Codync

The open-source, 1:1 alternative to Grok Bot and Muse.

Your coding agents, as teammates you can message.

Codync turns the coding agents on your computer — Claude Code, Codex, Cursor, Pi, OpenCode, Grok Build, Gemini, Copilot and ~40 more — into persistent bots you delegate to from your iPhone, Mac, Linux desktop or any terminal, the way you'd message a colleague. Pick who, say what, put the phone away. You get a notification when a bot finishes or needs your approval.

Why bots? On a phone, "find the right working session, then pick an environment" is too slow. With bots you already know who to hand the intent to: open the chat, type, done.

Why Codync

• Free and open source. No subscription, no paid tier, MIT licensed. It runs on your computer with the agents and accounts you already have.
• A 1:1 Grok Bot / Muse alternative. Persistent named bots, group chats, reply threads, bots asking each other for help, approval cards, per-bot memory, remote screen, voice calls and "needs you / done" notifications — the same features, without being tied to one model or one subscription.
• Any coding agent. Claude Code, Codex, Cursor, Gemini, Copilot, OpenCode, Pi, Grok Build and everything else in the ACP registry. Each bot picks its own.
• Rust core. codync-host is one small Rust binary for macOS and Linux that drives every agent, keeps the transcripts and serves every client.
• Native on every platform. SwiftUI on iPhone and Mac, GTK 4 / libadwaita on Linux, and a terminal UI for SSH. No web views, no Electron.
• Remote screen. See and control your computer from the iPhone over WebRTC (hardware H.264), and let bots use the screen themselves through the built-in computer tool.
• Voice calls. Talk to a bot hands-free from the iPhone and hear its replies read aloud.
• Private by default. Phones reach the host over an end-to-end encrypted channel (direct LAN/Tailscale or the Cloudflare relay); push notifications are sealed so the relay never sees their content.

Platforms

The host (codync-host, Rust) runs on macOS and Linux; every client talks to it, so all your bots and chats are the same everywhere.

How it works

Remote Apple client ⇄ encrypted channel (direct or Cloudflare cloud/) ⇄ codync-host ⇄ ACP agent
Local / SSH client  ⇄ loopback HTTP + SSE                             ⇄ codync-host
Host notifications → APNs worker (relay/) → iPhone

• Bots have a name, a character avatar, standing instructions, an agent backend, a project folder and a permission policy. Each bot has a persistent main chat and optional reply threads; the agent sessions underneath are an implementation detail (resumed with session/load, restarted with New session).
• Bots can ask each other for help. Tell one “ask Reviewer to check these changes.” The built-in team MCP server lets it discover your other visible bots and wait for a reply. Requests appear in both chats; each recipient keeps its own agent, folder and approvals. Native subagents stay under the coding agent's control. See bot collaboration.
• The chat only shows what matters: your messages, each turn's final reply, approval cards and notices. Every tool call, diff, plan and thought is one tap away in Full conversation. While a bot works, its row shows what it's doing right now.
• Agents are detected automatically: the host hydrates PATH from your login shell (plus Homebrew, ~/.local/bin, nvm, bun, volta, asdf, mise, pnpm…), finds every harness you have installed, and prefers its native ACP mode. Anything else in the official ACP registry can be picked too — Codync fetches it on first use (npx, uvx or a checksummed binary).
• codync-host (Rust, macOS + Linux) runs on your computer. It speaks the Agent Client Protocol to each agent, keeps transcripts in SQLite, and serves the phone. Every change carries a global rev, so the phone reconnects with since: rev and never misses anything.
• Usage limits come from your local installs, with no extra login: Claude via claude -p /usage (a local command, no model call) plus Claude Code's status line, Codex via ~/.codex/sessions. The phone, widgets and menu bar only see percentages.
• Push goes through a tiny relay that holds the APNs key. The phone trades its device token for an encrypted ticket; the host only ever holds tickets.

UI patterns (roster, character avatars, approval cards, trace sheet, "needs you / done" notifications) follow Grok Bot.

Install

Mac — download codync-macos.dmg and drag it to Applications, or:

brew install --cask leepokai/codync/codync

Both install the same signed, notarized app; the host ships inside it.

Open Codync in the menu bar → Install host. Open Codync opens the full window; Pair iPhone… shows the QR code.

Linux — native GTK 4 / libadwaita app plus the host:

brew install leepokai/codync/codync-host   # or a release tarball
codync-host install                        # systemd --user service
codync                                     # the desktop app (or codync-linux-x86_64.tar.gz / -arm64 from Releases)
codync-host pair                           # QR code in the terminal, or Settings in the app

Building the Linux app yourself needs libgtk-4-dev libadwaita-1-dev: cargo install --path apps/linux.

Linux server / cloud VM — the host runs headless on any distro (static binary, x86_64 + arm64). Setup, remote access and limitations: docs/guides/linux-servers.md.

Remote access uses an encrypted channel over direct LAN/Tailscale or the Cloudflare relay. Tailscale is optional. Configure matching app/host environments and follow the Cloudflare test guide; development configuration exists, while production configuration still needs completion.

Agents — install and sign in to whichever you use; Codync finds them. Claude Code, Codex and Pi run through their ACP adapters (fetched by npx, so Node.js is needed for those).

codync-host install also routes Claude Code's status line through codync-host statusline so live limits reach the host; an existing status line keeps working (it's wrapped, and restored on uninstall).

codync-host

Data lives in ~/.codync. The local bearer token authorizes loopback helpers and SSH-forwarded callers. Remote devices use individual keys and grants over the encrypted channel; revoke a lost device through device management rather than rotating the loopback token. Host methods and caller permissions live in host/src/api/mod.rs.

Repository

Build, install, restart and full checks: development guide.

The Xcode project is generated: xcodegen generate.

cd host && cargo test            # host
cd kit && swift test             # shared Swift
cd apps/linux && cargo test      # Linux app (needs GTK dev packages)
cd cloud && npm test            # cloud API / channel relay
cd relay && npm test             # relay tickets

Versioning

The major version is the phone ↔ host protocol: apps work with hosts of the same major version.

License

MIT