.md](os-development-guide/arm.md) — ARM targets.** The Raspberry Pi landscape the arch split is
+- **[arm.md](os-development/arm.md) — ARM targets.** The Raspberry Pi landscape the arch split is
  aiming at: `arm` (32-bit, Pi Zero W) vs `aarch64` (64-bit, Pi 3-5), UEFI vs
  device-tree boot, and what each layer needs.
- **[discovery.md](os-development-guide/discovery.md) — device discovery.** A design note on learning what
+- **[discovery.md](os-development/discovery.md) — device discovery.** A design note on learning what
  hardware exists via ACPI (x86) or device tree (ARM) behind one neutral device model —
  when to build it, and how to keep it architecture-agnostic.
- **[acpi.md](os-development-guide/acpi.md) — finding the ACPI tables.** The concrete x86 locator chain:
+- **[acpi.md](os-development/acpi.md) — finding the ACPI tables.** The concrete x86 locator chain:
  how the loader captures the **RSDP**, hands its physical address across in `BootInformation`,
  and how the platform derives the **RSDT/XSDT** from it and walks the SDTs — plus the
  live event side (the SCI, the power button, GPE/Notify) the ring-3 acpi service runs.
- **[power.md](os-development-guide/power.md) — the power service.** System power as a domain-named
+- **[power.md](os-development/power.md) — the power service.** System power as a domain-named
  service: button/lid/battery events published to subscribers, and init's orderly
-  shutdown composing the [lifecycle](os-development-guide/process-lifecycle.md) stop sequence with an ACPI
+  shutdown composing the [lifecycle](os-development/process-lifecycle.md) stop sequence with an ACPI
  S5 write. Firmware-neutral — a PSCI backend drops in on ARM.
- **[timers.md](os-development-guide/timers.md) — timers and time.** The ring-3 surface for reading the
+- **[timers.md](os-development/timers.md) — timers and time.** The ring-3 surface for reading the
  clock and waiting: why `now()` is a syscall rather than a service, and the one-shot
  timer notification (`timer_bind`) that gives supervisors a timed wait — built on the
-  LAPIC heartbeat and calibrated TSC of [device-interrupts.md](device-driver-development-guide/device-interrupts.md).
+  LAPIC heartbeat and calibrated TSC of [device-interrupts.md](device-driver-development/device-interrupts.md).
- **[smp.md](os-development-guide/smp.md) — multiple cores.** A design/research note on how microkernels
+- **[smp.md](os-development/smp.md) — multiple cores.** A design/research note on how microkernels
  (L4, seL4) handle SMP — big kernel lock vs per-CPU vs multikernel — and how the
  right choice depends on whether danos is chasing real-time or resilience.
 - **[coding-standards.md](coding-standards.md) — coding standards.** The naming rule the
  tree follows: non-acronyms are spelled out in full (`message`, not `msg`), files are
  `kebab-case`, code follows Zig's case conventions, and the handful of exceptions
  (POSIX/C ABI names, `init`/`len`/`ptr`, acronyms).
- **[sysv.md](os-development-guide/sysv.md) — the calling convention.** What "the kernel is SysV" means,
+- **[sysv.md](os-development/sysv.md) — the calling convention.** What "the kernel is SysV" means,
  and why the loader→kernel boundary has to pin it (the RDI-vs-RCX handoff).
 - **[testing.md](testing.md) — testing.** How the kernel is tested by booting it in
  QEMU and asserting on its serial output — reproducibly, and structured so the
  same tests run across architectures.
- **[logging.md](os-development-guide/logging.md) — logging.** The multi-sink diagnostic log (serial,
+- **[logging.md](os-development/logging.md) — logging.** The multi-sink diagnostic log (serial,
  0xE9 debugcon, file later) kept separate from the framebuffer display, plus the
  robustness path: optional framebuffer, POST-code checkpoints, and a persistent
  panic breadcrumb so the kernel survives — and can be diagnosed — with no output.
 ## How the pieces relate
-The boot flow ties them together: UEFI runs the loader ([efi.md](os-development-guide/efi.md)), which
+The boot flow ties them together: UEFI runs the loader ([efi.md](os-development/efi.md)), which
-queries the **GOP** to pick a graphics mode ([gop.md](os-development-guide/gop.md)), hands the kernel a
+queries the **GOP** to pick a graphics mode ([gop.md](os-development/gop.md)), hands the kernel a
-**framebuffer** to draw into ([framebuffer.md](os-development-guide/framebuffer.md)) and a **memory
+**framebuffer** to draw into ([framebuffer.md](os-development/framebuffer.md)) and a **memory
-map** of physical RAM ([memory-map.md](os-development-guide/memory-map.md)); the kernel turns that map
+map** of physical RAM ([memory-map.md](os-development/memory-map.md)); the kernel turns that map
-into a **frame allocator** ([frame-allocator.md](os-development-guide/frame-allocator.md)), installs
+into a **frame allocator** ([frame-allocator.md](os-development/frame-allocator.md)), installs
-its **descriptor tables** so CPU faults are caught ([interrupts.md](os-development-guide/interrupts.md)),
+its **descriptor tables** so CPU faults are caught ([interrupts.md](os-development/interrupts.md)),
-builds its own **page tables** and switches onto them ([paging.md](os-development-guide/paging.md)),
+builds its own **page tables** and switches onto them ([paging.md](os-development/paging.md)),
-brings up the **heap** for dynamic allocation ([heap.md](os-development-guide/heap.md)), starts the
+brings up the **heap** for dynamic allocation ([heap.md](os-development/heap.md)), starts the
-**scheduler** ([scheduling.md](os-development-guide/scheduling.md)) and the **timer** that preempts it
+**scheduler** ([scheduling.md](os-development/scheduling.md)) and the **timer** that preempts it
-([device-interrupts.md](device-driver-development-guide/device-interrupts.md)) — with tasks blocking, sleeping and
+([device-interrupts.md](device-driver-development/device-interrupts.md)) — with tasks blocking, sleeping and
-passing messages over **[IPC](device-driver-development-guide/ipc.md)** channels — runs, its CPU-specific bits
+passing messages over **[IPC](device-driver-development/ipc.md)** channels — runs, its CPU-specific bits
-behind the [architecture](os-development-guide/architecture.md) boundary, and when idle, or on a panic, it **halts**
+behind the [architecture](os-development/architecture.md) boundary, and when idle, or on a panic, it **halts**
-([halting.md](os-development-guide/halting.md)).
+([halting.md](os-development/halting.md)).
-Above that line the microkernel proper begins: **discovery** ([discovery.md](os-development-guide/discovery.md),
+Above that line the microkernel proper begins: **discovery** ([discovery.md](os-development/discovery.md),
-[acpi.md](os-development-guide/acpi.md)) learns what hardware exists, ring-3 processes ask the kernel for
+[acpi.md](os-development/acpi.md)) learns what hardware exists, ring-3 processes ask the kernel for
-things through the small **[syscall](os-development-guide/syscall.md)** table, isolated servers reach each
+things through the small **[syscall](os-development/syscall.md)** table, isolated servers reach each
-other over IPC **endpoints** ([ipc.md](device-driver-development-guide/ipc.md)), and a **[driver](device-driver-development-guide/drivers.md)** claims
+other over IPC **endpoints** ([ipc.md](device-driver-development/ipc.md)), and a **[driver](device-driver-development/drivers.md)** claims
 a device, maps its registers, and sleeps until the hardware interrupts it — which is
 the whole reason for the arrangement ([vision.md](vision.md)).
@@ -1,6 +1,6 @@
 # Device interrupts
-CPU exceptions ([interrupts.md](../os-development-guide/interrupts.md)) are the kernel reacting to its own
+CPU exceptions ([interrupts.md](../os-development/interrupts.md)) are the kernel reacting to its own
 mistakes. **Device interrupts** are the opposite: hardware asking for attention —
 a timer firing, a key pressed, a packet arriving. They share the IDT, but differ
 in one fundamental way: an exception here is terminal (we report and halt), while a
@@ -10,7 +10,7 @@ back — the same mechanism a scheduler will later use to preempt tasks.
 The first device we bring up is the **timer**, because it's the simplest: it lives
 entirely on the CPU's local interrupt controller, needing no external routing.
