sbclaude

sbclaude runs Claude Code inside a throwaway Docker container with the bash sandbox and permission prompts disabled, against a configurable set of host bind mounts. The container stores nothing of its own (--rm); everything lives on the host. You only ever invoke sbclaude — it manages its own image and containers via the Docker SDK.

There is a single image, sbclaude, built on demand. It bundles everyday coding tools (Debian slim + git, ripgrep, Node 24/Yarn, a C toolchain, gh, glab, uv, jq), formatters and linters kept at their latest upstream release (clang-format, jsonnet, jsonnetfmt, shellcheck), Qt 6 development (qt6-base-dev plus ninja), webshot (a GPU Chrome driver for screenshots and visual diffs, with Chromium baked in), and a mobile reverse-engineering toolchain (a JDK, frida, mitmproxy, dex2jar, baksmali/smali, and launchers for the host-mounted Ghidra, Android SDK, jadx, and apktool).

How it works

The claude executable is not installed in the image. It is a self-contained native binary (Node is bundled in), so the host copy is bind-mounted read-only at run time — the image always tracks whatever version the host has. (Only glibc ≥ 2.17 is needed, which is why the base is Debian, not Alpine/musl.)
Your identity is mirrored: UID/GID/USER/HOME are passed in and an entrypoint recreates that user inside the container. This means:
- mounted ~/.claude files (incl. the 0600 .credentials.json) are owned correctly;
- paths resolve identically — a host path you paste into a prompt (/home/you/dev/foo) is bind-mounted at that same absolute path inside the box.
--dangerously-skip-permissions is passed (hence the non-root user — that flag refuses root), and a patched copy of your settings.json is mounted over the in-container one with sandbox.enabled=false, skipDangerousModePermissionPrompt=true (no bypass dialog) and tui="fullscreen". Your real settings file is never modified.
The image auto-builds on first use and rebuilds automatically when the packaged Dockerfile/entrypoint change (tracked via a content-hash label).

Install

uv tool install .         # or: pipx install .
# the image builds itself on first `sbclaude run`; or pre-build:
sbclaude build

Usage

sbclaude                          # run claude; cwd is the project (writable)
sbclaude run -p ~/dev/foo         # explicit project dir (writable, becomes workdir)
sbclaude run -r /data -w ~/scratch   # extra read-only / read-write mounts
sbclaude run --re --x11           # Ghidra/Android mounts + GUI passthrough
sbclaude run -- --version         # everything after -- goes to claude
sbclaude ls                       # list running sbclaude containers
sbclaude stop [--all]             # stop this project's boxes (or all with --all)
sbclaude shell                    # root debug shell in this project's box
sbclaude build [--no-cache]       # (re)build the image
sbclaude delete-image             # remove the sbclaude image
sbclaude config                   # show the config file path
sbclaude scaffold-noclip [DIR]    # write a noclip visual-regression harness into a project

`webshot`

Inside the box, webshot drives a real GPU-accelerated Chromium (baked into the image, so no project needs its own browser download), screenshots it, and compares the result against a baseline. It is deliberately generic: it knows about browsers, waiting, settling, screenshots, and image comparison, and nothing about any particular application — per-project knowledge is supplied with --wait-fn/--eval.

webshot doctor                                          # report the renderer actually in use
webshot shot http://localhost:3000 --out out.png --wait '#app'
webshot check http://localhost:3000 --baseline base.png
webshot compare a.png b.png --diff d.png

Exit codes: 0 ok, 1 regression, 2 software renderer (i.e. the GPU is not really being used), 3 missing baseline, 64 usage. Pair it with --gpu, and with --wayland when a headed window is wanted.

`scaffold-noclip`

Writes the project-side glue for a visual-regression workflow built on the webshot tool that ships in the image, into DIR (default: the current directory):

viewer-tests/nc.mjs        runner -- talks only to the app's own API, copied verbatim per project
viewer-tests/views.json    the only file you edit: which scene, and where the camera goes
viewer-tests/baselines/    approved output; effectively source, nothing can regenerate it
viewer-tests/out/          captures and diffs, rewritten every run
NEW_GAME.md                getting-started guide, including the non-obvious failure modes

sbclaude scaffold-noclip --scene MyGame/Level1   # substitute the scene id while writing
sbclaude scaffold-noclip ~/dev/foo --force       # overwrite existing files

Existing files are never overwritten without --force: an edited views.json or a blessed baseline is judgement that cannot be regenerated.

You can run several boxes against the same project directory at once. Each run gets a unique container name — the project name plus a short random suffix — so there is no name collision; override it with -n. sbclaude ls lists them all, sbclaude stop stops every box for the current project, and sbclaude shell attaches to it (or asks you to pass -n NAME when more than one is running).

