kojo

kojo

日本語

Remotely operate AI coding CLIs (Claude Code, Codex, Gemini CLI) on macOS from your mobile device.

┌─────────────────┐        Tailscale        ┌──────────────────┐
│  macOS Machine   │◄──────(P2P encrypted)──────►│  Mobile Browser  │
│                  │                         │                  │
│  kojo server     │   WebSocket / HTTP      │  Web UI          │
│  ├─ PTY: claude  │◄──────────────────────►│  ├─ xterm.js     │
│  ├─ PTY: codex   │                         │  ├─ React        │
│  └─ PTY: gemini  │                         │  └─ Web Push     │
└─────────────────┘                         └──────────────────┘

Features

• Single binary — Built with Go, web UI embedded
• tmux-backed sessions — CLI tools run inside tmux for crash resilience and persistence across kojo restarts
• Unified PTY — All CLIs handled uniformly via PTY. No SDK dependencies
• Tailscale P2P — No central server or database. Encrypted with WireGuard
• Zero config — Just run kojo with Tailscale running

Requirements

• macOS
• Go 1.25+
• Node.js 20+
• tmux
• Tailscale
• Supported CLIs: claude, codex, gemini (at least one)

Build

# Production build
make build

# Development (two terminals)
make dev-server   # Go server (--dev mode, proxies to Vite)
make dev-web      # Vite dev server

# Hot reload (auto rebuild on Go file changes)
make watch

Usage

# Via Tailscale (default, auto HTTPS)
kojo

# Local only
kojo --local

# Custom port (auto-increments if busy)
kojo --port 9090

By default, kojo listens on the Tailscale network via tsnet with HTTPS. Use --local or --dev to bind to localhost only.

Tailscale HTTPS Setup

kojo uses tsnet to join your Tailscale network directly as a node named kojo. All traffic is encrypted with WireGuard — no ports to open, no certificates to manage.

Prerequisites

1. Install Tailscale on your macOS machine and your mobile device
2. Sign in to the same Tailscale account on both devices
3. Ensure both devices appear in Tailscale admin console

How it works

When you run kojo (without --local):

1. kojo starts an embedded Tailscale node via tsnet
2. The node registers itself as kojo on your tailnet
3. HTTPS is automatically provisioned using Tailscale's built-in Let's Encrypt integration
4. Your server becomes reachable at https://kojo.<tailnet-name>.ts.net

$ kojo

  kojo v0.4.2 running at:

    https://kojo.tail1234.ts.net
    https://100.x.y.z:8080

First run

On the first launch, tsnet will print an authentication URL to stderr. Open it in your browser to authorize the node. This is a one-time step — credentials are cached in ~/.config/tsnet-kojo/.

Access from mobile

1. Install the Tailscale app on your phone
2. Sign in with the same account
3. Open https://kojo.<tailnet-name>.ts.net in your mobile browser

All communication is peer-to-peer via WireGuard. No data passes through a central server.

Security model

ACL (optional)

You can restrict which devices can access kojo using Tailscale ACLs:

{
  "acls": [
    {
      "action": "accept",
      "src": ["tag:mobile"],
      "dst": ["tag:kojo:*"]
    }
  ],
  "tagOwners": {
    "tag:mobile": ["autogroup:admin"],
    "tag:kojo":   ["autogroup:admin"]
  }
}

Troubleshooting

What it does

• Manage multiple sessions simultaneously (newest first)
• Session persistence via tmux (~/.config/kojo/sessions.json, auto-cleanup after 7 days). Sessions survive kojo restarts and crashes
• Session restart with tool-specific resume (claude --resume, codex resume, gemini --resume)
• Real-time PTY output streaming (xterm.js)
• Text input (Enter for newline, Shift+Enter to send) and special keys (Esc, Tab, Ctrl, arrows)
• Working directory path completion
• File browser (syntax highlighting for text, image preview)
• File attachment (camera, images, text)
• Git panel (status, log, diff, command execution)
• Web Push notifications (permission prompts, completion alerts)
• Yolo mode (auto-approve permissions)

Tech Stack

Install

go install github.com/loppo-llc/kojo/cmd/kojo@latest

License

MIT