-It's all x86_64-specific, behind the [architecture](../os-development-guide/architecture.md) boundary.
+It's all x86_64-specific, behind the [architecture](../os-development/architecture.md) boundary.
 ## The APIC, not the PIC
@@ -53,7 +53,7 @@ a missing PIT would hang the boot):
 1. **CPUID leaf 0x15** — the CPU's TSC frequency directly, needing no external timer
   at all (the LAPIC is then measured against the TSC).
-2. The **HPET**, discovered via ACPI (see [discovery](../os-development-guide/discovery.md) / [acpi](../os-development-guide/acpi.md)).
+2. The **HPET**, discovered via ACPI (see [discovery](../os-development/discovery.md) / [acpi](../os-development/acpi.md)).
 3. The **ACPI PM timer** (a fixed 3.579545 MHz counter from the FADT).
 4. The **PIT** (legacy 8254, 1.193182 MHz) — last resort, and bounded so it can't hang.
@@ -100,7 +100,7 @@ values (a second socket, some firmware), so a thread migrating from a core readi
 check** as each application processor comes online (`checkWarpSource`, adapted from
 Linux's): the waking core and the BSP hammer a shared "highest seen" TSC under a lock,
 and if either ever reads below it, the cores' TSCs are skewed. It's pairwise because APs
-come up one at a time ([smp.md](../os-development-guide/smp.md)).
+come up one at a time ([smp.md](../os-development/smp.md)).
 **The fallback.** When the TSC fails either test — non-invariant (a bare VM such as the
 default qemu64), or warped between cores — danos moves the monotonic clock onto the
@@ -160,7 +160,7 @@ A device handler is a plain `fn () void` — a timer or keyboard handler doesn't
 the interrupted registers. (The stubs originally didn't save the SSE/vector
 registers, so a handler couldn't use them; `isr_common` now does an
 `fxsave`/`fxrstor` of the full SSE/x87 state around dispatch — see
-[interrupts.md](../os-development-guide/interrupts.md).)
+[interrupts.md](../os-development/interrupts.md).)
 ## Turning them on
@@ -168,7 +168,7 @@ Exceptions can't be masked, which is why they worked all along. Maskable device
 interrupts don't fire until the CPU's interrupt flag is set — so the final step is
 `sti` (`arch.enableInterrupts()`), after the APIC and timer are configured. From
 that instant the kernel has a heartbeat, and its idle `hlt` loop
-([halting.md](../os-development-guide/halting.md)) wakes on every tick and dozes off again.
+([halting.md](../os-development/halting.md)) wakes on every tick and dozes off again.
 ## Verifying it
@@ -188,13 +188,13 @@ spinning in unrelated code — is the whole mechanism working end to end.
 ## Since (done elsewhere)
 - **Preemption**: the timer handler is where the scheduler decides to switch — the
-  reason a *returning* interrupt matters. See [scheduling.md](../os-development-guide/scheduling.md).
+  reason a *returning* interrupt matters. See [scheduling.md](../os-development/scheduling.md).
 - **`sleep()` / timeouts** built on the calibrated clock.
 - **The I/O APIC, routed**: external device lines now reach a vector, and the
  interrupt is delivered onward to a *user-space* driver as an IPC message. See
  [drivers.md](drivers.md).
 - **Uncacheable MMIO**: device grants are mapped `PCD|PWT` (strong-uncacheable) for
-  user drivers — see [paging.md](../os-development-guide/paging.md).
+  user drivers — see [paging.md](../os-development/paging.md).
 ## What's next (partly done since)
@@ -10,18 +10,18 @@ mirrors them and prunes a dead reporter's children, and the `usb-report`
 scenario proves report → prune → respawn → re-report. The application surface is built (M18.3, 2026-07-13):
 `enumerate` and `subscribe` over IPC, with `device-list` as the first client —
 the manager is now the one answer to "what devices exist" for applications.
-The primitives underneath are real ([process-management.md](../os-development-guide/process-management.md):
+The primitives underneath are real ([process-management.md](../os-development/process-management.md):
 spawn/supervise/kill/exit-notification; [driver-model.md](driver-model.md): the device
 table as a capability system; [drivers.md](drivers.md): claim/map/IRQ), and the first
 per-device driver spawn works (the device manager matches the xHCI controller by PCI
 class and spawns `usb-xhci-bus` with the device id as argv[1]). This document designs
 the rest: the device manager as **the tree, the matcher, and the supervisor** — the
-policy process that turns [resilience.md](../os-development-guide/resilience.md)'s restart goal into practice
+policy process that turns [resilience.md](../os-development/resilience.md)'s restart goal into practice
 for drivers.
 How processes stop, reload, and report their deaths is deliberately **not** in this
 document: that is the universal lifecycle every danos process speaks —
-[process-lifecycle.md](../os-development-guide/process-lifecycle.md), signals over IPC and the stable
+[process-lifecycle.md](../os-development/process-lifecycle.md), signals over IPC and the stable
 `process` interface. The device manager is that design's first serious
 customer, not its owner. Its own protocol contains nothing lifecycle-shaped; a
 driver is stopped, health-checked, and buried exactly like any other process.
@@ -35,7 +35,7 @@ The device tree is two things fused: *information* (what exists, how it nests) a
  claims, resource containment on `device_register`, the
  `mmio_map`/`irq_bind`/`msi_bind` gates — and **cleans all of it up when a process
  dies** (settled; it is increment 1 of
-  [process-lifecycle.md](../os-development-guide/process-lifecycle.md)). The three invariants in
+  [process-lifecycle.md](../os-development/process-lifecycle.md)). The three invariants in
  [driver-model.md](driver-model.md) stay exactly where they are. A device manager
  that could mint MMIO mappings by its own say-so would be a second kernel, and a
  buggy one would un-earn everything the microkernel bought.
@@ -51,7 +51,7 @@ enumeration is a **pci-bus driver**: the manager spawns it against the host brid
 like any bus reports children. ACPI becomes an **acpi service** that interprets the
 tables and reports the namespace. The manager only orchestrates and merges. Moving
 AML interpretation out of ring 0 is its own project on its own track; nothing here
-depends on when it lands. (It landed: [discovery.md](../os-development-guide/discovery.md), M19–M20.)
+depends on when it lands. (It landed: [discovery.md](../os-development/discovery.md), M19–M20.)
 `device_register` is **idempotent on exact match**: a re-registration with an
 identical (parent, class, identity, resources) tuple returns the existing id
@@ -82,7 +82,7 @@ one world.
 deadline means wrong binary, wrong protocol version, or wedged before main — apply
 the stop sequence and the restart policy. Everything else lifecycle-shaped
 (terminate, the common `ping` liveness call, exit reasons) arrives through
-[process-lifecycle.md](../os-development-guide/process-lifecycle.md)'s vocabulary, not this protocol.
+[process-lifecycle.md](../os-development/process-lifecycle.md)'s vocabulary, not this protocol.
 Assignment stays argv (`usb-xhci-bus <device id>`) for now — simple, and it works.
 The step after `hello` exists is delegation: the manager claims (or is granted) the
@@ -97,7 +97,7 @@ from usb-ids.zig — each bus's native language, decoded by the shared ids modul
 Every driver is spawned with the manager's exit endpoint (`spawnSupervised` — built).
 On a death notification:
-1. **Read the reason** ([process-lifecycle.md](../os-development-guide/process-lifecycle.md) increment 2).
+1. **Read the reason** ([process-lifecycle.md](../os-development/process-lifecycle.md) increment 2).
   Clean exit → it meant to; don't restart. Fault or missed `hello` deadline →
   restart with **backoff**, and a crash-loop cap (three fast deaths → mark failed,
   stop respawning, log loudly; a later `reload` to the manager can retry).
@@ -136,7 +136,7 @@ way.
 ## Increments
 Increments 1–4 are the lifecycle prerequisites and live in
-[process-lifecycle.md](../os-development-guide/process-lifecycle.md) (claim cleanup on death, exit reasons,
+[process-lifecycle.md](../os-development/process-lifecycle.md) (claim cleanup on death, exit reasons,
 published exit events, signals + `process`). On top of those:
 5. **device-manager-protocol**: `hello`, supervised spawn with restart policy;
@@ -147,7 +147,7 @@ published exit events, signals + `process`). On top of those:
   to a manager-internal seam.