`run` flags

Flag	Effect
`--re`	enable `--ghidra` + `--android` together
`--ghidra`	mount host Ghidra (`/usr/share/ghidra`) read-only
`--android`	mount Android SDK + `~/.android` + `/dev/kvm` (adb/emulator)
`--usb`	expose `/dev/bus/usb` for adb over USB
`--ios`	mount the host `usbmuxd` socket so frida reaches an iOS device over USB
`--gpu`	expose the host GPUs (NVIDIA runtime plus the DRM render nodes)
`--wayland`	forward the Wayland socket for GUI apps (preferred over `--x11`)
`--x11`	forward `DISPLAY` + `XAUTHORITY` for GUI apps (Ghidra GUI, jadx-gui, emulator)
`--ssh`	mount the host `~/.ssh` read-only and forward the ssh-agent, for SSH git remotes
`--gpg`	mount the host GnuPG home + agent socket for signing commits
`--session-recover`	install `cc-session-recover` (auto-resume) into the project on start
`--net bridge`	isolate the box’s network (default is `host` — `localhost` = your host)
`-r/-w/-p/-n/-i`	extra ro/rw mount, project, container name, image override

Configuration

All options live under a [tool.sbclaude] table. They are read from the global file at ~/.config/sbclaude/config.toml (path from platformdirs) and, for run, overlaid with the target project’s pyproject.toml [tool.sbclaude] table — project values win, so a repo can pin its own defaults. All keys optional:

[tool.sbclaude]
gpg = true       # mount the GnuPG home + agent for signing
network = "host" # default; "bridge" to isolate the box's network
re = true        # enable the Ghidra + Android mounts together
ssh = true       # mount ~/.ssh read-only + forward the ssh-agent for SSH git remotes
wayland = true   # forward the Wayland socket for GUI apps
x11 = true       # forward X11 for GUI apps
# image = "custom:latest"         # force a different image
# debian_mirror = "http://ftp.us.debian.org/debian" # apt mirror for image builds
# memory = "8g"                   # override the auto host-RAM cap ("0" disables)
# cpus = "4"                      # cap CPUs (uncapped by default)
# recover = true                  # install cc-session-recover into every project (off by default)
pass_env = ["AWS_REGION"]                          # forward host vars (AWS_PROFILE is default)
ro = ["~/dev*", "~/ghidra_scripts", "~/Downloads"] # read-only mounts (globs + ~ ok)
rw = []                                            # the project dir is always rw automatically

[tool.sbclaude.env] # inject fixed vars (e.g. Amazon Bedrock)
CLAUDE_CODE_USE_BEDROCK = "1"

The toggle keys re, ghidra, android, gpu, usb, ios, wayland, x11, ssh, and gpg mirror the matching run flags and default to false; setting one is the same as always passing that flag.

Debian mirror — when deb.debian.org is slow, point image builds at a faster archive mirror with debian_mirror (or --debian-mirror on build/run). Only the image’s main archive URI is rewritten; debian-security keeps pointing at deb.debian.org.

ro/rw accept globs (~/dev* → every matching dir) and ~; non-matching or missing paths are dropped. Every path is mounted at its real absolute path, so a host path you paste into a prompt resolves inside the box. The project (cwd or -p) is always read-write and overlays any read-only parent (e.g. ~/dev ro + ~/dev/proj rw → proj is writable).

Environment variables — inject with the [tool.sbclaude.env] table, forward host values by name with pass_env, or per-run with -e KEY=VALUE (precedence: managed defaults < [tool.sbclaude.env] < pass_env < -e). AWS_PROFILE is forwarded by default. This is how you point the box at a different backend such as Amazon Bedrock (CLAUDE_CODE_USE_BEDROCK=1 + your AWS_* vars; mount ~/.aws via ro if you use profiles).

uv project environment — by default the box sets UV_PROJECT_ENVIRONMENT to a container-local path (/tmp/sbclaude-uv-<project>), so uv sync/uv run build the virtualenv there instead of writing .venv into your bind-mounted project. A host-built .venv hard-codes the host interpreter path and would not resolve in the box anyway; the container is throwaway, so the redirected env is rebuilt per run. Override it by setting your own UV_PROJECT_ENVIRONMENT (via [env] or -e), or disable the behaviour entirely with manage_uv_env = false. There is no clean equivalent for Node — node_modules is fixed to the package root by Node’s resolver (only Yarn Berry’s YARN_NODE_LINKER=pnp removes it, at the cost of changing module resolution), and node_modules built on the box’s Linux is usually reusable on a Linux host anyway, so it is left untouched.

