feat(build): borealis-style multi-stage rootfs for the open guest components (#309)

## What

Adds `build/` — a Dockerfile with `mesa-build`, `nestri-build`,
`os-base`, `runtime`, `runtime_prod` and `runtime_debug` stages, plus
the `etc/` overlay, `mkimage.sh` and a `Makefile` — laid out the way
[borealis](https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/main/project-borealis)
lays out its own `build/`. This moves the guest rootfs formula into this
repo, targeting the four open guest components already here: `nescope`,
`neshub`, `neswire`, `nescapture`.

## Two structural properties worth calling out

- **No privileged host chroot.** A bare `chroot` into a hand-extracted
rootfs needs `/proc`, `/sys`, `/dev` bind-mounted in first. `os-base`
here is `FROM artixlinux/artixlinux:base-openrc` directly with `pacman
-S` as plain `RUN` steps — a Docker build step already has its own
`/proc`/`/sys`/`/dev`.
- **No host-side ownership bug to guard against.** `COPY --from=` runs
as root inside the build with no invoking-user uid in the loop.

## Scope boundary

**Deliberately excludes Proton and Valve's `steamclient.so`** — both
closed, and `CLAUDE.md` forbids closed content in this repo.
`runtime_prod`, tagged `nestrilabs/nestri:base`, is a complete,
bootable, Steam-less image — and also the shared foundation other builds
start from. Whatever layers Proton/Steam on top of it is a closed build
outside this repo, by design.

## Known gap

Nothing starts a payload yet — `nesinit` isn't open code — so
`/etc/init.d/nescope` boots it in plain-compositor mode (no command
after `--`) rather than running a game. Real and testable, just not a
full session yet. Details in `build/README.md`.

## Status

Built and tagged locally as `nestrilabs/nestri:base` (podman, no
`--no-cache` issues, greptile's three findings all fixed and verified
against a real build). Not yet packed into a disk image or run inside
nesbox.

🤖 Generated with [Claude Code](https://claude.com/claude-code)






<!-- greptile_comment -->

<h3>Greptile Summary</h3>

The PR adds a multi-stage Artix/OpenRC guest-rootfs build for the open
Nestri components, with production and debug image flavors.
- Builds patched Mesa and the Rust workspace in dedicated builder
stages.
- Assembles and configures the bootable guest environment and OpenRC
services.
- Packs a selected container image into an ext4 root filesystem while
retaining rootless container storage access.

<h3>Confidence Score: 5/5</h3>

The PR appears safe to merge.

No blocking failure remains.

<h3>Important Files Changed</h3>




| Filename | Overview |
|----------|----------|
| build/Dockerfile | Defines the complete multi-stage build, overlays
repository-root-relative configuration paths, and creates production and
debug runtime targets. |
| build/Makefile | Provides consistent image build and packing targets
using a repository-root context and matching image tags. |
| build/scripts/mkimage.sh | Keeps container-runtime operations in the
invoking user's storage while escalating only filesystem creation and
mounting operations. |
| build/etc/conf.d/nestri-user-env | Supplies the shared service
environment and export function required by the OpenRC service scripts.
|
| build/etc/init.d/guest-net | Configures optional guest networking from
kernel parameters or stable defaults. |
| build/etc/init.d/neswire | Starts the audio sink after its
dependencies and pins it as the PipeWire default once the graph is
ready. |


<h3>Flowchart</h3>

```mermaid
%%{init: {'theme': 'neutral'}}%%
flowchart TD
  A[Arch builder] --> B[Mesa build]
  A --> C[Nestri workspace build]
  D[Artix OpenRC base] --> E[Common runtime]
  B --> E
  C --> E
  F[build/etc overlay] --> E
  E --> G[runtime_prod]
  E --> H[runtime_debug]
  G --> I[Container image]
  H --> J[Debug container image]
  I --> K[mkimage.sh]
  J --> K
  K --> L[ext4 rootfs]
```

<sub>Reviews (6): Last reviewed commit: ["refactor(build): rename the
published
im..."](6fecc8cc31)
| [Re-trigger
Greptile](https://app.greptile.com/api/retrigger?id=58981739)</sub>