 8. **Discovery migration** — DONE (M19–M20, 2026-07-13): enumeration moved to
   ring 3 as swappable per-firmware discoverers — the pci-bus driver (M19) then
-   the acpi service (M20), see [discovery.md](../os-development-guide/discovery.md); of the enumerable
+   the acpi service (M20), see [discovery.md](../os-development/discovery.md); of the enumerable
   devices, the kernel seeds only the host bridge and the acpi-tables node (the
   non-enumerable platform nodes — processors, interrupt controllers, the HPET,
   the loader's framebuffer — stay kernel-seeded too). Matching moved with it:
@@ -144,4 +144,4 @@ path in VMs**, where danos development happens. The framebuffer floor never goes
 - [display.md](display.md) — v1: the compositor, the GOP-vs-device split, the WC discipline.
 - [display-v2-plan.md](display-v2-plan.md) — the ordered build-out.
 - [driver-model.md](driver-model.md) — claim / `mmio_map` / MSI / capability passing (M13).
- [resilience.md](../os-development-guide/resilience.md) — the restart machinery the hot-attach leans on.
+- [resilience.md](../os-development/resilience.md) — the restart machinery the hot-attach leans on.
@@ -1,6 +1,6 @@
 # The display service: a framebuffer compositor
-The [framebuffer](../os-development-guide/framebuffer.md) the loader hands over is a flat block of pixel
+The [framebuffer](../os-development/framebuffer.md) the loader hands over is a flat block of pixel
 memory, and the kernel's [bootstrap console](../../system/kernel/console.zig) draws text
 into it directly. That console is a stop-gap. The **display service**
 (`system/services/display/`) is the real thing: an ordinary ring-3 process that *owns*
@@ -22,7 +22,7 @@ which one you're holding decides what you can do.
  linear framebuffer pointer and can set video modes — but only until
  `ExitBootServices`. The loader already leans on this: [`queryFramebuffer`](../../boot/efi.zig)
  reads the monitor's EDID, picks the native mode, and calls `set_mode` **before**
-  exiting ([gop.md](../os-development-guide/gop.md)). Once the kernel runs, GOP is **gone** — no `set_mode`, no
+  exiting ([gop.md](../os-development/gop.md)). Once the kernel runs, GOP is **gone** — no `set_mode`, no
  mode list, no EDID. What survives is the frozen snapshot in
  [`BootInformation.framebuffer`](../../system/boot-handoff.zig): `{base, width, height,
  pitch, format, refresh_hz}`, and nothing more.
@@ -66,7 +66,7 @@ rest of the system hasn't had to face:
   [`console.zig`](../../system/kernel/console.zig). It is *not* a
   [devices-broker](../../system/kernel/devices-broker.zig) node, so
   `device.claim`/`mmio_map` cannot reach it, and there is no framebuffer
-   [syscall](../os-development-guide/syscall.md). A user-space display service needs a **new mechanism just to
+   [syscall](../os-development/syscall.md). A user-space display service needs a **new mechanism just to
   touch the pixels**. (See "The handoff" below — this is built.)
 2. **danos had no cross-process shared memory.** At v1 the memory syscalls were `mmap`
@@ -119,7 +119,7 @@ second backend or a second monitor appears; until then it is complexity with no
 The framebuffer crosses into user space through the machinery that already exists for
 every other device, rather than a bespoke syscall — so it inherits ownership,
-release-on-death, and re-claim-on-restart for free (the [resilience](../os-development-guide/resilience.md)
+release-on-death, and re-claim-on-restart for free (the [resilience](../os-development/resilience.md)
 story: a crashed display service returns the LFB to the kernel, and its restart
 re-claims it).
@@ -160,8 +160,8 @@ Two buffers, with deliberately different memory types:
 So a frame is: compose every dirty layer into the cacheable back buffer, then **present**
 — copy the changed regions back→front in sequential, WC-friendly writes. Two details the
-[framebuffer](../os-development-guide/framebuffer.md) note already establishes carry over: step rows by `pitch`,
+[framebuffer](../os-development/framebuffer.md) note already establishes carry over: step rows by `pitch`,
-not `width*4`; and handle both `rgbx` and `bgrx` [pixel formats](../os-development-guide/gop.md).
+not `width*4`; and handle both `rgbx` and `bgrx` [pixel formats](../os-development/gop.md).
 ## Flicker vs. tearing — what double buffering does and doesn't buy
@@ -234,7 +234,7 @@ client module, as with every other danos service.
 The compositor is the single owner of the framebuffer — only the main `service.run` loop
 touches the backend and the layer stack. Tracking the mouse without breaking that
-ownership is the display's first use of [threads](../os-development-guide/threading.md): the service is built
+ownership is the display's first use of [threads](../os-development/threading.md): the service is built
 multi-threaded (`addThreadedUserBinary`) and, at startup, spawns a **mouse-listener
 thread** beside the compositor loop.
@@ -242,7 +242,7 @@ thread** beside the compositor loop.
  (`input.subscribeMouse()`), accumulates the relative `dx`/`dy` motion into an absolute
  cursor position clamped to the screen, and hands it to the compositor. It never touches
  the compositor — so no lock guards the framebuffer. A parked `next()` leaves its core
-  free to halt ([halting.md](../os-development-guide/halting.md)).
+  free to halt ([halting.md](../os-development/halting.md)).
 - **The channel.** A single-slot *latest-value* cell (`CursorChannel`) guarded by a
  `Thread.Mutex`: the renderer wants where the cursor *is now*, not a replay of
  every delta, so a new position overwrites the old. The listener also **pokes** the
@@ -254,13 +254,13 @@ thread** beside the compositor loop.
  which is just a top-z compositor layer — with the existing `configure` + `present` path
  (it damages the old and new footprints, so only those two rectangles repaint).
-Two threading facts shape this (both in [threading.md](../os-development-guide/threading.md)). IPC **handles do
+Two threading facts shape this (both in [threading.md](../os-development/threading.md)). IPC **handles do
 not cross threads**, so the listener can't reuse the main loop's endpoint handle — it
 `ipc.lookup(.display)`s its *own* handle to the same endpoint to poke through. And a
 multi-threaded service doing concurrent IPC is why the kernel's endpoint-create / register
 / lookup syscalls now serialize under the big kernel lock. Shared fate applies: a fault in
 the listener takes the whole display down, and the supervisor restarts the process
-([resilience.md](../os-development-guide/resilience.md)).
+([resilience.md](../os-development/resilience.md)).
 ## What v1 does not do (and why that's fine)
@@ -317,8 +317,8 @@ packing are additionally covered by pure host unit tests under `zig build test`.
 ## See also
- [framebuffer.md](../os-development-guide/framebuffer.md) — the linear framebuffer, pitch vs. width, `volatile`.
+- [framebuffer.md](../os-development/framebuffer.md) — the linear framebuffer, pitch vs. width, `volatile`.
- [gop.md](../os-development-guide/gop.md) — GOP, and why only linear RGBX/BGRX modes are paintable.
+- [gop.md](../os-development/gop.md) — GOP, and why only linear RGBX/BGRX modes are paintable.
 - [input.md](input.md) — the sibling service; the async `ipc_send` fan-out.
 - [driver-model.md](driver-model.md) — claim / `mmio_map`, capability passing, the trust model.
 - [device-manager.md](device-manager.md) — matching and supervision (the native backend's route).
@@ -34,7 +34,7 @@ plain bus driver with no controller — a USB hub — is also a real thing.
 danos already has the right central structure. `system/kernel/devices-broker.zig` holds a table of
 `DeviceDescriptor`, each with a parent, a class, and a set of resources. Firmware discovery
-seeds it ([discovery.md](../os-development-guide/discovery.md)); `device_register` grows it.
+seeds it ([discovery.md](../os-development/discovery.md)); `device_register` grows it.
 Three invariants make it a capability system rather than a directory:
@@ -199,7 +199,7 @@ class driver, the device manager, or the kernel may share them freely.
