claude-instance

Claude DevContainer

A secure, AI-agent-ready development container base image for Claude Code and Gemini CLI.

Features

• Node.js 22 with pnpm
• Claude Code and Gemini CLI pre-installed
• Firewall with domain allowlisting (iptables/ipset)
• Security hooks to prevent common mistakes
• ZSH with Powerlevel10k theme
• tmux for persistent terminal sessions

Quick Start

Run this in your project root to initialize:

curl -fsSL https://raw.githubusercontent.com/zookanalytics/claude-devcontainer/main/scripts/init-project.sh | bash

This creates:

• .devcontainer/devcontainer.json - configured for the base image
• .devcontainer/allowed-domains.txt - template for project-specific domains
• .devcontainer/post-create-project.sh - template for project setup

Then open in VS Code and "Reopen in Container".

Manual Setup

Alternatively, add to your project's .devcontainer/devcontainer.json:

{
  "name": "${localEnv:PROJECT_NAME}-${localWorkspaceFolderBasename}",
  "image": "ghcr.io/zookanalytics/claude-devcontainer:latest",
  "runArgs": [
    "--cap-add=NET_ADMIN",
    "--cap-add=NET_RAW",
    "--cap-add=SYSLOG"
  ],
  "remoteUser": "node",
  "workspaceMount": "source=${localWorkspaceFolder},target=/workspace,type=bind,consistency=delegated",
  "workspaceFolder": "/workspace",
  "mounts": [
    "source=${localEnv:PROJECT_NAME}-node-modules-${localWorkspaceFolderBasename},target=/workspace/node_modules,type=volume",
    "source=${localEnv:PROJECT_NAME}-claude-config,target=/home/node/.claude,type=volume",
    "source=${localEnv:PROJECT_NAME}-gemini-config,target=/home/node/.gemini,type=volume",
    "source=pnpm-store,target=/workspace/.pnpm-store,type=volume"
  ],
  "postCreateCommand": "/usr/local/bin/post-create.sh"
}

Extending Domain Allowlist

The base image includes common domains (npm, GitHub, Anthropic, Google, etc.). Add project-specific domains in .devcontainer/allowed-domains.txt:

# Project-specific domains
api.your-service.com
your-backend.example.com

Project-Specific Setup

Create .devcontainer/post-create-project.sh for project-specific initialization:

#!/bin/bash
set -e

# Install project dependencies
pnpm install

# Install Playwright browsers
pnpm exec playwright install

# Any other project-specific setup
echo "Project setup complete!"

The base post-create.sh will automatically call this script if it exists.

Security Hooks

Both Claude Code and Gemini CLI are configured with security hooks that prevent:

• Pushing directly to main/master branches
• Using --no-verify to bypass pre-commit hooks
• Using --admin to bypass GitHub branch protection
• Leaking sensitive environment variables
• Accessing sensitive files (.env, credentials, keys)

Hooks are installed at:

• /etc/claude-code/hooks/ - Claude Code hooks
• /etc/gemini-code/hooks/ - Gemini CLI hooks (symlinks to Claude hooks)

Gemini CLI Setup

The base image includes Gemini CLI and security hooks. For project-level Gemini config, create .gemini/settings.json:

{
  "tools": {
    "enableHooks": true
  },
  "hooks": {
    "BeforeTool": [
      {
        "matcher": "run_shell_command",
        "hooks": [
          {
            "name": "prevent-main-push",
            "type": "command",
            "command": "/etc/gemini-code/hooks/prevent-main-push.sh",
            "timeout": 10000
          }
        ]
      }
    ]
  }
}

See /etc/gemini-code/settings.json for the full template.

Examples

See the examples/ directory for:

• devcontainer.json - Full consumer configuration template
• allowed-domains.txt - Example project-specific domain allowlist

License

MIT