<!-- /greptile_comment -->

build/Dockerfile

@@ -0,0 +1,295 @@
+# ═══════════════════════════════════════════════════════════
+#  nestri guest rootfs — the open half
+#
+#  Builds a bootable Artix/OpenRC image containing Mesa (virtio-gpu native
+#  context) and the four open guest components: nescope, neshub, neswire,
+#  nescapture. Two leaf targets, selected with `--target`:
+#
+#    runtime_prod    stripped, root locked          (default: `make build`)
+#    runtime_debug    debug tools, autologin root    (`make build-debug`)
+#
+#  What is deliberately NOT here: Proton, Valve's steamclient.so, or anything
+#  else closed. nestri/CLAUDE.md is explicit that nothing closed enters this
+#  repo. Whatever layers those on top of runtime_prod is a closed build
+#  outside this repo — see build/README.md.
+#
+#  Build from the repo root, not from build/:
+#    docker build -f build/Dockerfile --target runtime_prod -t nestri-guest .
+#  (`make build` in this directory does exactly that.)
+# ═══════════════════════════════════════════════════════════
+
+
+# ───────────────────────────────────────────────────────────
+#  initial / builder — Arch, not Artix
+#
+#  The guest is Artix, but Artix's repos are Arch-derived and the toolchain/
+#  glibc generation is the same, while the archlinux image is the
+#  better-maintained of the two for actually compiling things. Only build
+#  artifacts leave these stages.
+# ───────────────────────────────────────────────────────────
+FROM docker.io/archlinux:base-devel AS initial
+RUN pacman -Syu --noconfirm
+
+FROM initial AS builder
+RUN pacman -S --noconfirm --needed \
+        cmake meson ninja git pkgconf \
+        python python-mako python-yaml python-packaging python-ply \
+        bison flex \
+        libpciaccess libepoxy libglvnd \
+        libx11 libxext libxrandr libxshmfence libxfixes libxxf86vm libxcb \
+        xcb-util-keysyms xorgproto \
+        wayland wayland-protocols \
+        expat zlib zstd libxml2 lm_sensors \
+        llvm clang libclc spirv-tools spirv-llvm-translator glslang \
+        elfutils libva libdrm directx-headers \
+        rust rust-bindgen cbindgen \
+        curl openssl \
+        pixman libxkbcommon \
+        vulkan-headers vulkan-icd-loader \
+        pipewire shaderc opus \
+        libinput \
+    && pacman -Scc --noconfirm
+WORKDIR /build
+ENV ARTIFACTS=/artifacts
+
+
+# ───────────────────────────────────────────────────────────
+#  Mesa — the only piece still fetched from outside this tree
+# ───────────────────────────────────────────────────────────
+FROM builder AS mesa-build
+
+ARG MESA_GIT=https://gitlab.freedesktop.org/mesa/mesa.git
+ARG MESA_COMMIT=b78fc73dd898a7dfa87448a4b5ff4459a870e21a
+
+RUN git clone --depth=1 --revision="${MESA_COMMIT}" "${MESA_GIT}" /build/mesa-src && \
+    cd /build/mesa-src && \
+    meson setup builddir \
+        -Dprefix=/usr \
+        -Dbuildtype=release \
+        -Dplatforms=wayland,x11 \
+        -Dgallium-drivers=zink,radeonsi,iris \
+        -Dvulkan-drivers=amd,intel \
+        -Damdgpu-virtio=true \
+        -Dintel-virtio-experimental=true \
+        -Dvideo-codecs=all \
+        -Degl=enabled \
+        -Dglx=dri \
+        -Dgles1=enabled \
+        -Dgles2=enabled \
+        -Dgbm=enabled \
+        -Dgallium-va=enabled \
+        -Db_ndebug=true && \
+    ninja -C builddir && \
+    DESTDIR=/artifacts/mesa ninja -C builddir install && \
+    rm -rf /build/mesa-src && \
+    find /artifacts/mesa -type f -printf '/%P\n' > /artifacts/mesa/.manifest
+
+
+# ───────────────────────────────────────────────────────────
+#  nestri workspace — same repo now, so this is COPY, not a private clone
+#
+#  One `cargo build --release --workspace` rather than one stage per binary:
+#  that per-repo splitting existed because nescope/neswire/nescapture/the hub
+#  were four separate private repos and a stage boundary was the only way to
+#  stop bumping one from invalidating the others' build cache. They are one
+#  Cargo workspace with one Cargo.lock now, so a BuildKit cache mount on
+#  target/ gives the same isolation — cargo's own incremental compiler
+#  already knows nescope changing does not touch nesprotocol's .rlib — without
+#  four copies of every shared dependency getting compiled once per stage.
+# ───────────────────────────────────────────────────────────
+FROM builder AS nestri-src
+WORKDIR /build/nestri
+COPY Cargo.toml Cargo.lock ./
+COPY crates/nesprotocol crates/nesprotocol
+COPY apps/nescope apps/nescope
+COPY apps/neshub apps/neshub
+COPY apps/neswire apps/neswire
+COPY apps/nescapture apps/nescapture
+
+FROM nestri-src AS nestri-build
+RUN --mount=type=cache,target=/root/.cargo/registry \
+    --mount=type=cache,target=/build/nestri/target \
+    cargo build --release --workspace && \
+    mkdir -p /artifacts/nestri/usr/bin /artifacts/nestri/usr/lib \
+             /artifacts/nestri/usr/share/vulkan/implicit_layer.d && \
+    install -Dm755 target/release/nescope  /artifacts/nestri/usr/bin/nescope && \
+    install -Dm755 target/release/neshub   /artifacts/nestri/usr/bin/neshub && \
+    install -Dm755 target/release/neswire  /artifacts/nestri/usr/bin/neswire && \
+    install -Dm755 target/release/libnescapture_layer.so \
+        /artifacts/nestri/usr/lib/libnescapture_layer.so && \
+    install -Dm644 apps/nescapture/manifest/VK_LAYER_nescapture.json \
+        /artifacts/nestri/usr/share/vulkan/implicit_layer.d/VK_LAYER_nescapture.json && \
+    find /artifacts/nestri -type f -printf '/%P\n' > /artifacts/nestri/.manifest
+
+
+# ───────────────────────────────────────────────────────────
+#  os-base — the Artix rootfs itself
+#
+#  `FROM artixlinux/artixlinux:base-openrc` directly, and `pacman -S` as plain
+#  RUN steps — not a privileged host `chroot` into a hand-extracted tarball,
+#  which would need /proc, /sys and /dev bind-mounted in first (they don't
+#  exist inside a chroot target until something puts them there). A
+#  Dockerfile RUN step already executes inside a real container with its own
+#  /proc, /sys, /dev, so there is no bind-mount step to write at all.
+# ───────────────────────────────────────────────────────────
+FROM docker.io/artixlinux/artixlinux:base-openrc AS os-base
+
+RUN pacman -Syu --noconfirm --needed \
+        base openrc udev dbus dbus-openrc \
+        iptables iproute2 \
+        mesa libglvnd libdrm libepoxy libxxf86vm libinput wayland \
+        expat zlib llvm-libs elfutils libva shaderc vulkan-icd-loader \
+        pixman libxkbcommon xcb-util-keysyms xorg-xwayland \
+        pipewire pipewire-audio wireplumber dbus logrotate opus \
+    && pacman -Scc --noconfirm
+
+# groupadd -f so this is idempotent whether or not udev's rules already
+# created these.
+RUN groupadd -f audio && groupadd -f video && groupadd -f input && groupadd -f render && \
+    useradd -m -u 1000 -s /bin/bash nestri && \
+    for g in audio video input render; do gpasswd -a nestri "$g" >/dev/null; done
+
+
+# ───────────────────────────────────────────────────────────
+#  runtime — everything common to debug and prod
+# ───────────────────────────────────────────────────────────
+FROM os-base AS runtime
+
+# This is what GHCR actually uses to connect a pushed image back to its
+# repo — not a setting to toggle after the fact, a label the image has to
+# carry. Without it a manually-pushed image shows no "used by" repo on its
+# package page even though this Dockerfile is exactly what built it.
+LABEL org.opencontainers.image.source="https://github.com/nestrilabs/nestri"
+
+# Our own builds, overlaid on the distro's mesa. The distro package landed
+# first (above) so every runtime dependency of *a* Mesa is present and
+# correctly versioned; this overwrites its .so files with ours.
+#
+# COPY --from runs as root inside this build with no invoking-user uid to
+# stamp onto / or /usr/bin, unlike a host-side `podman cp` + `cp -a` — so
+# there is no ownership-sanity-check to write here. Nothing to catch, on
+# purpose, not an oversight.
+COPY --from=mesa-build   /artifacts/mesa/.manifest   /tmp/mesa.manifest
+COPY --from=nestri-build /artifacts/nestri/.manifest /tmp/nestri.manifest
+RUN cat /tmp/mesa.manifest /tmp/nestri.manifest > /tmp/.strip-manifest && \
+    rm -f /tmp/mesa.manifest /tmp/nestri.manifest
+COPY --from=mesa-build   /artifacts/mesa   /
+COPY --from=nestri-build /artifacts/nestri /
+RUN ldconfig
+
+COPY build/etc/ /etc/
+RUN chmod +x /etc/init.d/*
+
+# dbus-session, pipewire and wireplumber carry no conf.d of their own — they
+# just want the shared environment, so their conf.d is a symlink to it rather
+# than a copy. nescope, neshub and neswire are deliberately absent from this
+# loop: each has a conf.d file of its own (already landed by the COPY above)
+# that sources nestri-user-env, because each needs settings the shared file
+# does not carry. Symlinking them here would overwrite those.
+RUN for svc in dbus-session pipewire wireplumber; do \
+        ln -sf nestri-user-env "/etc/conf.d/${svc}"; \
+    done
+
+RUN echo nesbox > /etc/hostname && dbus-uuidgen --ensure=/etc/machine-id
+
+# Session mount points. The guest root is read-only at runtime, so a runtime
+# mkdir gets EROFS and takes a service down before it starts — these have to
+# already exist in the image.
+RUN mkdir -p /nestri/install /nestri/user /nestri/work /nestri/game /nestri/logs && \
+    chmod 0755 /nestri /nestri/install /nestri/user /nestri/work /nestri/game /nestri/logs && \
+    mkdir -p /dev/shm && chmod 1777 /dev/shm && \
+    rm -f /etc/network/interfaces
+
+# Serial console: the only way into a guest that will not boot.
+RUN rm -f /etc/inittab && \
+    ln -sf agetty /etc/init.d/agetty.hvc0 && \
+    { grep -qx hvc0 /etc/securetty || echo hvc0 >> /etc/securetty; }
+
+# Every init.d script calling nestri_export_env needs a conf.d that actually
+# defines it. Worth a build-time check: the failure at runtime is nearly
+# invisible — OpenRC sources the script, the undefined function is a
+# "command not found" on stderr, sourcing still returns 0, and the service
+# starts anyway with HOME and every XDG_* unset.
+RUN missing=""; \
+    for svc_script in /etc/init.d/*; do \
+        grep -qE '^[[:space:]]*nestri_export_env\b' "$svc_script" 2>/dev/null || continue; \
+        svc="$(basename "$svc_script")"; \
+        . "/etc/conf.d/$svc" >/dev/null 2>&1; \
+        command -v nestri_export_env >/dev/null 2>&1 || missing="$missing $svc"; \
+    done; \
+    [ -z "$missing" ] || { echo "init scripts call nestri_export_env with no conf.d providing it:$missing" >&2; exit 1; }
+
+# ── OpenRC service registration ──
+# sysinit
+RUN rc-update add devfs sysinit && \
+    rc-update add dmesg sysinit && \
+    rc-update add udev sysinit && \
+    rc-update add udev-trigger sysinit && \
+    (rc-update del kmod-static-nodes sysinit || true)
+
+# boot — guest-net replaces the distro's networking scripts entirely; it
+# declares `provide net` and brings up lo itself.
+RUN (rc-update del networking boot || true) && \
+    (rc-update del network-async boot || true) && rm -f /etc/init.d/network-async && \
+    rc-update add guest-net boot && \
+    (rc-update del net.lo boot || true) && \
+    (rc-update del netmount boot || true) && \
+    (rc-update del netmount default || true) && \
+    rc-update add hostname boot && \
+    rc-update add xdg-runtime boot && \
+    rc-update add cgroups boot && \
+    (rc-update del syslog boot || true)
+
+# Boot-runlevel services with nothing to do in a freshly-built microVM: no
+# physical console, no swap, and fsck would be checking a filesystem nobody
+# has touched.
+RUN for svc in fsck keymaps save-keymaps termencoding save-termencoding swap binfmt seedrng hwclock swclock; do \
+        (rc-update del "$svc" boot || true); \
+        (rc-update del "$svc" shutdown || true); \
+    done
+
+# default — the user-facing stack. nescope is registered in plain-compositor
+# mode (no payload after `--`): it comes up and waits for something to
+# connect. Actually starting a payload is nesinit's job, and nesinit is not
+# open code yet — see build/README.md.
+RUN rc-update add agetty.hvc0 default && \
+    for n in 1 2 3 4 5 6; do (rc-update del "agetty.tty${n}" default || true); done && \
+    rc-update add dbus default && \
+    rc-update add dbus-session default && \
+    rc-update add pipewire default && \
+    rc-update add wireplumber default && \
+    rc-update add neshub default && \
+    rc-update add neswire default && \
+    rc-update add nescope default && \
+    rm -f /etc/init.d/shared-root && (rc-update del shared-root boot || true)
+
+
+# ───────────────────────────────────────────────────────────
+#  runtime_prod — the default: `make build`
+# ───────────────────────────────────────────────────────────
+FROM runtime AS runtime_prod
+
+RUN passwd -l root
+COPY build/etc/conf.d/agetty.hvc0.prod /etc/conf.d/agetty.hvc0
+
+RUN while IFS= read -r f; do \
+        [ -f "$f" ] && strip --strip-unneeded "$f" 2>/dev/null || true; \
+    done < /tmp/.strip-manifest; \
+    rm -rf /tmp/.strip-manifest /var/cache/pacman/pkg/* /tmp/* /root/.cache \
+        /usr/share/man /usr/share/doc /usr/share/locale \
+        /usr/lib/cmake /usr/lib/pkgconfig /usr/share/pkgconfig /usr/include
+
+RUN echo "NESTRI_STAGE=runtime_prod" >> /etc/os-release
+
+
+# ───────────────────────────────────────────────────────────
+#  runtime_debug — `make build-debug`
+# ───────────────────────────────────────────────────────────
+FROM runtime AS runtime_debug
+
+RUN pacman -Syu --noconfirm --needed vulkan-tools mesa-utils libva-utils && \
+    pacman -Scc --noconfirm
+RUN echo 'root:nestri' | chpasswd
+COPY build/etc/conf.d/agetty.hvc0.debug /etc/conf.d/agetty.hvc0
+
+RUN echo "NESTRI_STAGE=runtime_debug" >> /etc/os-release