  `system_spawn(name, arguments)` loads a binary bundled in the initial-ramdisk as a
  fresh ring-3 process; `name` becomes the child's argv[0] and the optional
  NUL-separated `arguments` blob its argv[1..], delivered on a SysV entry stack
-  ([sysv.md](../os-development-guide/sysv.md)). This is what
+  ([sysv.md](../os-development/sysv.md)). This is what
  turned the device manager from "log the match" into "run the driver": the kernel now
  spawns only `init`, `init` spawns the services, and the **device-manager** discovers
  the hardware and spawns each driver ([drivers.md](drivers.md)). Ungated for now — a
@@ -398,6 +398,6 @@ from hand-rolling `*volatile` and getting ARM wrong.
 ## See also
 - [drivers.md](drivers.md) — how to write one, concretely.
- [discovery.md](../os-development-guide/discovery.md) / [acpi.md](../os-development-guide/acpi.md) — where the device table comes from.
+- [discovery.md](../os-development/discovery.md) / [acpi.md](../os-development/acpi.md) — where the device table comes from.
 - [ipc.md](ipc.md) — endpoints, badges, and the notification path an IRQ arrives on.
- [resilience.md](../os-development-guide/resilience.md) — restart, the reason any of this is worth the trouble.
+- [resilience.md](../os-development/resilience.md) — restart, the reason any of this is worth the trouble.
@@ -4,13 +4,13 @@ In a monolithic kernel a driver is a function call away from everything: it runs
 ring 0, dereferences any physical address, and its interrupt handler *is* the ISR. In
 danos a driver is **an ordinary ring-3 process**. It has its own address space, it
 can crash without taking the kernel with it, and — the point of this document — it
-can be restarted ([resilience](../os-development-guide/resilience.md)).
+can be restarted ([resilience](../os-development/resilience.md)).
 That leaves three questions the kernel has to answer, because a process can't answer
 them for itself:
 1. **What hardware exists?** → `device_enumerate`, over the device table discovery built
-   ([discovery](../os-development-guide/discovery.md), [acpi](../os-development-guide/acpi.md)).
+   ([discovery](../os-development/discovery.md), [acpi](../os-development/acpi.md)).
 2. **How do I touch its registers?** → `device_claim` + `mmio_map`: the kernel maps the
   device's physical MMIO window into your address space, and from then on it's plain
   memory. No syscall per register access.
@@ -51,7 +51,7 @@ the optional arguments its argv[1..], on a SysV entry stack, see sysv.md). Every
  is the **driver supervisor**. It does the three steps a monolithic kernel would do in
  its probe path, entirely from ring 3:
  1. **Discover** — `device_enumerate` snapshots the device table the kernel built from
-     ACPI/PCI ([discovery](../os-development-guide/discovery.md)).
+     ACPI/PCI ([discovery](../os-development/discovery.md)).
  2. **Match** — for each device it looks up a driver. The match policy is code, a few
     small per-bus tables: from the boot snapshot only the PCI host bridge matches
     (→ `pci-bus`); everything else arrives later as bus reports and matches on
@@ -293,7 +293,7 @@ the device's `io_port` resource — direct ring-3 `in`/`out` is still a #GP, so
 uncacheable, physical address exposed), **memory barriers** (`library/device/mmio`'s
 `memoryBarrier`/`readMemoryBarrier`/`writeMemoryBarrier`, imported as the `mmio` module), **fault isolation** (a ring-3 fault kills only the faulting
 process — `killCurrentProcess` — and the machine keeps running,
-[resilience](../os-development-guide/resilience.md)), and **reclaim + restart on death** (every path out of a
+[resilience](../os-development/resilience.md)), and **reclaim + restart on death** (every path out of a
 process releases its claims and IRQ/MSI bindings — `releaseAllOwnedBy`,
 `irq.releaseOwner` — and the device manager respawns the driver with backoff,
 [device-manager.md](device-manager.md)). What remains:
@@ -394,7 +394,7 @@ Claiming and mapping is half of being a danos driver; the other half is the
 - Build on `service.run` — one replyWait loop folding protocol
  requests, signals, and notifications into callbacks. The harness answers the
  universal zero-length ping and turns `terminate` into a clean exit for you
-  ([process-lifecycle.md](../os-development-guide/process-lifecycle.md)).
+  ([process-lifecycle.md](../os-development/process-lifecycle.md)).
 - A driver spawned with an assignment (its device id as argv[1]) sends the
  versioned `hello` to the device manager inside the deadline, and a **bus**
  driver reports what it discovers with `child_added`
@@ -160,5 +160,5 @@ serial line names the class received, so the log shows all three arriving on one
 ## See also
 - [ipc.md](ipc.md) — the synchronous rendezvous and the notification path `ipc_send` extends.
- [syscall.md](../os-development-guide/syscall.md) — the system-call surface, including `ipc_send`.
+- [syscall.md](../os-development/syscall.md) — the system-call surface, including `ipc_send`.
 - [driver-model.md](driver-model.md) — class drivers, capability passing (M13), the trust model.
@@ -18,7 +18,7 @@ There are two layers, built a milestone apart:
 The first form is a **bounded blocking channel** (`system/kernel/ipc.zig`): a fixed-size
 ring buffer of messages with a producer/consumer rendezvous, built on the
-scheduler's [wait queues](../os-development-guide/scheduling.md).
+scheduler's [wait queues](../os-development/scheduling.md).
 `Channel(T, capacity)` is generic over the message type and buffer size. It holds a
 ring buffer, a count, and two wait queues:
@@ -37,7 +37,7 @@ Two details make it correct:
  rather than assuming the slot is still available — another waiter may have taken
  it first. This is the standard guard against spurious or racing wakeups.
 - **One critical section.** `send`/`receive` run under the [big kernel
-  lock](../os-development-guide/smp.md) (`sync.enter` / `sync.leave`), which disables interrupts on this
+  lock](../os-development/smp.md) (`sync.enter` / `sync.leave`), which disables interrupts on this
  core *and* takes the kernel's one spinlock — since SMP, the interrupt flag alone
  is not atomicity, because `cli` on one core does nothing to another. So checking
  the condition and committing the block/enqueue happen atomically both with respect
@@ -114,7 +114,7 @@ This is what makes a user-space driver possible at all, and it's the subject of
 ## Lifecycle conventions over IPC (M17)
-Three conventions from [process-lifecycle.md](../os-development-guide/process-lifecycle.md) ride the
+Three conventions from [process-lifecycle.md](../os-development/process-lifecycle.md) ride the
 notification mechanism:
 - **Signals** arrive as notifications on the endpoint a process nominated with
@@ -49,7 +49,7 @@ addressed by device id. `/dev` is the much smaller set of devices that have a dr
 willing to serve them, addressed by name.
 A device node is not a file the VFS can read. The bytes live in a driver process
-([drivers.md](../device-driver-development-guide/drivers.md)), so opening a `/dev` name has to resolve to that driver's
+([drivers.md](../device-driver-development/drivers.md)), so opening a `/dev` name has to resolve to that driver's
 IPC endpoint, and subsequent reads and writes are calls against it. Resolve-to-endpoint
 is exactly what the kernel's `fs_resolve` already does for any mounted backend, and
 `FileStatus.kind` is the field that marks a device node; **what is not implemented today
@@ -92,7 +92,7 @@ descriptor ring and left to read and write memory on its own. That ring is exact
 **`dma_alloc`** now provides — physically contiguous, pinned, uncacheable, with its
 physical address disclosed — and **`/lib/device/mmio`**'s barriers order the descriptor writes
 against the doorbell, and **`msi_bind`** delivers completions. So an AHCI or NVMe driver
-can be written today (the M14/M15 work in [driver-model.md](../device-driver-development-guide/driver-model.md); the earlier
+can be written today (the M14/M15 work in [driver-model.md](../device-driver-development/driver-model.md); the earlier
 "cannot host a block driver at all" is no longer true).
 What is *not* yet true is that it is safe. A device programmed with an arbitrary physical
@@ -9,7 +9,7 @@
 > backend, unchanged. The Zig source of truth is `library/protocol/vfs/vfs-protocol.zig`
 > (the `vfs-protocol` module), whose unit test pins a sample of the sizes
 > and values below. This page is the **language-neutral wire specification**
-> of that contract — what a Rust or C client implements ([vdso.md](../os-development-guide/vdso.md)
+> of that contract — what a Rust or C client implements ([vdso.md](../os-development/vdso.md)
 > explains why the IPC protocols, not the syscall numbers, are danos's
 > public ABI).
