PI Docker Sandbox

A sandboxed Docker environment for the PI coding agent.

Features

• Filesystem isolation — PI can only access explicitly mounted directories
• Minimal toolset — git, jq, node, npm, ripgrep, and octave preinstalled
• Non-root execution — runs as unprivileged pi user
• Security hardening — dropped capabilities, no-new-privileges, read-only rootfs
• OAuth login support — use your Anthropic/GitHub/Google subscription
• Local LLM support — connect to Ollama/LM Studio on the host
• Host tool mounting — expose simple host binaries (python, ghdl, emacs, …) to the container via --tools
• Unrestricted mode — run with host-like access when you do not want Docker to be a sandbox
• Extension development — mount your extensions directory for seamless dev
• Arch-based base image — matches the glibc/ABI of an Arch host, so mounted host binaries load without version skew

Quick Start

1. Build the image

cd pi-sandbox
docker build -t pi-sandbox .

2. First-time OAuth login

./pi-docker --login
# Inside PI, run /login and select your provider
# Open the displayed URL in your host browser
# After login completes, exit PI (ctrl+c twice)

3. Run PI in a project

cd ~/my-project
pi-docker

Usage

pi-docker                              # Run in current directory
pi-docker ~/extra-repo                 # Mount additional repo under /repos/extra-repo
pi-docker ~/repo1 ~/repo2              # Mount multiple extra directories
pi-docker --login                      # OAuth login mode
pi-docker --build                      # Rebuild image, then run
pi-docker --tools python,ghdl          # Mount individual host tools
pi-docker --tools emacs ~/extra-repo   # Combine with other options
pi-docker --host-apps                  # Full host application access (write jail)
pi-docker --host-apps --local          # Host apps + local LLMs
pi-docker --unrestricted               # Host-like access, no Docker sandboxing
pi-docker -- --provider anthropic      # Pass flags to PI after --

Setup

Prerequisites

• Docker installed and running
• ~/.pi/agent/ directory exists (created by previous PI installation)

Skills

Skills are mounted from a local directory (default ~/pi-skills). Set a custom path:

# Add to your .zshrc / .bashrc:
export PI_SKILLS_DIR=~/path/to/your/skills

On the host, ~/.pi/agent/skills is a symlink to the same repo. Inside the container, the directory is bind-mounted directly.

LifeOS package

When ~/.pi/agent/pi-lifeos.json exists, pi-docker automatically mounts the host-owned package, LifeOS runtime, skill library, and USER directory at their real absolute paths. They are read-only in the normal restricted sandbox; LifeOS adapter state remains writable under the mounted Pi config directory.

Install/configure it from the host repository once:

~/Documents/10-repos/11-gitRepo/pi-lifeos/scripts/install.sh --auto
pi-docker
# Inside Pi: /lifeos doctor

Use --local if Pulse on host port 31337 must be reachable. Unrestricted mode also works but is no longer required merely to load LifeOS.

Extensions

Set the extensions directory (default is ~/pi-extensions):

# Add to your .zshrc / .bashrc:
export PI_EXTENSIONS_DIR=~/path/to/your/extensions

Host Tools

Mount host-installed tools into the container so the LLM can run them (e.g. to test code):

pi-docker --tools python,ghdl,octave

Each tool is auto-discovered via which, its shared-library dependencies are resolved via ldd, and sibling binaries / RPATH directories are pulled in automatically. Everything is mounted read-only into an isolated /opt/host-tools/ tree. The entrypoint generates wrapper scripts that invoke the host's dynamic linker with --library-path, and exports LD_LIBRARY_PATH so child processes launched by exec (common in multi-binary tools like Octave) also find the right libs.

How it works:

• Tool binary → /opt/host-tools/real/<name> (read-only), wrapped by a script in /opt/host-tools/bin/<name> that's put on PATH.
• Sibling binaries (same directory, shared prefix — e.g. octave-cli-11.1.0, octave-config-*) → bind-mounted at their literal host paths so hardcoded execve("/usr/bin/<sibling>") calls resolve.
• Non-glibc shared libs → /opt/host-tools/lib/<SONAME> (e.g. libfreetype.so.6), exposed to child processes via LD_LIBRARY_PATH. Glibc family (libc, libm, libpthread, …) is intentionally excluded from this dir to avoid mixing host/container glibc.
• Tool-specific lib subdirs (anything that isn't a system lib dir like /usr/lib) → bind-mounted at their literal paths so RPATH/RUNPATH lookups succeed. RPATH is also read directly via readelf when available.
• Runtime data (fonts, icons, locale files, Octave's .m scripts, Python stdlib, …) → the host's /usr/{bin,sbin,lib,lib32,lib64,libexec,share,include} are bind-mounted at /opt/host-tools/host-usr/* (read-only). XDG_DATA_DIRS and PATH in the wrapper point at these. /usr/local and /usr/src are not mounted, to avoid exposing user-installed scripts that may embed secrets.