build/Makefile

@@ -0,0 +1,66 @@
+SHELL := /bin/bash
+.PHONY: build build-debug image image-debug clean help
+
+CONTAINER_RT := $(shell command -v docker 2>/dev/null || command -v podman 2>/dev/null)
+ifeq ($(CONTAINER_RT),)
+$(error "Neither docker nor podman found in PATH")
+endif
+
+# The Dockerfile COPYs from apps/ and crates/, so the build context is the
+# repo root, not this directory — same reason borealis's build/ *is* its own
+# context: here the guest source lives one level up instead of inside build/.
+CONTEXT      := ..
+# `ghcr.io/nestrilabs/nestri/base` (a package name with a `/` in it, matching
+# how every other image this org has published is named) is a deliberate
+# name, not just a tag: this is the image other builds start FROM —
+# nesbox's jailer image extracts Mesa/virgl from it to keep the guest and
+# host sides of the virtio-gpu native-context protocol on the same patched
+# Mesa, and closed downstream builds layer Proton/Steam on top of it
+# elsewhere. `runtime_prod`/`runtime_debug` already are exactly that: distro
+# packages plus our own Mesa/nestri artifacts overlaid on top, nothing
+# stripped that a downstream COPY --from= would miss — no separate
+# unstripped tag is needed for this.
+#
+# The registry host is part of the name on purpose, including for local
+# builds: a bare `nestrilabs/nestri` has no host, so anyone who pulls
+# instead of building locally resolves it against Docker Hub by default,
+# where it does not exist. One name, always pullable, beats a local-only
+# short name and a different published one.
+IMAGE_NAME   := ghcr.io/nestrilabs/nestri/base
+OUTPUT_DIR   := output
+ROOTFS_SIZE  ?= 5G
+FORCE_REBUILD ?=
+
+build:
+	DOCKER_BUILDKIT=1 $(CONTAINER_RT) build $(if $(FORCE_REBUILD),--no-cache,) \
+		-f Dockerfile -t $(IMAGE_NAME):latest --target runtime_prod $(CONTEXT)
+
+build-debug:
+	DOCKER_BUILDKIT=1 $(CONTAINER_RT) build $(if $(FORCE_REBUILD),--no-cache,) \
+		-f Dockerfile -t $(IMAGE_NAME):debug --target runtime_debug $(CONTEXT)
+
+# Not `sudo make image`/sudo'd in here: mkimage.sh runs as you and escalates
+# only the specific commands that need root. Under rootless Podman, `make
+# build` stores the image in *your* storage — sudo-ing the whole script would
+# have root's podman look for that tag in its own, separate storage and fail
+# to find it.
+image: build
+	@mkdir -p $(OUTPUT_DIR)
+	bash scripts/mkimage.sh $(IMAGE_NAME):latest $(OUTPUT_DIR)/rootfs.ext4 $(ROOTFS_SIZE)
+
+image-debug: build-debug
+	@mkdir -p $(OUTPUT_DIR)
+	bash scripts/mkimage.sh $(IMAGE_NAME):debug $(OUTPUT_DIR)/rootfs-debug.ext4 $(ROOTFS_SIZE)
+
+clean:
+	rm -rf $(OUTPUT_DIR)
+
+help:
+	@echo "Usage:"
+	@echo "  make build              Build the runtime_prod container image"
+	@echo "  make build-debug        Build the runtime_debug container image"
+	@echo "  make image              Build + pack runtime_prod into output/rootfs.ext4"
+	@echo "  make image-debug        Build + pack runtime_debug into output/rootfs-debug.ext4"
+	@echo "  make clean               Remove output/"
+	@echo "  make FORCE_REBUILD=1 ...  Rebuild from scratch, no layer cache"
+	@echo "  make ROOTFS_SIZE=8G image  Override the packed image size (default 5G)"