@@ -1,9 +0,0 @@
 # OS Developer Guide
 This document is for those who need to understand the architectural decisions behind the OS.
 ## Written in Zig?
 The os was initially written in zig because it has excellent support for EFI. With zig, we could forgo using a third party bootloader, reducing the time to boot up the kernel. Following the "Zen of Zig", helped to produce the most readable codebase for an operating system ever created. So those, new to OS development could quickly get up to speed.
@@ -0,0 +1,39 @@
 # OS Development
 This document explains the architectural decisions behind the operating system.
 ## Written in Zig?
 The OS is written in Zig because it has excellent EFI support, so the OS boots quickly without a third-party bootloader.
 Zig comes batteries included for systems work — cross-compilation, a build system, and a test runner are all part of the toolchain. Building with `-Doptimize=ReleaseSafe` keeps runtime safety checks on in the shipped kernel, which removes entire classes of bugs. The built-in test suite, combined with a QEMU integration harness, means every feature is proven to work, before it is shipped.
 The codebase of the OS prioritizes readability. The aim is a codebase where someone new to OS development can find their way around without a guide.
 ## A microkernel?
 The kernel is a thin layer: it schedules processes and manages memory. Everything else — drivers, file systems, the display — runs in user space as separate, isolated processes.
 The payoff is resilience. When a driver crashes, it doesn't take the OS down with it; it gets restarted. That makes this an ideal environment for *developing* an operating system, because a buggy driver is an ordinary bug: patch it, restart the service, and keep going.
 There is a security benefit too. Processes are isolated and talk over Inter-Process Communication (IPC) channels, so compromising one service doesn't hand an attacker the whole machine. Vulnerabilities tend to stay contained in the process they started in.
 Other operating systems choose to pack all of these duties into one binary as a Monolithic kernel, mostly for performance: a function call inside the kernel is faster than passing a message between isolated processes. That cost is real — an IPC round-trip is a few microseconds where a function call is nanoseconds — but it is also workload-shaped. Compute-bound programs don't notice it at all. For bulk data like file contents and pixels, the design moves data through shared memory and DMA so it is copied once, the same as a monolithic kernel; only small control messages cross the IPC boundary. What remains is the per-message cost on chatty paths, and the scheduler and memory management are designed to keep that small.
 ## Private ABI
 The syscall layer is private. The numbers and structures in `abi.zig` are an internal detail shared between the kernel and the system's own libraries, and they are free to change between builds.
 The public boundary sits one level up: the [vDSO](vdso.md) that programs call into, and the documented IPC protocols such as the [VFS protocol](../file-system-development/vfs-protocol.md). Programs that stick to those interfaces keep working while the kernel rearranges itself underneath. This is the opposite of the Linux approach, where raw syscall numbers are frozen forever; here, stability is promised at the library and protocol level, and nowhere below it.
 ## Steal the best bits and dump the legacy
 The OS is Unix-like, but selectively. It borrows the ideas that have aged well — everything is a file, small services composed over clean interfaces — and skips the parts of POSIX that have caused decades of headaches.
 Some concrete choices:
 - **`spawn`, not `fork`.** Creating a process starts a fresh program and returns the child's id. There is no clone-the-whole-address-space-then-immediately-throw-it-away dance, and none of the subtle state-inheritance bugs that come with it.
 - **Time is a syscall.** The kernel owns the clock and timers directly. There is no time daemon to keep alive and no ambiguity about where the truth lives.
 - **Lifecycle events arrive as messages.** A supervisor learns that a child exited through an IPC message on an endpoint it already owns — delivered like any other message, not as an interrupt that can fire between any two instructions.
 The test for keeping an idea is simple: does it still pull its weight, or is it only there because it was there in 1979?
@@ -75,7 +75,7 @@ There are really two independent questions, and it's worth not conflating them:
 - **`system/kernel/architecture/x86_64/paging.zig`** — the kernel's page tables and address-space
  management (see [paging.md](paging.md)).
 - **`system/kernel/architecture/x86_64/apic.zig`** / **`ioapic.zig`** — the Local APIC, its timer,
-  and the I/O APIC for device interrupts (see [device-interrupts.md](../device-driver-development-guide/device-interrupts.md)).
+  and the I/O APIC for device interrupts (see [device-interrupts.md](../device-driver-development/device-interrupts.md)).
 - **`system/kernel/architecture/x86_64/serial.zig`** / **`io.zig`** — the COM1 UART (the kernel's
  machine-readable log channel, see [testing.md](../testing.md)) and the shared port-I/O + MSR primitives.
 - **`system/kernel/architecture/x86_64/smp.zig`** / **`per-cpu.zig`** — application-processor bring-up
@@ -132,7 +132,7 @@ when*:
 - **User-space enumeration: a device-manager server.** Everything else — PCI devices,
  peripherals — is parsed (or queried from the kernel's parse) by a privileged
  user-space server that hands each driver process its MMIO regions and IRQ rights
-  over [IPC](../device-driver-development-guide/ipc.md). Combined with **interrupts-as-messages** (an IRQ delivered to a
+  over [IPC](../device-driver-development/ipc.md). Combined with **interrupts-as-messages** (an IRQ delivered to a
  driver as a message on a channel — a natural extension of the wait queues and
  channels already built), that's what makes drivers genuinely isolated.
@@ -144,7 +144,7 @@ slice is unavoidably in-kernel.
 On ARMv8 the generic timer exposes its frequency directly via the `CNTFRQ` register —
 no calibration needed. That's cleaner than the x86 side, where we measure the LAPIC
 and TSC against the PIT because nothing tells us their frequency (see
-[device-interrupts.md](../device-driver-development-guide/device-interrupts.md)). Discovery on ARM hands you more for
+[device-interrupts.md](../device-driver-development/device-interrupts.md)). Discovery on ARM hands you more for
 free; discovery on x86 is partly about *finding* what ARM just tells you.
 ## Suggested ordering
@@ -166,9 +166,9 @@ free; discovery on x86 is partly about *finding* what ARM just tells you.
 - [arm.md](arm.md) — the aarch64 target that forces genuine discovery (DTB, GIC).
 - [memory-map.md](memory-map.md) — the same loader-captures / kernel-consumes seam,
  and the note about grabbing the RSDP before `ExitBootServices`.
- [device-interrupts.md](../device-driver-development-guide/device-interrupts.md) — the LAPIC/timer bring-up that
+- [device-interrupts.md](../device-driver-development/device-interrupts.md) — the LAPIC/timer bring-up that
  discovery will eventually feed (IOAPIC, real IRQ routing).
- [ipc.md](../device-driver-development-guide/ipc.md) — the channels that interrupts-as-messages and the device manager
+- [ipc.md](../device-driver-development/ipc.md) — the channels that interrupts-as-messages and the device manager
  will ride on.
 - [vision.md](../vision.md) — why drivers belong in isolated user space at all.
@@ -177,7 +177,7 @@ free; discovery on x86 is partly about *finding* what ARM just tells you.
 The kernel now seeds only the `pci_host_bridge` node (ECAM window, MMIO
 apertures derived from the memory map's holes, bus range, and the 16-bit I/O
 window). The per-function walk moved to the ring-3 `pci-bus` driver
-([device-manager.md](../device-driver-development-guide/device-manager.md)): it claims the bridge, repeats the
+([device-manager.md](../device-driver-development/device-manager.md)): it claims the bridge, repeats the
 ECAM scan through its mmio grant, and `device_register`s what it finds, which
 the device manager mirrors and matches. The ACPI namespace walk follows in M20;
 the static tables (MADT, HPET, MCFG, FADT + `\\_S5`) stay kernel-side.