Alternate config dir — if CLAUDE_CONFIG_DIR is set on the host, sbclaude mounts that directory (its .claude.json, settings.json, history) and points claude at it inside the box instead of ~/.claude.

Session recovery

cc-session-recover lets Claude Code pick a long-running task back up after a quota or rate-limit pause. It is off by default — enable it per run with --session-recover, or for every run with recover = true in the config. When enabled, the container entrypoint runs the tool’s install-into-project.sh against the project before launching claude, which sets up its SessionStart and Stop hooks and a HANDOFF.md.

The tool is vendored into the image as a git clone (not the npm package) at /opt/cc-session-recover, with PR #2 (safer watcher argument handling and the opt-in CC_REMIND_MODE prompt-injection limit) applied on top. Two further patches keep the installer tidy: it no longer copies settings.example.json into the project, and its own .gitignore handling is disabled. The installer writes into the project’s .claude/ (hooks and settings.local.json, merged with jq) and a HANDOFF.md; because the project is bind-mounted read-write, those files land in your real repository and persist, which is why this is opt-in. Afterwards the entrypoint appends the recovery artifacts (HANDOFF.md, auto-continue.md, session-recover.js, session-recover.yaml, standing-instructions.md, statusline-quota-cache.sh, and the three hook scripts) to the project’s .gitignore, each only when absent. If the install fails, the box aborts rather than starting a session that silently lacks recovery.

MCP servers

MCP server configs live in your mounted ~/.claude.json, so they carry into the box — but the server command must be runnable inside the container. A host Python venv won’t work: its bin/python symlinks to a host-only interpreter (e.g. /usr/bin/python3.13), which doesn’t exist in the box → ENOENT. The image ships Python 3 in a virtualenv at /opt/venv (with the mcp SDK and pre-commit pre-installed) and uv, so point the command at one of:

uv run /abs/path/to/server.py — best: reads the script’s PEP 723 deps, works on the host too. Example: claude mcp add ghidra -- uv run ~/dev/ghidra-mcp/bridge_mcp_ghidra.py.
/opt/venv/bin/python3 /abs/path/to/server.py — the container’s venv Python (has mcp pre-installed); container-only. /opt/venv/bin is first on PATH, so a bare python3 resolves here too.

A server that talks to a process on the host (e.g. a Ghidra GUI on localhost) works out of the box because the box defaults to host networking; pass --net bridge only if you want to isolate it.

Git over SSH and commit signing

Pushing over SSH and signing commits need the host’s private keys, which are not mounted by default (the box is a fully-autonomous, no-prompt agent — see Hardening). Opt in per run, or globally with ssh = true and gpg = true under [tool.sbclaude]:

--ssh bind-mounts ~/.ssh read-only, so SSH remotes authenticate with the host’s keys and known_hosts. Read-only means newly-learnt host keys are not written back. It also forwards the host’s ssh-agent: $SSH_AUTH_SOCK is bind-mounted at its own path and set in the box, so keys that are passphrase-protected or held in a hardware token still work — the host agent does the signing and the secret never enters the container. Without this a box holding only encrypted key files would stall on a passphrase prompt nothing can answer. Symlinks inside ~/.ssh are followed too: a config (or key) linked into a dotfiles repository has its target mounted read-only at the same path, so the link does not dangle and every Host alias keeps working.
--gpg bind-mounts the host GnuPG home (read-write — gpg needs to write lock files and the trustdb) and overlays the host’s live gpg-agent socket at ~/.gnupg/S.gpg-agent. The host agent performs the signing and owns the secret keys, so a cached passphrase carries over and any pinentry prompt appears on the host. The image ships gnupg and openssh-client; your mounted ~/.gitconfig (with user.signingkey/commit.gpgsign) does the rest.

sbclaude run --ssh --gpg -p ~/dev/foo   # inside: git push, git commit -S both work

Your ~/.gitconfig is always mounted read-only, along with every file it pulls in via an [include] path = ... directive (resolved with git config --includes), so a split config carries into the box intact.

RE toolchain (`--re`)

Mounted from the host (your exact versions): Ghidra (analyzeHeadless, ghidraRun), Android SDK (adb, emulator, sdkmanager, avdmanager), jadx, apktool, plus ~/.android (adb keys + AVDs) and /dev/kvm for emulator acceleration.