build/README.md

@@ -0,0 +1,90 @@
+# build/ — the guest rootfs
+
+Builds a bootable Artix/OpenRC image for the box's virtio-blk root: Mesa
+(virtio-gpu native context) plus the four open guest components —
+[`nescope`](../apps/nescope), [`neshub`](../apps/neshub),
+[`neswire`](../apps/neswire), [`nescapture`](../apps/nescapture) — laid out
+the way [borealis](https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/main/project-borealis)
+lays out its `build/`: one big multi-stage `Dockerfile`, `--target` picks the
+flavor, `etc/` holds the files that get overlaid onto the image verbatim.
+
+```
+build/
+├── Dockerfile         everything, in stages: mesa-build, nestri-build,
+│                       os-base, runtime, runtime_prod, runtime_debug
+├── etc/                overlaid onto the image's /etc as-is
+├── scripts/
+│   └── mkimage.sh      docker export → raw ext4, for nesbox's virtio-blk
+├── Makefile
+└── output/             `make image` writes here (gitignored)
+```
+
+```sh
+make build          # docker build --target runtime_prod   → ghcr.io/nestrilabs/nestri/base:latest
+make build-debug    # docker build --target runtime_debug  → ghcr.io/nestrilabs/nestri/base:debug
+make image          # + pack into output/rootfs.ext4
+make image-debug    # + pack into output/rootfs-debug.ext4
+```
+
+## Design notes
+
+Three things worth knowing about how this is put together:
+
+1. **No privileged host chroot.** A bare `chroot` into a hand-extracted
+   rootfs needs `/proc`, `/sys`, `/dev` bind-mounted in first — they don't
+   exist inside a chroot target until something puts them there. `os-base`
+   here is `FROM artixlinux/artixlinux:base-openrc` directly, with
+   `pacman -S` as plain `RUN` steps — a Docker build step already runs
+   inside a real container with its own `/proc`, `/sys`, `/dev`, so that
+   whole bind-mount mechanism has nothing to do.
+
+2. **No host-side ownership bug to guard against.** `COPY --from=` runs as
+   root inside the build with no host user in the loop, so there's no
+   invoking-user uid getting stamped onto `/`, `/usr/bin`, or anywhere else
+   a build step touches — a failure mode some overlay approaches need an
+   explicit sanity check for doesn't exist here to check for.
+
+3. **One `cargo build --release --workspace`, not one stage per binary.**
+   `nescope`, `neshub`, `neswire` and `nescapture` share one Cargo workspace
+   and one `Cargo.lock` — a BuildKit cache mount on `target/` gives cargo's
+   own incremental compiler per-crate isolation without needing a separate
+   Docker stage (and a separate full rebuild of `nesprotocol`) per binary.
+
+**What is deliberately not here: Proton, and Valve's `steamclient.so`.**
+`nestri/CLAUDE.md` is explicit — *"Nothing closed may enter this repo. Not
+source, not a dependency, not a directory that 'looked convenient'."* Both
+are closed. `runtime_prod` from this Dockerfile — tagged
+`ghcr.io/nestrilabs/nestri/base:latest` — is a complete, bootable, Steam-less guest image,
+and also the shared foundation other builds start from: nesbox's jailer
+image (see `nesbox/build/`) extracts Mesa and virglrenderer from it so the
+guest and host sides of the virtio-gpu native-context protocol never drift
+apart. Whatever layers Proton and the Steam client on top of it is a closed
+build outside this repo, by design — not something this repo names, links
+to, or depends on.
+
+## The nesinit gap
+
+Nothing in this image starts a payload. The old `nestri-guest-hub` did that
+— per its own commit message, the open `neshub` *"loses `--proton`,
+`--steamclient-so`, `--root` and the game uid/gid, and no longer ends by
+handing the process to a controller... Deciding when the box is finished
+belongs to `nesinit`."* `nesinit` — the guest init/session-supervisor that
+would actually launch `nescope -- <payload>` and power the box down — is
+referenced in commit messages and `nesbox/PROGRESS.md` but does not exist as
+open code in either repo.
+
+So `/etc/init.d/nescope` here starts nescope in **plain-compositor mode**
+(no command after `--`): it comes up, provides the Wayland/X11 environment,
+and waits for something to connect. That makes the image genuinely bootable
+and testable — `neshub`, `neswire`, `nescope` all come up under OpenRC and
+you get a real Wayland socket to point a client at — but running an actual
+game is still nesinit's job, and nesinit isn't part of this build. Whoever
+picks that up next should read `apps/neshub/README.md`'s "What it does not
+do" section first.
+
+## Network defaults
+
+`/etc/init.d/guest-net` reads `nestri.ip=`/`nestri.gw=` off the kernel
+command line, falling back to `172.30.0.2/24` via `172.30.0.1` if neither is
+set — nesbox's own default tap addressing. Keep these in step if that
+changes on the nesbox side.

build/etc/conf.d/agetty.hvc0.debug

@@ -0,0 +1,3 @@
+baud="115200"
+term_type="vt100"
+agetty_options="--autologin root --noclear"

build/etc/conf.d/agetty.hvc0.prod

@@ -0,0 +1,3 @@
+baud="115200"
+term_type="vt100"
+agetty_options="--noclear"

build/etc/conf.d/nescope

@@ -0,0 +1,16 @@
+# Configuration for nescope, the headless compositor.
+#
+# Sources nestri-user-env rather than symlinking it, for the same reason
+# neshub and neswire do.
+. /etc/conf.d/nestri-user-env
+
+RUST_LOG="${RUST_LOG:-nescope=info}"
+export RUST_LOG
+
+# Started in plain-compositor mode by /etc/init.d/nescope (no command after
+# `--`): it comes up and waits for something to connect rather than wrapping
+# a payload. Starting an actual payload — a game, a desktop — is nesinit's
+# job, and nesinit is not open code yet. See build/README.md.
+NESCOPE_SOCKET="${NESCOPE_SOCKET:-nescope-0}"
+NESCOPE_INPUT_IPC="${NESCOPE_INPUT_IPC:-/tmp/nestri-input.sock}"
+export NESCOPE_SOCKET NESCOPE_INPUT_IPC

build/etc/conf.d/neshub

@@ -0,0 +1,18 @@
+# Configuration for neshub, the media hub.
+#
+# Not a symlink to nestri-user-env like pipewire and friends: neshub wants a
+# setting of its own, so it sources that file rather than replacing it — same
+# pattern as nescope and neswire below.
+. /etc/conf.d/nestri-user-env
+
+# What neshub logs, and nothing else.
+#
+# Scoped and exported for the reason spelled out at length in the old
+# nestri-guest-hub conf.d this replaces: an unscoped `RUST_LOG=info` turns on
+# every crate linked in, iroh included, and OpenRC hands a service its own
+# environment, not the shell's locals — an unexported variable here goes
+# nowhere.
+#
+# Overridable, so a bad boot can be re-run with more without a rebuild.
+RUST_LOG="${RUST_LOG:-neshub=info}"
+export RUST_LOG