@@ -190,7 +190,7 @@ for the host bridge, FADT); at this point it also still built the AML namespace
 but only to read the `\\_S5` sleep type for poweroff. (That remnant is gone too:
 the kernel now runs no AML at all — soft-off belongs to the acpi service, and the
 kernel keeps only the AML-free reboot path.) Device discovery is the ring-3 **acpi
-service** ([device-manager.md](../device-driver-development-guide/device-manager.md)): it claims the `acpi-tables`
+service** ([device-manager.md](../device-driver-development/device-manager.md)): it claims the `acpi-tables`
 node the kernel publishes (the AML blobs, a broad io_port grant, the SCI),
 re-parses the same blobs with the shared AML module, evaluates `_STA`/`_CRS`,
 and registers + reports each `_HID` device — the device manager matches drivers
@@ -206,7 +206,7 @@ ring 0.)
 Moving PCI and ACPI enumeration out of ring 0 was not just a relocation — it
 made discovery **firmware-neutral by construction**, which is the whole reason
 to do it before the second architecture rather than after. Everything at and
-above the [device-manager](../device-driver-development-guide/device-manager.md) protocol — descriptors,
+above the [device-manager](../device-driver-development/device-manager.md) protocol — descriptors,
 containment, reports, matching, supervision — is generic and may never become
 x86-specific. Discovery is the single firmware-specific piece, and it is
 isolated as **one swappable process per firmware**:
@@ -136,7 +136,7 @@ Both items originally deferred here have landed:
 - **The IO-APIC**: [ioapic.zig](../../system/kernel/architecture/x86_64/ioapic.zig)
  routes external device lines onto vectors — discovered via ACPI's MADT, every
  input masked at init, lines unmasked one at a time as user-space drivers bind
-  them (see [device-interrupts.md](../device-driver-development-guide/device-interrupts.md)). The keyboard followed
+  them (see [device-interrupts.md](../device-driver-development/device-interrupts.md)). The keyboard followed
  exactly as predicted: the PS/2 bus driver (`system/drivers/ps2-bus/`) claims
  the 8042 controller and binds its IRQ 1 (and the aux mouse's IRQ 12) through
  this routing. USB HID keyboards arrive over xHCI instead, which interrupts via
@@ -138,8 +138,8 @@ Four tests (see [testing.md](../testing.md)) pin down the guarantees:
  processes own the low half.
 - **Per-address-space tables** — done: each user process gets its own root with
  the kernel half shared, and refcounted shared-memory mappings exist
-  ([ipc.md](../device-driver-development-guide/ipc.md)). Copy-on-write remains unbuilt — nothing has needed it yet.
+  ([ipc.md](../device-driver-development/ipc.md)). Copy-on-write remains unbuilt — nothing has needed it yet.
 - **Uncacheable MMIO** — half done: user-space device and DMA mappings are
  strong-uncacheable and the framebuffer is write-combining via the PAT, but the
  kernel's own `mapMmio` path is still writeback — the LAPIC included (see
-  [device-interrupts.md](../device-driver-development-guide/device-interrupts.md)).
+  [device-interrupts.md](../device-driver-development/device-interrupts.md)).
@@ -7,7 +7,7 @@ them owns the hardware that reported the event, and the reporter should not know
 who is listening. So system power is a **service**: an event source **publishes**
 button/lid/battery/AC events, interested processes **subscribe**, and one
 privileged caller — init — can ask it to power the machine off. It is the same
-publish/subscribe shape as the [input service](../device-driver-development-guide/input.md), applied to power.
+publish/subscribe shape as the [input service](../device-driver-development/input.md), applied to power.
 ## Why a service, and why it is named for the domain, not the firmware
@@ -126,5 +126,5 @@ until laptop sleep), and thermal zones.
  firmware neutrality that makes a PSCI backend drop-in on ARM.
 - [process-lifecycle.md](process-lifecycle.md) — the stop sequence
  (`terminate → deadline → kill`) and signals init composes into shutdown.
- [device-manager.md](../device-driver-development-guide/device-manager.md) — the supervision model init mirrors for
+- [device-manager.md](../device-driver-development/device-manager.md) — the supervision model init mirrors for
  its own children.
@@ -9,7 +9,7 @@ the layer above them — the standard vocabulary a danos process speaks about it
 life, and the stable `process` interface that carries it. Nothing here is
 device- or driver-specific: a driver, the VFS, and a user application all stop,
 reload, and die the same way. The device manager is simply this design's first
-serious customer ([device-manager.md](../device-driver-development-guide/device-manager.md)).
+serious customer ([device-manager.md](../device-driver-development/device-manager.md)).
 **"POSIX" in this document means the concepts, never the letter of the standard.**
 danos borrows the ideas and the hard-won lessons (what SIGTERM *means*, why SIGPIPE
@@ -172,7 +172,7 @@ zombie state or privileged snooping:
   the server's reply with `-EPEER`; a server that dies fails its waiting clients
   the same way. This covers the *synchronous* case only.
 3. **The subscribers** — the new piece, and it is the input service's
-   publish/subscribe shape ([input.md](../device-driver-development-guide/input.md)) applied to exits. A stateful
+   publish/subscribe shape ([input.md](../device-driver-development/input.md)) applied to exits. A stateful
   service accumulates per-client state across many requests: a filesystem server
   (FAT today) holds a dead client's open file handles, the input service holds
   its subscriptions, a future network stack holds its sockets. None of these
@@ -320,7 +320,7 @@ get POSIX; danos-native programs never pay for it.
   `process` grows the interface above; the service harness handles
   `terminate` and answers the common `ping`; `stop()` for supervisors.
-[device-manager.md](../device-driver-development-guide/device-manager.md) builds directly on all four.
+[device-manager.md](../device-driver-development/device-manager.md) builds directly on all four.
 ## Settled questions (2026-07-12)
@@ -5,7 +5,7 @@ isolation; fault → kill the process → keep the core (`onException`; the
 `fault-recovery` test); the supervisor notification **with exit reasons**
 ([process-lifecycle.md](process-lifecycle.md) — clean exit, fault class, or
 killed, recorded before the notice posts); and the **restart policy itself**
-([device-manager.md](../device-driver-development-guide/device-manager.md)): the device manager supervises every
+([device-manager.md](../device-driver-development/device-manager.md)): the device manager supervises every
 driver, restarts crashes with backoff, caps crash loops, and re-claims work
 because the kernel releases a dead process's claims. The `driver-restart` and
 `usb-report` scenarios prove kill → release → respawn → re-claim → re-report
@@ -81,7 +81,7 @@ Detecting and killing is the easy half. The genuinely tricky questions are about
 - **In-flight IPC**: messages sent to the dead component, or replies its clients are
  blocked waiting for. The channel has to break cleanly and unblock the waiters with
  an error rather than hang them forever (a design constraint that reaches back into
-  [ipc.md](../device-driver-development-guide/ipc.md) — channels need a "peer died" outcome).
+  [ipc.md](../device-driver-development/ipc.md) — channels need a "peer died" outcome).
 - **Clients**: how does a client discover the service it was talking to is gone and
  has been replaced? Options: capability revocation makes stale handles fail; or a
  **name server** re-binds clients to the new instance; or clients retry through a
@@ -159,7 +159,7 @@ real-time work without owing anyone a timing *guarantee*.
 - [vision.md](../vision.md) — the goals this serves (learning by doing; resilience over
  hard real-time).
 - [scheduling.md](scheduling.md) — preemption, which makes runaway components killable.
- [ipc.md](../device-driver-development-guide/ipc.md) — channels that need a "peer died" outcome for clean restart.
+- [ipc.md](../device-driver-development/ipc.md) — channels that need a "peer died" outcome for clean restart.
 - [interrupts.md](interrupts.md) — fault reporting that user mode turns into "kill and
  restart" instead of "halt".
 - [smp.md](smp.md) — the real-time-vs-resilience fork, in the SMP context.
@@ -37,7 +37,7 @@ down a return address pointing at `task_trampoline` and zeroed callee-saved slot
 `schedule()` — pick the best task and switch — runs from two places:
 - **`yield()`** — a task voluntarily gives up the CPU.
- **`tick()`** — the 1000 Hz [timer](../device-driver-development-guide/device-interrupts.md) preempts the running
+- **`tick()`** — the 1000 Hz [timer](../device-driver-development/device-interrupts.md) preempts the running
  task. This is what lets a task that never yields still share the CPU.