Limitations:

• Tool names must match what which finds on the host.
• If a tool expects writable config under /usr/local or spawns an unrelated binary via absolute path (outside its own sibling prefix), you may need to add it to --tools explicitly.
• Binaries from a host with newer glibc than the container's will fail with GLIBC_x.xx not found. The default Arch base image matches an Arch host's glibc, but if your host runs something newer, rebuild the image (pi-docker --build) so the container picks up the latest archlinux:latest.

When not to use --tools:

For applications that carry their own runtime ecosystem — package managers, plugin systems, autoload scripts, version-coupled data files — mounting the host binary is fragile. Octave is the canonical example: its PKG_ADD bootstrap calls builtins that only resolve under the full installed environment, which the mount-and-wrap approach can't recreate.

For such apps, either install them directly in the container's Dockerfile (octave is preinstalled for this reason), or use --host-apps (see below) which exposes every host-installed app at once.

Rule of thumb:

• Standalone binaries (jq, ghdl, small Python CLIs): --tools is fine.
• Apps with their own package/plugin system: add to Dockerfile, or use --host-apps.

Host Apps Mode (--host-apps)

A looser sandbox that gives the container full read access to every host-installed application, while keeping writes confined. The sandbox becomes a write jail rather than a filesystem sandbox — similar to distrobox or Fedora's toolbox.

pi-docker --host-apps            # any host binary just works
pi-docker --host-apps --local    # + local LLMs

What it mounts (read-only, at literal paths, overlaying the container):

• /usr/bin, /usr/sbin, /usr/lib, /usr/lib32, /usr/lib64, /usr/libexec, /usr/share, /usr/include

Not mounted (kept container-local or excluded):

• /usr/local, /usr/src — may contain user-installed scripts with hardcoded secrets
• /etc, /opt, /var, /home/<you> — container has its own
• $HOME/.ssh, $HOME/.aws, etc. — never exposed unless you explicitly mount them as an extra path

What stays writable:

• /workspace, /home/pi/.pi/, /tmp (tmpfs)

What stays enforced (same as default mode):

• --cap-drop=ALL, --security-opt=no-new-privileges, --read-only rootfs
• Non-root pi user (UID 1000)
• Bridge network (or host network only with --local/--login)

Tradeoffs:

• + Every host app works out of the box: octave, ghdl, vivado, matlab (if in /usr), etc.
• + No --tools maintenance, no wrapper scripts, no library dance
• − The agent can read anything under host /usr. Most of /usr/share is package data, but still worth being aware of.
• − Writes are still blocked, but reads could go out via network (use with --local scoped to localhost services if you care).

Requires: host must have node somewhere on /usr/bin (the container's PI agent at /opt/pi-agent/bin/pi has a #!/usr/bin/env node shebang). Every Arch machine with nodejs installed satisfies this.

When to prefer --host-apps over --tools + Dockerfile installs:

• You have many host tools you'd otherwise have to enumerate in --tools
• You trust the agent's scope for the session and want frictionless access
• Tools depend on host-side config under /usr/share (fonts, themes, plugin packs)

When to prefer the default sandbox:

• You're running a task you don't fully trust
• You want the tightest possible read surface
• You're debugging and want reproducible, image-pinned tool versions

Unrestricted Mode (--unrestricted, --no-sandbox)

Use this when you want PI to behave as closely as possible to a host install, with Docker no longer acting as the security boundary:

pi-docker --unrestricted
pi-docker --no-sandbox                 # alias

What changes:

• Runs with --privileged
• Runs as your host UID/GID and supplementary groups
• Uses your host HOME, USER, and LOGNAME
• Uses host networking
• Disables --cap-drop=ALL, no-new-privileges, read-only rootfs, and tmpfs write jails
• Keeps PI extension npm packages in isolated Docker volumes at /pi-npm-global and /pi-npm-cache
• Exposes the bundled PI packages to extensions through NODE_PATH
• Mounts host /etc, /home, /media, /mnt, /root, /run, /srv, /tmp, /usr, and /var read-write at their normal paths
• Mounts host / read-write at /host
• Starts in the real host path for your current directory instead of /workspace

--unrestricted supersedes --tools and --host-apps.