build/etc/conf.d/nestri-user-env

@@ -0,0 +1,30 @@
+HOME="/home/nestri"
+USER="nestri"
+LOGNAME="nestri"
+XDG_RUNTIME_DIR="/run/user/1000"
+XDG_CONFIG_HOME="/home/nestri/.config"
+XDG_DATA_HOME="/home/nestri/.local/share"
+XDG_CACHE_HOME="/home/nestri/.cache"
+XDG_STATE_HOME="/home/nestri/.local/state"
+XDG_DATA_DIRS="/usr/local/share:/usr/share"
+XDG_SESSION_TYPE="wayland"
+XDG_SESSION_DESKTOP="nestri"
+DBUS_SESSION_BUS_ADDRESS="unix:path=/run/user/1000/bus"
+
+# Driver forcing, mirrored from /etc/profile.d/nestri-env.sh. That file only
+# runs for login shells, and nothing here is a login shell — every service
+# below runs from OpenRC. Capture happens through a Vulkan layer, so a
+# process that reached the GPU via native OpenGL would render fine and
+# capture nothing; zink is what makes such a process capturable at all.
+# These are load-bearing. Keep them in step with the profile.d copy.
+#__GLX_VENDOR_LIBRARY_NAME="mesa"
+#MESA_LOADER_DRIVER_OVERRIDE="zink"
+#GALLIUM_DRIVER="zink"
+
+nestri_export_env() {
+    export HOME USER LOGNAME
+    export XDG_RUNTIME_DIR XDG_CONFIG_HOME XDG_DATA_HOME XDG_CACHE_HOME XDG_STATE_HOME
+    export XDG_DATA_DIRS XDG_SESSION_TYPE XDG_SESSION_DESKTOP
+    export DBUS_SESSION_BUS_ADDRESS
+    #export __GLX_VENDOR_LIBRARY_NAME MESA_LOADER_DRIVER_OVERRIDE GALLIUM_DRIVER
+}

build/etc/conf.d/neswire

@@ -0,0 +1,32 @@
+# Configuration for the audio wire.
+#
+# Not a symlink to nestri-user-env like pipewire and friends, for the same
+# reason neshub is not: it needs a setting of its own -- and it still wants
+# that file's environment, so it sources it rather than replacing it.
+. /etc/conf.d/nestri-user-env
+
+# What neswire logs, and nothing else.
+#
+# Without this neswire is *silent* -- it starts, fails, and exits leaving an
+# empty log, which is indistinguishable from never having been started at
+# all. That ambiguity is the reason this file exists.
+#
+# Scoped, and `export`ed, for the reasons spelled out at length in
+# conf.d/neshub: an unscoped `info` turns on every linked crate, and an
+# unexported one reaches the service's shell and not the service.
+#
+# Overridable, so a bad boot can be re-run with more without a rebuild.
+RUST_LOG="${RUST_LOG:-neswire=info}"
+export RUST_LOG
+
+# neswire's own defaults, spelled out rather than inherited.
+#
+# All four are clap args with defaults (`neswire --help`), so the service
+# works without them. They are here because the IPC path is a contract with
+# neshub -- it reads this socket -- and a contract that lives only inside two
+# binaries' default values is one nobody can check.
+NESWIRE_IPC_PATH="/tmp/nestri-audio.sock"
+NESWIRE_CHANNELS="2"
+NESWIRE_PACKET_DURATION_MS="5"
+NESWIRE_BITRATE_PER_CHANNEL="64"
+export NESWIRE_IPC_PATH NESWIRE_CHANNELS NESWIRE_PACKET_DURATION_MS NESWIRE_BITRATE_PER_CHANNEL

build/etc/fstab

@@ -0,0 +1,29 @@
+/dev/vda    /          ext4     rw,relatime              0 1
+devtmpfs    /dev       devtmpfs rw,nosuid                0 0
+proc        /proc      proc     rw,nosuid,nodev,noexec   0 0
+sysfs       /sys       sysfs    rw,nosuid,nodev,noexec   0 0
+tmpfs       /tmp       tmpfs    rw,nosuid,nodev,size=64M 0 0
+tmpfs       /run       tmpfs    rw,nosuid,nodev,size=32M,mode=0755 0 0
+tmpfs       /var/log   tmpfs    rw,nosuid,nodev,size=16M 0 0
+# POSIX shared memory. devtmpfs does not provide it and nothing else mounts it,
+# so without this entry /dev/shm does not exist at all and `shm_open` fails.
+#
+# PipeWire itself gets by: it allocates buffers with memfd_create and only
+# falls back to /dev/shm. Kept as a precaution for anything else that uses
+# POSIX shm/semaphores directly — Proton is the known example, and it is not
+# part of this image yet (see build/README.md), but a failure here is silent
+# rather than fatal, so it costs nothing to have ready.
+#
+# `nosuid,nodev` and a size cap because everything a game can write to should
+# have both.
+tmpfs       /dev/shm   tmpfs    rw,nosuid,nodev,size=256M 0 0
+# The guest's logs, on a host directory that outlives the VM.
+#
+# Here rather than mounted by a service, because the failures worth reading
+# are the ones that happen *before* anything else has mounted something — a
+# log directory that appears only after a successful start cannot record an
+# unsuccessful one. The tag is fixed by nessh, so plain fstab works.
+#
+# `nofail` because a VM started without the share still has to boot: that is
+# how somebody gets a shell to find out why it has no share.
+logs        /nestri/logs virtiofs rw,nofail                0 0

build/etc/init.d/dbus-session

@@ -0,0 +1,33 @@
+#!/sbin/openrc-run
+
+description="D-Bus session bus for nestri user"
+
+nestri_export_env
+
+command="/usr/bin/dbus-daemon"
+command_args="--session --address=unix:path=/run/user/1000/bus --nofork --nopidfile --print-address"
+command_user="nestri:nestri"
+command_background="yes"
+pidfile="/run/nestri/dbus-session.pid"
+
+depend() {
+    need xdg-runtime dbus
+    before pipewire wireplumber
+}
+
+start_pre() {
+    checkpath -d -m 0755 -o "nestri:nestri" /run/nestri
+    if [ -e "/run/user/1000/bus" ]; then
+        ewarn "Removing stale bus socket"
+        rm -f "/run/user/1000/bus"
+    fi
+}
+
+start_post() {
+    local i=0
+    while [ ! -S /run/user/1000/bus ] && [ $i -lt 20 ]; do
+        sleep 0.1
+        i=$((i+1))
+    done
+    [ -S /run/user/1000/bus ] || { eerror "Bus didn't appear"; return 1; }
+}

build/etc/init.d/dbus-system

@@ -0,0 +1,19 @@
+#!/sbin/openrc-run
+
+description="D-Bus system message bus"
+
+command="/usr/bin/dbus-daemon"
+command_args="--system --nofork --nopidfile"
+command_background="yes"
+pidfile="/run/dbus/dbus.pid"
+
+depend() {
+    need localmount xdg-runtime
+    before pipewire
+}
+
+start_pre() {
+    checkpath -d -m 0755 -o root:root /run/dbus
+    checkpath -d -m 0755 -o messagebus:messagebus /var/run/dbus 2>/dev/null || true
+    dbus-uuidgen --ensure=/var/lib/dbus/machine-id
+}