 The subtlety in mixing them is the **interrupt flag (IF)**. The rule: `switch_context`
@@ -97,7 +97,7 @@ marks the task blocked with a wake deadline and switches away. On every tick the
 timer wakes any task whose deadline has passed (a bounded scan, so it stays
 deterministic), which makes it ready again; the scheduler then runs it when its
 priority comes up. `sleep` measures its deadline on the [calibrated
-clock](../device-driver-development-guide/device-interrupts.md), so it's real time.
+clock](../device-driver-development/device-interrupts.md), so it's real time.
 When *every* task is blocked, something still has to run — so there's an **idle
 task** at the lowest priority that just `hlt`s until the next interrupt (see
@@ -111,7 +111,7 @@ The other form of blocking is waiting for an **event** rather than a duration. A
 the caller on it, `wake(wq)` moves the highest-priority waiter back to ready
 (preempting if it now outranks the running task). A task links into a wait queue
 through the same field the ready queues use — it's in exactly one queue at a time.
-These are the primitives locks, semaphores and [IPC](../device-driver-development-guide/ipc.md) are built on.
+These are the primitives locks, semaphores and [IPC](../device-driver-development/ipc.md) are built on.
 Blocking safely needs **composable critical sections**. A blanket `cli`/`sti` pair
 doesn't nest: an IPC channel that `cli`s and then calls `wait` would have `wait`'s
@@ -307,4 +307,4 @@ refcount, and no group-kill special case is needed at all.
  Then update [threading.md](threading.md) (the shared-fate gap note),
  [process-lifecycle.md](process-lifecycle.md),
  [process-management.md](process-management.md), and
-  [ipc.md](../device-driver-development-guide/ipc.md)/[drivers.md](../device-driver-development-guide/drivers.md) mentions.
+  [ipc.md](../device-driver-development/ipc.md)/[drivers.md](../device-driver-development/drivers.md) mentions.
@@ -270,6 +270,6 @@ next lands.
 - [scheduling.md](scheduling.md) — the single-core scheduler SMP would extend.
 - [discovery.md](discovery.md) — enumerating cores is a device-discovery problem.
- [ipc.md](../device-driver-development-guide/ipc.md) — the message passing cross-core coordination rides on.
+- [ipc.md](../device-driver-development/ipc.md) — the message passing cross-core coordination rides on.
 - [vision.md](../vision.md) — the goals question (real-time vs resilience) this note
  keeps bumping into.
@@ -51,7 +51,7 @@ Everything else---including`read()`,`write()`,`malloc()`, and`fork()`---will run
 3.  **`Yield()`/`Thread_Ctrl()`**
    -   **What it does:**Allows a thread to voluntarily give up its CPU time slice, or allows a root task to spawn/kill threads.
 4.  **`ipc_send(endpoint, message_buffer)`(Asynchronous Send)**
-    -   **What it does:**Posts a small payload to an endpoint's bounded queue and returns *without* blocking — no rendezvous, no reply. The receiver picks it up through the same `IPC_ReplyWait`, as a buffered message. It is the async counterpart of `IPC_Call`, for one-to-many broadcasts where a synchronous rendezvous would let one dead or slow receiver hang the sender. The [input service](../device-driver-development-guide/input.md) — keyboard-event fan-out — is its first user. A full queue drops the oldest message (a buffered message is discrete data, unlike a coalescing interrupt notification).
+    -   **What it does:**Posts a small payload to an endpoint's bounded queue and returns *without* blocking — no rendezvous, no reply. The receiver picks it up through the same `IPC_ReplyWait`, as a buffered message. It is the async counterpart of `IPC_Call`, for one-to-many broadcasts where a synchronous rendezvous would let one dead or slow receiver hang the sender. The [input service](../device-driver-development/input.md) — keyboard-event fan-out — is its first user. A full queue drops the oldest message (a buffered message is discrete data, unlike a coalescing interrupt notification).
 * * * * *
@@ -2,7 +2,7 @@
 The ordered, checkpointable build-out for [threading.md](threading.md). Each milestone
 lands on its own and ends in a **verifiable gate** — shaped for a `/loop` run, like
-[display-v2-plan.md](../device-driver-development-guide/display-v2-plan.md). Read threading.md first for the *why*.
+[display-v2-plan.md](../device-driver-development/display-v2-plan.md). Read threading.md first for the *why*.
 ## Locked decisions (do not relitigate)
@@ -459,7 +459,7 @@ clean.
 ## Deferred (explicitly not in this plan)
 - **Cross-process shared-memory futex** — the `(address_space, virtual_address)` key can become a
-  physical-address key so two processes share a futex through a [shared-memory](../device-driver-development-guide/display-v2.md)
+  physical-address key so two processes share a futex through a [shared-memory](../device-driver-development/display-v2.md)
  region. Not needed for intra-process threads.
 - **Per-thread priorities / affinity distinct from the process** — threads inherit the
  process priority ([scheduling.md](scheduling.md)); revisit only if it earns its keep.
@@ -36,7 +36,7 @@ implementation underneath, not the API above.
  [Why not literal std.Thread](#why-not-literal-stdthread).
 - **Threads are a narrow, opt-in capability — not the default concurrency tool.** The
  default for resilience stays **process + IPC** ([resilience.md](resilience.md),
-  [ipc.md](../device-driver-development-guide/ipc.md)). See [Where threads fit](#where-threads-fit-the-resilience-tension).
+  [ipc.md](../device-driver-development/ipc.md)). See [Where threads fit](#where-threads-fit-the-resilience-tension).
 - **Blocking synchronization is futex-backed, never spin-backed.** Waiters sleep in
  the kernel so an idle core still halts ([halting.md](halting.md)).
 - **Per-binary opt-in to multi-threaded codegen.** Only a service that asks for
@@ -214,7 +214,7 @@ Keying: threads share an address space, so a **virtual address within that addre
 identifies a futex uniquely; the kernel keys its wait queue by `(address_space_root, virtual_address)`.
 Keying by the **physical** address instead (translate `virtual_address -> physical_address` on entry) is a
 deliberate forward door: it lets two *processes* share a futex through an
-[shared-memory](../device-driver-development-guide/display-v2.md) region later, without changing the API. We start with the
+[shared-memory](../device-driver-development/display-v2.md) region later, without changing the API. We start with the
 private-per-address-space key and note the physical-key upgrade.
 No spinning: a contended lock parks the task in the kernel and the core is free to run
@@ -264,7 +264,7 @@ stays single-threaded and lean.
  **process**, which respawns its threads from a known-good state — restart
  granularity stays the process. The leader's recorded exit reason carries the fault
  class even when a worker faulted, so restart policy is unchanged.
- **IPC — two consequences threads forced ([ipc.md](../device-driver-development-guide/ipc.md)):**
+- **IPC — two consequences threads forced ([ipc.md](../device-driver-development/ipc.md)):**
  - *Handles do not cross threads.* The handle table lives on the `Task`
    ([scheduler.zig](../../system/kernel/scheduler.zig)), so a handle number is meaningful
    only to the thread that created it — thread A's endpoint handle `3` is not thread B's.
@@ -284,7 +284,7 @@ stays single-threaded and lean.
 The ordered, `/loop`-runnable milestones live in
 **[threading-plan.md](threading-plan.md)** (shaped like
-[display-v2-plan.md](../device-driver-development-guide/display-v2-plan.md)): every milestone lands on its own and ends in
+[display-v2-plan.md](../device-driver-development/display-v2-plan.md)): every milestone lands on its own and ends in
 a verifiable gate (`python3 test/qemu_test.py <case>`, asserting serial markers;
 `zig build test` for host unit tests). The stages below are the shape it expands.
@@ -343,7 +343,7 @@ the later self-hosting lift cheap.
 - [scheduling.md](scheduling.md), [smp.md](smp.md) — the task model these threads join.
 - [resilience.md](resilience.md), [vision.md](../vision.md) — why isolation is the default
  and threads are the exception.
- [syscall.md](syscall.md), [ipc.md](../device-driver-development-guide/ipc.md) — the private ABI and the messaging model
+- [syscall.md](syscall.md), [ipc.md](../device-driver-development/ipc.md) — the private ABI and the messaging model
  threads sit beside.
