docker-claude/README.md

# docker-claude

Runs [Claude Code](https://claude.ai/code) inside an isolated Docker environment with a proxy sidecar for controlled egress. Claude cannot reach the host filesystem or network directly.

## Architecture

```
┌──────────────────────────────────────────────────────────┐
│  Host machine                                            │
│                                                          │
│  claude.sh (control script)                              │
│       │                                                  │
│       ▼                                                  │
│  ┌──────────────────────────────────────────────────┐   │
│  │  Docker: claude-secure                           │   │
│  │                                                  │   │
│  │  ┌─────────────┐                                 │   │
│  │  │  claude     │──┐  claude-internal             │   │
│  │  │  (UID 1000) │  │  (internal: true)            │   │
│  │  └─────────────┘  ├──────────────► ┌──────────┐ │   │
│  │  ┌─────────────┐  │                │  proxy   │ │   │
│  │  │  webui      │──┘                │ (UID 13) │ │   │
│  │  │  (UID 1000) │                   └────┬─────┘ │   │
│  │  │  port 7681  │              proxy-external     │   │
│  │  └─────────────┘                        │        │   │
│  └──────────────────────────────────────────────────┘   │
│                                            │             │
│                                            ▼             │
│                                 internet (allowlisted)   │
└──────────────────────────────────────────────────────────┘
```

- **`claude`** — Claude Code CLI, UID 1000, on `claude-internal` only
- **`webui`** — Claude Code in a browser terminal (ttyd), UID 1000, on `claude-internal` only, port 7681
- **`proxy`** — Squid forward proxy, UID 13, bridges `claude-internal` ↔ internet with egress allowlist
- **`claude-internal`** — `internal: true`; no default gateway, containers cannot reach the internet directly
- **`proxy-external`** — Standard bridge; proxy sidecar only

## Prerequisites

- Docker Engine 24+
- Docker Compose v2 plugin (`docker compose version`)

## Setup

```bash
# 1. Clone / copy this repo
git clone <repo> docker-claude && cd docker-claude

# 2. Configure credentials
cp .env.example .env
$EDITOR .env   # set ANTHROPIC_API_KEY (and WEBUI_PASSWORD if using web mode)

# 3. Make the control script executable
chmod +x claude.sh
```

## Usage

### CLI mode

```bash
# Build images, start proxy, launch Claude Code interactively
./claude.sh start

# Start proxy if needed, launch Claude Code (faster on subsequent runs)
./claude.sh run

# Mount a host directory as the workspace
WORKSPACE_DIR=$HOME/myproject ./claude.sh run
```

### Web interface

Serves Claude Code as a browser terminal via [ttyd](https://github.com/tsl0922/ttyd), protected by HTTP basic auth.

```bash
# Add to .env first:
# WEBUI_PASSWORD=your-strong-password
# WEBUI_USER=claude   # optional, defaults to "claude"

./claude.sh web
# → Web interface running at http://0.0.0.0:7681

# To reach it from outside the sandbox host:
sbx ports <sandbox-name> --publish 7681:7681/tcp

# Stop web interface (keeps proxy running)
./claude.sh web-stop
```

### Other commands

```bash
./claude.sh stop          # Stop and remove all containers
./claude.sh update        # Rebuild images without cache
./claude.sh logs          # Tail proxy logs
./claude.sh logs webui    # Tail web interface logs
./claude.sh status        # Show container status
./claude.sh shell         # Debug bash shell in the Claude container
```

### Workspace

| Mode | Default | Override |
|---|---|---|
| CLI (`run`/`start`) | Named Docker volume (isolated) | `WORKSPACE_DIR=/path ./claude.sh run` |
| Web (`web`) | Named Docker volume (`claude-web-workspace`) | Edit `docker-compose.yml` volumes |

## Egress allowlist

Edit `proxy/squid.conf` and add domains to the `allowed_sites` ACL:

```
acl allowed_sites dstdomain api.anthropic.com
acl allowed_sites dstdomain statsig.anthropic.com
# acl allowed_sites dstdomain api.github.com
# acl allowed_sites dstdomain registry.npmjs.org
```

Rebuild after changes:

```bash
./claude.sh update
./claude.sh stop && ./claude.sh start
```

## Security controls

| Control | claude / webui | proxy |
|---|---|---|
| Non-root user | UID 1000 (`claude`) | UID 13 (`proxy`) |
| `no-new-privileges` | yes | yes |
| All capabilities dropped | yes | yes |
| Direct internet access | no (`internal` network only) | allowlisted only |
| Host filesystem | no mounts by default | none |
| Docker socket | not mounted | not mounted |
| Web auth | basic auth (ttyd `--credential`) | n/a |