Important: host /opt is available at /host/opt, not mounted over /opt, because the container's PI agent is installed under /opt/pi-agent. Mounting host /opt at /opt would hide the bundled PI executable before it can start.

Local LLMs (Ollama / LM Studio)

Use the --local flag to enable host networking so the container can reach local LLM servers. This is required because servers like LM Studio typically bind to 127.0.0.1 only, which is unreachable from Docker's default bridge network.

pi-docker --local                      # local LLMs only
pi-docker --local --tools python       # local LLMs + host tools

Configure ~/.pi/agent/models.json with localhost URLs as usual:

{
  "providers": {
    "ollama": {
      "baseUrl": "http://localhost:11434/v1",
      "api": "openai-completions",
      "apiKey": "ollama",
      "models": [
        { "id": "llama3.1:8b" }
      ]
    },
    "lm-studio": {
      "baseUrl": "http://localhost:1234/v1",
      "api": "openai-completions",
      "apiKey": "lm-studio",
      "models": [
        { "id": "your-model-name" }
      ]
    }
  }
}

Installation (symlink to PATH)

ln -s "$(pwd)/pi-docker" ~/.local/bin/pi-docker

Container Paths

Host Path	Container Path	Mode	Type
Current directory	/workspace	read-write	bind mount
~/.pi/agent/	/home/pi/.pi/agent/	read-write	bind mount
LifeOS package/runtime/skills/USER (from pi-lifeos.json)	same host absolute paths	read-only	bind mounts
Skills dir	/home/pi/.pi/agent/skills/	read-write	bind mount
Extensions dir	/home/pi/.pi/agent/extensions/	read-write	bind mount
Extra paths	/repos/<dirname>	read-write	bind mount
Extra paths — --unrestricted	same absolute path	read-write	bind mount
npm packages	/home/pi/.npm-global/	read-write	named volume
npm cache	/home/pi/.npm/	read-write	named volume
Host tools (binary) — --tools	/opt/host-tools/real/<name>	read-only	bind mount
Host tools (non-glibc libs) — --tools	/opt/host-tools/lib/	read-only	bind mount
Host tools (siblings, RPATH dirs) — --tools	original host path	read-only	bind mount
Host /usr/{bin,lib,…} — --tools	/opt/host-tools/host-usr/	read-only	bind mount
Host tools (wrappers) — --tools	/opt/host-tools/bin/	read-write	tmpfs
Host /usr/{bin,sbin,lib,lib32,lib64,libexec,share,include} — --host-apps	same path	read-only	bind mount
Host /etc, /home, /media, /mnt, /root, /run, /srv, /tmp, /usr, /var — --unrestricted	same path	read-write	bind mount
Host / — --unrestricted	/host	read-write	bind mount
npm packages — --unrestricted	/pi-npm-global/	read-write	named volume
npm cache — --unrestricted	/pi-npm-cache/	read-write	named volume
/tmp	/tmp	read-write	tmpfs
~/.cache	/home/pi/.cache/	read-write	tmpfs

Named volumes (pi-sandbox-npm-global, pi-sandbox-npm-cache) persist between runs so extensions only install once.

Updating PI

1. Edit Dockerfile — change the version number in the npm install -g @earendil-works/pi-coding-agent@… line
2. Rebuild: pi-docker --build or docker build -t pi-sandbox .
3. Clear cached extensions: docker volume rm pi-sandbox-npm-global pi-sandbox-npm-cache
4. First run after update will reinstall extensions into the volumes

Because the base image is archlinux:latest (rolling), a rebuild also refreshes the container's glibc and system libs. If a host binary starts failing with GLIBC_x.xx not found after a host system update, rerun pi-docker --build to resync.

Uninstalling Host PI

After verifying the container works:

npm uninstall -g @mariozechner/pi-coding-agent @earendil-works/pi-coding-agent
npm uninstall -g @aliou/pi-extension-dev @plannotator/pi-extension @tmustier/pi-skill-creator pi-planning-with-files pi-subagents

Keep ~/.pi/agent/auth.json and models.json — the container uses them.

Security

• Runs as non-root user (pi, UID 1000)
• All Linux capabilities dropped (--cap-drop=ALL)
• No privilege escalation (--security-opt=no-new-privileges)
• Read-only root filesystem (--read-only)
• tmpfs for /tmp (no persistent writes outside mounts)
• No --network host in normal mode (only in --login mode)