 - [halting.md](halting.md) — the idle/halt property futex-backed blocking preserves.
 - [zig-self-hosting.md](../zig-self-hosting.md) — the target this bends toward.
@@ -7,7 +7,7 @@ Two different needs hide under the word "timer", and danos keeps them apart:
 Both are answered by the **kernel**, because the kernel already owns a timer: it has
 to, to preempt tasks. The LAPIC heartbeat and the calibrated TSC that back all of this
-are built in [device-interrupts.md](../device-driver-development-guide/device-interrupts.md); the scheduler's blocking and
+are built in [device-interrupts.md](../device-driver-development/device-interrupts.md); the scheduler's blocking and
 wait queues are in [scheduling.md](scheduling.md). This page is about the surface a
 ring-3 program actually uses, and one deliberate absence: **there is no user-space time
 service.**
@@ -32,11 +32,11 @@ danos checks both — the invariant-TSC CPUID bit (`0x80000007` EDX[8], set on I
 AMD), and a cross-core "warp" check as the cores come up — and falls back to the HPET
 counter when either fails. So `now()` stays accurate on a real Intel box, a real AMD box,
 and inside a VM alike; only the source behind it differs. The mechanism is in
-[device-interrupts.md](../device-driver-development-guide/device-interrupts.md).
+[device-interrupts.md](../device-driver-development/device-interrupts.md).
 So the timer hardware lives in the kernel, and there is **no `hpet` driver and no time
 server** to consume. (An earlier HPET driver existed only to *demonstrate* the driver
-model; that role now lives in [drivers.md](../device-driver-development-guide/drivers.md), as documentation.) The one place
+model; that role now lives in [drivers.md](../device-driver-development/drivers.md), as documentation.) The one place
 a user-space time service *is* justified — **wall-clock / calendar time** — is discussed
 at the end; it is deliberately not built yet.
@@ -55,7 +55,7 @@ Time and waiting are three entries in the small syscall table ([syscall.md](sysc
  service can keep answering messages on the same endpoint while a deadline is pending.
  This is the timed wait that stop-sequence escalation, hello deadlines, and restart
  backoff are built from ([process-lifecycle.md](process-lifecycle.md),
-  [device-manager.md](../device-driver-development-guide/device-manager.md)).
+  [device-manager.md](../device-driver-development/device-manager.md)).
 The kernel's own scheduling timer (the LAPIC, vector 32) is never exposed to user space;
 programs read the TSC through `clock` and get timed wakeups through `sleep`/`timer_bind`,
@@ -118,7 +118,7 @@ hypervisor configured for UEFI firmware and an xHCI USB controller.
  (`system/kernel/acpi.zig:3`)
 - The loader reads `/system/kernel` off the FAT boot volume, then loads user
  space: a prebuilt `boot\system.img` capsule
-  ([system-image.md](os-development-guide/system-image.md)) when present, otherwise it walks
+  ([system-image.md](os-development/system-image.md)) when present, otherwise it walks
  the volume's `/system` and optional `/test` trees (init included) into the
  initial ramdisk. The kernel can boot "kernel-only" without either.
  (`efi.zig:16`, `efi.zig:68`)
@@ -27,7 +27,7 @@ boot log, memory summary, exception reports — appears on serial as plain text.
 QEMU captures that with `-serial file:serial.log`, giving a machine-readable
 transcript. Serial is per-architecture (x86 uses port I/O; an ARM board uses a
-memory-mapped UART), so it lives behind the [architecture](os-development-guide/architecture.md) boundary — and adding
+memory-mapped UART), so it lives behind the [architecture](os-development/architecture.md) boundary — and adding
 a new architecture's UART is what makes the same tests run there.
 The serial log sink is **compiled in only under `-Dserial`** (off by default).
@@ -88,7 +88,7 @@ table in `test/qemu_test.py`):
 | `fault-recovery` | a ring-3 process that faults is killed and reaped while init keeps heartbeating — the OS survives | `DANOS-TEST-RESULT: PASS` |
 The faulting cases don't print a result line — they deliberately raise a CPU
-exception, and the harness asserts on the [exception report](os-development-guide/interrupts.md) the
+exception, and the harness asserts on the [exception report](os-development/interrupts.md) the
 handler prints (which also reaches serial). This reuses the real fault path as the
 test oracle: if the IDT/TSS weren't wired up, `fault-df` would triple-fault and the
 marker would never appear.
@@ -108,7 +108,7 @@ localised (below).
 ## The architecture decision: `runtime.os` + `runtime.fs`, and retire `posix`
 danos already has the right split ([the private-ABI boundary](../README.md)): the
-kernel exposes a minimal syscall ABI ([syscall.md](os-development-guide/syscall.md)); the **`runtime`**
+kernel exposes a minimal syscall ABI ([syscall.md](os-development/syscall.md)); the **`runtime`**
 library is the stable, danos-native application ABI. What this roadmap adds:
 - **`runtime.os` — the seam.** A C-ABI-shaped module of the ~30 operations
@@ -165,7 +165,7 @@ What the seam needs, and what danos already provides:
 | mmap / munmap | native syscalls ([abi.zig](../system/abi.zig)) | none |
 | page allocator | over `mmap`, via `root.os.heap.page_allocator` override | ~30-line hook |
 | monotonic clock | `clock` syscall | none |
-| args / argv | SysV entry stack ([sysv.md](os-development-guide/sysv.md)), `runtime.process.Init` | none |
+| args / argv | SysV entry stack ([sysv.md](os-development/sysv.md)), `runtime.process.Init` | none |
 | stdout / stderr | `debug_write` today | wire fd 1/2 to a console **byte** stream |
 | mkdir / unlink / rename / truncate | done — engine + VFS + `runtime.fs` (Phase 2) | — |
 | stat fields | `{size, kind, mtime}` | **mode / inode** still missing (cache validity) |
@@ -209,7 +209,7 @@ build); point danos's `build.zig`/CI at the resulting binary. Four localised pat
  plan9/serenity;
 - add `danos` to the freestanding/other **no-op `_start` list** in `std`'s `start.zig`,
  so std does *not* emit its own System-V `_start` — danos keeps owning the entry shim
-  and `Init`/argv construction it already builds ([sysv.md](os-development-guide/sysv.md));
+  and `Init`/argv construction it already builds ([sysv.md](os-development/sysv.md));
 - wire the `system` selector `.danos => std.os.danos` in `std.posix`;
 - add `std/os/danos.zig` — **the seam itself**, promoted near-verbatim from the
  `runtime.os` developed first in Phase 1 (against the stock toolchain, so the fork is
@@ -344,9 +344,9 @@ Two current decisions fall out of this roadmap:
 ## Related
 - [vision.md](vision.md) — the north star this serves.
- [syscall.md](os-development-guide/syscall.md) — the kernel↔runtime ABI `runtime.os` is built on.
+- [syscall.md](os-development/syscall.md) — the kernel↔runtime ABI `runtime.os` is built on.
- [sysv.md](os-development-guide/sysv.md) — the entry stack (`argc/argv/envp/auxv`) danos already constructs.
+- [sysv.md](os-development/sysv.md) — the entry stack (`argc/argv/envp/auxv`) danos already constructs.
- [ipc.md](device-driver-development-guide/ipc.md) — the IPC the VFS/FAT operations travel over.
+- [ipc.md](device-driver-development/ipc.md) — the IPC the VFS/FAT operations travel over.
 - [danos-file-system-hierarchy-FSH.md](file-system-development/danos-file-system-hierarchy-FSH.md) — the
  filesystem layout the file surface serves.
 - [coding-standards.md](coding-standards.md) — danos naming (why the compat spellings
@@ -1,6 +1,6 @@
 # xkeyboard-config — X11 keyboard layouts, compiled to Zig
-This module turns a physical key (a **USB HID usage**, as the [input module](../../docs/device-driver-development-guide/input.md)
+This module turns a physical key (a **USB HID usage**, as the [input module](../../docs/device-driver-development/input.md)
 delivers in `KeyEvent.keycode`) plus a modifier state into a **keysym** and, when the key
 produces one, a **character** (a Unicode scalar). It is what lets a `keycode` become a
 `character` — a keymap — without danos shipping an X11 runtime.