build/etc/init.d/guest-net

@@ -0,0 +1,92 @@
+#!/sbin/openrc-run
+
+description="Configure the guest's network to match the host's tap"
+
+# Overridden from /etc/conf.d/guest-net if present. These defaults match
+# nesbox's own defaults; if you change the `network` section in the VM's
+# JSON, change these to match.
+: ${GUEST_IFACE:=eth0}
+: ${GUEST_IP:=172.30.0.2}
+: ${GUEST_PREFIX:=24}
+: ${GUEST_GATEWAY:=172.30.0.1}
+
+depend() {
+    need localmount
+    provide net
+    keyword -shutdown
+}
+
+# Read one `nestri.<key>=<value>` from the kernel command line.
+#
+# The address has to come from somewhere per-boot, because the alternative --
+# baking it into the image -- makes every guest built from that image the
+# same host on the network. Two sandboxes then collide the moment they run
+# together.
+#
+# `nestri.`-prefixed rather than the kernel's own `ip=`: that one needs
+# CONFIG_IP_PNP and exists to configure NFS root, and the prefix makes it
+# obvious whose parameter this is.
+cmdline_value() {
+    local key="$1" word
+    for word in $(cat /proc/cmdline 2>/dev/null); do
+        case "$word" in
+            "nestri.${key}="*) printf '%s' "${word#nestri.${key}=}"; return 0 ;;
+        esac
+    done
+    return 1
+}
+
+start() {
+    ebegin "Bringing up loopback"
+    ip link set lo up
+    eend $?
+
+    # The command line wins over conf.d when it says anything, and conf.d is
+    # the fallback so a hand-written VM config with no parameters keeps
+    # working -- which is how a guest gets debugged.
+    local source="/etc/conf.d/guest-net"
+    local cmdline_ip
+    if cmdline_ip="$(cmdline_value ip)"; then
+        # Accepts address/prefix; a bare address keeps the configured prefix
+        # rather than guessing one.
+        case "$cmdline_ip" in
+            */*)
+                GUEST_IP="${cmdline_ip%%/*}"
+                GUEST_PREFIX="${cmdline_ip##*/}"
+                ;;
+            *)  GUEST_IP="$cmdline_ip" ;;
+        esac
+        source="kernel command line"
+    fi
+
+    local cmdline_gw
+    if cmdline_gw="$(cmdline_value gw)"; then
+        GUEST_GATEWAY="$cmdline_gw"
+        source="kernel command line"
+    fi
+
+    # The VM may have been started with no network device at all, which is a
+    # perfectly good configuration. Do not fail the boot over it.
+    if [ ! -e "/sys/class/net/${GUEST_IFACE}" ]; then
+        einfo "no ${GUEST_IFACE}: this VM has no network device"
+        return 0
+    fi
+
+    # Says which source won, because "the address is wrong" and "the address
+    # came from somewhere unexpected" look identical from inside the guest.
+    ebegin "Configuring ${GUEST_IFACE} as ${GUEST_IP}/${GUEST_PREFIX} via ${GUEST_GATEWAY} (from ${source})"
+    # `replace` rather than `add` so a restart is not an error.
+    ip link set "${GUEST_IFACE}" up &&
+        ip addr replace "${GUEST_IP}/${GUEST_PREFIX}" dev "${GUEST_IFACE}" &&
+        ip route replace default via "${GUEST_GATEWAY}" dev "${GUEST_IFACE}"
+    eend $? "could not configure ${GUEST_IFACE}"
+}
+
+stop() {
+    if [ -e "/sys/class/net/${GUEST_IFACE}" ]; then
+        ebegin "Bringing down ${GUEST_IFACE}"
+        ip link set "${GUEST_IFACE}" down
+        eend 0
+    fi
+    return 0
+}

build/etc/init.d/nescope

@@ -0,0 +1,33 @@
+#!/sbin/openrc-run
+
+description="Nestri headless compositor"
+
+nestri_export_env
+
+: "${NESTRI_UID:=1000}"
+: "${NESTRI_USER:=nestri}"
+
+command="/usr/bin/nescope"
+# No command after `--`: plain-compositor mode. nescope comes up and waits
+# for something to connect rather than wrapping a payload — starting one is
+# nesinit's job, and nesinit is not open code yet. See build/README.md.
+command_user="${NESTRI_USER}:${NESTRI_USER}"
+command_background="yes"
+pidfile="/run/nestri/nescope.pid"
+output_log="/nestri/logs/nescope.log"
+error_log="/nestri/logs/nescope.log"
+respawn="yes"
+respawn_delay="2"
+respawn_max="2"
+
+export XDG_RUNTIME_DIR="/run/user/${NESTRI_UID}"
+
+depend() {
+    need xdg-runtime
+    use neshub
+    after xdg-runtime
+}
+
+start_pre() {
+    checkpath -d -m 0755 -o "${NESTRI_USER}:${NESTRI_USER}" /run/nestri
+}

build/etc/init.d/neshub

@@ -0,0 +1,39 @@
+#!/sbin/openrc-run
+
+description="Nestri media hub"
+
+nestri_export_env
+
+: "${NESTRI_UID:=1000}"
+: "${NESTRI_USER:=nestri}"
+
+command="/usr/bin/neshub"
+# Unprivileged. The old nestri-guest-hub ran as root and mounted the
+# session's filesystem itself; the open neshub does neither — per its own
+# README it only muxes the Unix sockets the other components dial into one
+# QUIC endpoint. Whatever ends up owning session mounts (nesinit, presumably)
+# is a separate, still-closed piece.
+command_user="${NESTRI_USER}:${NESTRI_USER}"
+command_background="yes"
+pidfile="/run/nestri/neshub.pid"
+
+# Where neshub's output goes. /nestri/logs is a virtiofs share mounted from
+# /etc/fstab at boot, before this service starts, so a hub that fails
+# immediately still leaves a record, and the record survives the VM.
+output_log="/nestri/logs/neshub.log"
+error_log="/nestri/logs/neshub.log"
+respawn="yes"
+respawn_delay="2"
+respawn_max="2"   # NO infinite — if it fails, it fails for a reason
+
+export XDG_RUNTIME_DIR="/run/user/${NESTRI_UID}"
+
+depend() {
+    need xdg-runtime
+    use net
+    after xdg-runtime
+}
+
+start_pre() {
+    checkpath -d -m 0755 -o "${NESTRI_USER}:${NESTRI_USER}" /run/nestri
+}