Installed in the image: Temurin JDK 21 (Ghidra 12 needs it), build-essential + binutils, frida + frida-tools (pinned to the host version), mitmproxy, dex2jar, baksmali/smali, CLI audio tools (ffmpeg, sox, flac, vorbis-tools, opus-tools, lame, mpg123, wavpack, shntool, plus vgmstream-cli for game audio), CLI image tools (ImageMagick, zbar, deark, pngdefry for -iphone PNGs), czkawka-cli (duplicate/similar finder), and the X11/GL/audio libs the mounted GUI binaries need.

sbclaude run --re --x11 -p ~/dev/some-apk-re
#   inside: jadx -d work/jadx-out base/classes*.dex
#           apktool d base -o work/axml-decoded
#           analyzeHeadless ~/dev/x-re proj -import lib/arm64-v8a/foo.so
#           adb devices ; emulator -avd ford-x86_64-api35 -writable-system &
#           frida -U -f com.x.y -l hook.js

--x11 mounts /tmp/.X11-unix + your session xauth cookie and sets DISPLAY/ XAUTHORITY. Java/Swing (Ghidra) renders through XWayland (:0). If a GUI fails with a cookie error, run on the host: xhost +SI:localuser:$USER.

--wayland is the better option when the app speaks Wayland: it forwards the compositor socket alone, and a Wayland client cannot read other windows or inject input into them, whereas an X11 cookie grants exactly that over the whole session. The socket is re-homed under the box’s own /run/user/<uid> and WAYLAND_DISPLAY/XDG_RUNTIME_DIR are set to match.

--gpu uses the NVIDIA container runtime when it is present and also passes through the DRM render nodes (/dev/dri/renderD*), so Mesa on AMD/Intel and Vulkan/VA-API work too. The entrypoint re-adds the device groups Docker granted, and synthesises the glvnd/Vulkan/GBM manifests the NVIDIA toolkit does not install, so GL, EGL, and Vulkan clients get the real driver instead of a software fallback.

--ios targets an iOS device attached to the host. The host runs usbmuxd (it owns the USB device), and frida’s usbmux backend reaches the device through that daemon’s socket — so instead of claiming raw USB (which would clash with the host usbmuxd), --ios bind-mounts /var/run/usbmuxd plus the host’s /var/lib/lockdown pairing records. Combine with --re so frida is present:

sbclaude run --re --ios -p ~/dev/some-ios-re
#   inside: frida-ls-devices            # the host's device shows up over usbmux
#           frida -U -f com.x.y -l hook.js

The host needs usbmuxd running and the device already paired (trusted). If frida sees no device, confirm idevice_id -l works on the host first.

Hardening

This deliberately removes Claude’s own sandbox and permission prompts, so the box leans on Docker for confinement instead. Every run is hardened by default (defense-in-depth — it limits blast radius, it is not a guarantee):

Build time: minimal Debian slim, --no-install-recommends + cleaned apt lists, no secrets baked in (the claude binary and all auth are bind-mounted), OCI provenance labels, and all setuid/setgid bits stripped from the image.
Run time: --security-opt no-new-privileges, --cap-drop ALL plus only the six caps the root entrypoint needs to create the mapped user, drop to it via gosu, and let tini (PID 1) forward signals such as SIGWINCH to the non-root child (CHOWN, DAC_OVERRIDE, FOWNER, KILL, SETUID, SETGID), a --pids-limit, a non-root mapped user, and the default seccomp/AppArmor profiles (never disabled). The claude process itself ends up with an empty effective capability set.
Can’t lock the host: --pids-limit stops fork bombs, and --memory with an equal --memory-swap bounds RAM with no extra swap, so a runaway box is OOM-killed instead of thrashing the host into a freeze. The default cap is derived from host RAM (reserving the larger of 2 GiB or an eighth for the host); set memory to override or "0" to disable, and cpus to cap CPU (uncapped by default — saturation slows but does not lock). These are enforced by cgroups, i.e. the systemd cgroup driver on a systemd host — a separate systemd-run wrapper is unnecessary (and would not bound the container, which runs under the Docker daemon’s cgroup, not the CLI’s).

Disable per run with --no-harden, globally with harden = false in config (this also drops the resource caps), and add your own Docker flags (e.g. --read-only) via docker_args = [...].

Still: the containerized Claude can run any command and read/write every mounted path without asking, with unrestricted network. Keep writable mounts minimal (the config defaults to read-only for everything but the project) and don’t mount secrets you don’t want a fully-autonomous agent to touch. This is why --ssh and --gpg are opt-in: they expose your private SSH and GPG key material (the GnuPG home read-write) to that agent. Forwarding an agent socket does not hand over the secret itself, but it does let the box ask the host agent to sign with any key it holds, for as long as the box runs.