build/etc/init.d/neswire

@@ -0,0 +1,93 @@
+#!/sbin/openrc-run
+
+description="Nestri pipewire audio sink"
+
+nestri_export_env
+
+: "${NESTRI_UID:=1000}"
+: "${NESTRI_USER:=nestri}"
+
+command="/usr/bin/neswire"
+command_user="${NESTRI_USER}:${NESTRI_USER}"
+command_background="yes"
+pidfile="/run/nestri/neswire.pid"
+output_log="/nestri/logs/neswire.log"
+error_log="/nestri/logs/neswire.log"
+respawn="yes"
+respawn_delay="2"
+respawn_max="2"
+
+export XDG_RUNTIME_DIR="/run/user/${NESTRI_UID}"
+export DBUS_SESSION_BUS_ADDRESS="unix:path=/run/user/${NESTRI_UID}/bus"
+
+depend() {
+    # wireplumber is a hard dependency, not a nicety: start_post below pins
+    # the default sink through the `default` metadata object, and
+    # WirePlumber is what owns that object. Started concurrently, the pin
+    # lands in an object pw-metadata created itself, which is destroyed the
+    # moment it exits.
+    need xdg-runtime dbus dbus-session pipewire wireplumber
+    use neshub
+    after pipewire wireplumber neshub
+}
+
+start_pre() {
+    checkpath -d -m 0755 -o "${NESTRI_USER}:${NESTRI_USER}" /run/nestri
+}
+
+# Point the graph at neswire's sink, by name.
+#
+# `neswire` registers itself as media.class = Audio/Sink, node.name = neswire
+# ("Neswire Cloud Gaming Audio Sink"). With the hardware monitors off it is
+# the only sink, so WirePlumber's find-best hook should land on it anyway --
+# this makes it explicit rather than a consequence of there being nothing
+# else, so adding a second sink later cannot silently steal the default.
+#
+# `default.configured.audio.sink` is the metadata WirePlumber's find-selected
+# hook reads, and it takes a name; `wpctl set-default` takes a numeric object
+# id that changes every boot, which is why this uses pw-metadata instead.
+#
+# Not fatal if it fails: find-best still has one candidate. A game playing
+# into the wrong sink is silent, and a warning here is the only place that
+# would say so.
+start_post() {
+    local i=0
+    while [ $i -lt 50 ]; do
+        pw-dump 2>/dev/null | grep -q '"node.name": "neswire"' && break
+        sleep 0.1
+        i=$((i+1))
+    done
+    if ! pw-dump 2>/dev/null | grep -q '"node.name": "neswire"'; then
+        ewarn "neswire started but its sink never appeared in the graph"
+        return 0
+    fi
+
+    # Wait for WirePlumber to own the `default` metadata before writing to it.
+    #
+    # `need wireplumber` only guarantees its script returned, not that it has
+    # built its objects. Writing too early is silently useless rather than an
+    # error: pw-metadata creates the object, sets the key, exits 0, and the
+    # object dies with the client. So wait for the object to exist, and say
+    # so if it never does.
+    i=0
+    while [ $i -lt 50 ]; do
+        pw-metadata -n default >/dev/null 2>&1 && break
+        sleep 0.1
+        i=$((i+1))
+    done
+    if ! pw-metadata -n default >/dev/null 2>&1; then
+        ewarn "no 'default' metadata: WirePlumber is not running, sink not pinned"
+        return 0
+    fi
+
+    pw-metadata -n default 0 default.configured.audio.sink '{ "name": "neswire" }' \
+        >/dev/null 2>&1
+
+    # Read it back. A write that did not stick is the failure this whole
+    # sequence exists to catch, and it is invisible unless checked.
+    if pw-metadata -n default 2>/dev/null | grep -q "neswire"; then
+        einfo "default sink pinned to neswire"
+    else
+        ewarn "pinned neswire as default sink but it did not stick"
+    fi
+}

build/etc/init.d/pipewire

@@ -0,0 +1,45 @@
+#!/sbin/openrc-run
+
+description="PipeWire multimedia daemon (system mode for nestri)"
+
+nestri_export_env
+
+: "${NESTRI_UID:=1000}"
+: "${NESTRI_USER:=nestri}"
+
+command="/usr/bin/pipewire"
+command_user="${NESTRI_USER}:${NESTRI_USER}"
+command_background="yes"
+pidfile="/run/pipewire/pipewire.pid"
+
+export XDG_RUNTIME_DIR="/run/user/${NESTRI_UID}"
+export DBUS_SESSION_BUS_ADDRESS="unix:path=/run/user/${NESTRI_UID}/bus"
+
+depend() {
+    need xdg-runtime dbus
+    use dbus
+}
+
+start_pre() {
+    checkpath -d -m 0755 -o "${NESTRI_USER}:${NESTRI_USER}" /run/pipewire
+}
+
+# `need pipewire` only waits for this script to return, and with
+# command_background that is the moment start-stop-daemon forks -- not the
+# moment PipeWire is accepting connections. With rc_parallel="YES" every
+# client (wireplumber, neswire) then races the socket and a client that
+# loses simply exits.
+#
+# dbus-session already solved exactly this for the bus socket. Same shape
+# here.
+start_post() {
+    local i=0
+    while [ ! -S "/run/user/${NESTRI_UID}/pipewire-0" ] && [ $i -lt 50 ]; do
+        sleep 0.1
+        i=$((i+1))
+    done
+    [ -S "/run/user/${NESTRI_UID}/pipewire-0" ] || {
+        eerror "PipeWire socket never appeared"
+        return 1
+    }
+}

build/etc/init.d/wireplumber

@@ -0,0 +1,20 @@
+#!/sbin/openrc-run
+
+description="WirePlumber session manager for PipeWire"
+
+nestri_export_env
+
+: "${NESTRI_UID:=1000}"
+: "${NESTRI_USER:=nestri}"
+
+command="/usr/bin/wireplumber"
+command_user="${NESTRI_USER}:${NESTRI_USER}"
+command_background="yes"
+pidfile="/run/pipewire/wireplumber.pid"
+
+export XDG_RUNTIME_DIR="/run/user/${NESTRI_UID}"
+
+depend() {
+    need pipewire
+    after pipewire
+}

build/etc/init.d/xdg-runtime

@@ -0,0 +1,44 @@
+#!/sbin/openrc-run
+
+description="Create runtime directories (XDG_RUNTIME_DIR, X11 socket dir..)"
+
+NESTRI_UID="${NESTRI_UID:-1000}"
+NESTRI_USER="${NESTRI_USER:-nestri}"
+
+depend() {
+    need localmount
+    before dbus pipewire
+}
+
+start() {
+    ebegin "Preparing runtime directories"
+
+    if ! getent passwd "${NESTRI_USER}" >/dev/null 2>&1; then
+        eerror "User ${NESTRI_USER} does not exist"
+        return 1
+    fi
+
+    # Per-user XDG runtime dir
+    mkdir -p "/run/user/${NESTRI_UID}"
+    chown "${NESTRI_USER}:${NESTRI_USER}" "/run/user/${NESTRI_UID}"
+    chmod 0700 "/run/user/${NESTRI_UID}"
+
+    # X11 socket dir (Xwayland + any X clients expect this)
+    mkdir -p /tmp/.X11-unix
+    chown root:root /tmp/.X11-unix
+    chmod 1777 /tmp/.X11-unix
+
+    # ICE socket dir - some toolkits look for it
+    mkdir -p /tmp/.ICE-unix
+    chown root:root /tmp/.ICE-unix
+    chmod 1777 /tmp/.ICE-unix
+
+    eend $?
+}
+
+stop() {
+    ebegin "Removing runtime directories"
+    rm -rf "/run/user/${NESTRI_UID}"
+    # Don't rm /tmp/.X11-unix on stop - other things may be using it
+    eend 0
+}

build/etc/profile.d/nestri-env.sh

@@ -0,0 +1,27 @@
+# Nestri user environment — sourced for nestri user logins and su -
+if [ "$(id -u)" = "1000" ]; then
+    export XDG_RUNTIME_DIR="/run/user/1000"
+    export XDG_CONFIG_HOME="${HOME}/.config"
+    export XDG_DATA_HOME="${HOME}/.local/share"
+    export XDG_CACHE_HOME="${HOME}/.cache"
+    export XDG_STATE_HOME="${HOME}/.local/state"
+
+    export DBUS_SESSION_BUS_ADDRESS="unix:path=${XDG_RUNTIME_DIR}/bus"
+
+    # Portal backend selection. "GTK" matches xdg-desktop-portal-gtk.
+    # Once nescope supports wlr portals, change to "wlroots" or similar.
+    #export XDG_CURRENT_DESKTOP="${XDG_CURRENT_DESKTOP:-GTK}"
+    export XDG_SESSION_TYPE="${XDG_SESSION_TYPE:-wayland}"
+    export XDG_SESSION_DESKTOP="${XDG_SESSION_DESKTOP:-nestri}"
+
+    # Ensure proper VAAPI driver is used
+    #export LIBVA_DRIVER_NAME="radeonsi"
+
+    # Force zink usage for OpenGL -> Vulkan translation
+    #export __GLX_VENDOR_LIBRARY_NAME=mesa
+    #export MESA_LOADER_DRIVER_OVERRIDE=zink
+    #export GALLIUM_DRIVER=zink
+
+    # Ensure standard XDG dirs exist
+    mkdir -p "${XDG_CONFIG_HOME}" "${XDG_DATA_HOME}" "${XDG_CACHE_HOME}" "${XDG_STATE_HOME}" 2>/dev/null || true
+fi

build/etc/rc.conf

@@ -0,0 +1,27 @@
+# Nestri rootfs OpenRC config
+
+rc_parallel="YES"
+rc_depend_strict="NO"
+rc_interactive="NO"
+rc_shell_timeout="0"
+# Every service's start/fail line, on the host directory that outlives the VM.
+#
+# Without this a guest nobody can log into reports nothing about its own boot:
+# a service that was skipped because a dependency failed looks exactly like a
+# service that was never registered. /nestri/logs is a virtiofs share, so the
+# record survives the guest — see the fstab entry below.
+rc_logger="YES"
+rc_log_path="/nestri/logs/rc.log"
+rc_verbose="NO"
+
+# cgroup v2
+rc_cgroup_mode="unified"
+
+# Don't bother trying to set hostname twice
+rc_hotplug="!net.*"
+
+# Faster sulogin behavior on emergency
+rc_shell="/bin/sh"
+
+# Default umask
+umask 022

build/etc/resolv.conf

@@ -0,0 +1,2 @@
+nameserver 1.1.1.1
+nameserver 8.8.8.8

build/etc/wireplumber/wireplumber.conf.d/50-nestri.conf

@@ -0,0 +1,41 @@
+# WirePlumber, trimmed to what a microVM with no sound card actually needs.
+#
+# The goal is that `neswire` is the *only* Audio/Sink in the graph, so
+# default-node selection has exactly one candidate and cannot pick wrong.
+#
+# The "Dummy Output" (`auto_null`) sink is not disabled here, and no longer
+# needs to be: it came from pipewire-pulse's `module-always-sink`, and
+# pipewire-pulse is no longer installed. WirePlumber ships
+# scripts/fallback-sink.lua, which creates a node by the same name, but no
+# component in wireplumber.conf references it, so it never loads. If auto_null
+# ever comes back, it came back with pipewire-pulse -- the switch is
+# `pulse.cmd.always-sink = false` in a pipewire-pulse.conf.d drop-in, not
+# anything on this side.
+#
+# pipewire.conf's Dummy-Driver / Freewheel-Driver are a third thing again:
+# support.node.driver objects with no ports -- drivers, not sinks, so nothing
+# can play into them. Dummy-Driver is load-bearing here. With no ALSA hardware
+# it is what clocks the graph, and therefore what paces neswire's sink. Do not
+# disable it.
+
+wireplumber.profiles = {
+  main = {
+    # No sound card, no bluetooth adapter, no camera. These only exist to
+    # probe hardware this guest does not have; disabling them removes the
+    # only other source of sinks besides neswire.
+    hardware.audio = disabled
+    hardware.bluetooth = disabled
+    hardware.video-capture = disabled
+
+    # The guest root is read-only and every VM is built from the same image, so
+    # there is nothing to restore and nowhere to save. Left enabled, a stale
+    # state file is a second, invisible place that can pin a default sink --
+    # the exact failure this file exists to rule out.
+    #
+    # Equivalent to inheriting mixin.stateless, spelled out so it is greppable.
+    hooks.default-nodes.state = disabled
+    hooks.device.profile.state = disabled
+    hooks.device.routes.state = disabled
+    hooks.stream.state = disabled
+  }
+}

build/scripts/mkimage.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+# Pack a built container image into a raw ext4 disk for nesbox's virtio-blk.
+#
+# Docker/Buildx has no native "export a raw disk image" step, so this is the
+# one part of the pipeline that still has to run outside the Dockerfile.
+#
+# Run this as yourself, not under sudo. Only mkfs/mount/umount actually need
+# root, and those are escalated individually below — `sudo bash mkimage.sh`
+# for the whole script is exactly the wrong shape for rootless Podman: the
+# image `make build` produced lives in *your* rootless storage, and running
+# `podman create` as root afterwards looks in root's separate storage, where
+# the tag does not exist. `sudo -v` up front just avoids being prompted
+# mid-script for the escalated calls that follow.
+set -euo pipefail
+
+IMAGE="${1:?usage: mkimage.sh <image-tag> <output-path> [size]}"
+OUT="${2:?usage: mkimage.sh <image-tag> <output-path> [size]}"
+SIZE="${3:-5G}"
+
+if [[ "$(id -u)" -eq 0 ]]; then
+    echo "mkimage.sh should run as yourself, not root/sudo — see the comment at the top of this script" >&2
+    exit 1
+fi
+
+CONTAINER_RT="$(command -v docker || command -v podman || true)"
+[[ -n "$CONTAINER_RT" ]] || { echo "Neither docker nor podman found in PATH" >&2; exit 1; }
+
+sudo -v   # cache credentials once, rather than prompting mid-pipeline
+
+WORK="$(mktemp -d)"
+cleanup() {
+    mountpoint -q "$WORK/mnt" 2>/dev/null && sudo umount "$WORK/mnt"
+    rm -rf "$WORK"
+}
+trap cleanup EXIT
+
+echo "Exporting ${IMAGE}..."
+cid="$("$CONTAINER_RT" create "$IMAGE")"
+"$CONTAINER_RT" export "$cid" -o "$WORK/rootfs.tar"
+"$CONTAINER_RT" rm -f "$cid" >/dev/null
+
+echo "Creating ${SIZE} ext4 image at ${OUT}..."
+mkdir -p "$(dirname "$OUT")"
+truncate -s "$SIZE" "$OUT"
+sudo mkfs.ext4 -q -L nestri-root "$OUT"
+
+mkdir -p "$WORK/mnt"
+sudo mount -o loop "$OUT" "$WORK/mnt"
+# Same excludes as the old bootstrap extraction: .dockerenv is Docker's own
+# marker file, and /dev is devtmpfs at boot, populated by the kernel — a
+# tarred copy of the build container's /dev would just be dead weight.
+#
+# Root, deliberately: the rootfs's own files are owned by root (that is
+# correct — it is the guest's root filesystem), and only root can write
+# root-owned files onto the loop-mounted ext4.
+sudo tar -xf "$WORK/rootfs.tar" -C "$WORK/mnt" --exclude='.dockerenv' --exclude='dev/*'
+sudo umount "$WORK/mnt"
+
+# The image *file* itself was created by `truncate` above as the invoking
+# user and never needs to change hands — mkfs/mount/umount touch its
+# contents, not its ownership. Asserted, not assumed, since a stray `sudo`
+# reordering above would silently hand root ownership of a file the rest of
+# this pipeline expects to read and delete without sudo.
+[[ "$(stat -c '%U' "$OUT")" == "$(id -un)" ]] || {
+    echo "warning: ${OUT} is not owned by $(id -un) — sudo chown $(id -un) ${OUT}" >&2
+}
+echo "Wrote ${OUT}"