cmux
cmux is a Ghostty-based macOS terminal with vertical tabs and notifications for AI coding agents.
Features
<table> <tr> <td width="40%" valign="middle"> <h3>Notification rings</h3> Panes get a blue ring and tabs light up when coding agents need your attention </td> <td width="60%"> <img src="./docs/assets/notification-rings.png" alt="Notification rings" width="100%" /> </td> </tr> <tr> <td width="40%" valign="middle"> <h3>Notification panel</h3> See all pending notifications in one place, jump to the most recent unread </td> <td width="60%"> <img src="./docs/assets/sidebar-notification-badge.png" alt="Sidebar notification badge" width="100%" /> </td> </tr> <tr> <td width="40%" valign="middle"> <h3>In-app browser</h3> Split a browser alongside your terminal with a scriptable API ported from <a href="https://github.com/vercel-labs/agent-browser">agent-browser</a> </td> <td width="60%"> <img src="./docs/assets/built-in-browser.png" alt="Built-in browser" width="100%" /> </td> </tr> <tr> <td width="40%" valign="middle"> <h3>Vertical + horizontal tabs</h3> Sidebar shows git branch, linked PR status/number, working directory, listening ports, and latest notification text. Split horizontally and vertically. </td> <td width="60%"> <img src="./docs/assets/vertical-horizontal-tabs-and-splits.png" alt="Vertical tabs and split panes" width="100%" /> </td> </tr> <tr> <td width="40%" valign="middle"> <h3>SSH</h3> <code>cmux ssh user@remote</code> creates a workspace for a remote machine. Browser panes route through the remote network so localhost just works. Drag an image into a remote session to upload via scp. </td> <td width="60%"> <img src="./docs/assets/ssh.png" alt="cmux SSH" width="100%" /> </td> </tr> <tr> <td width="40%" valign="middle"> <h3>Claude Code Teams</h3> <code>cmux claude-teams</code> runs Claude Code's teammate mode with one command. Teammates spawn as native splits with sidebar metadata and notifications. No tmux required. </td> <td width="60%"> <img src="./docs/assets/claude-code-teams.png" alt="Claude Code Teams" width="100%" /> </td> </tr> </table>- Browser import — Import cookies, history, and sessions from Chrome, Firefox, Arc, and 20+ browsers so browser panes start authenticated
- Custom commands — Define project-specific actions in
cmux.jsonthat launch from the command palette - Scriptable — CLI and socket API to create workspaces, split panes, send keystrokes, and automate the browser
- Native macOS app — Built with Swift and AppKit, not Electron. Fast startup, low memory.
- Ghostty compatible — Reads your existing
~/.config/ghostty/configfor themes, fonts, and colors - GPU-accelerated — Powered by libghostty for smooth rendering
Install
DMG (recommended)
<a href="https://github.com/manaflow-ai/cmux/releases/latest/download/cmux-macos.dmg"> <img src="./docs/assets/macos-badge.png" alt="Download cmux for macOS" width="180" /> </a>Open the .dmg and drag cmux to your Applications folder. cmux auto-updates via Sparkle, so you only need to download once.
Homebrew
brew tap manaflow-ai/cmux
brew install --cask cmux
To update later:
brew upgrade --cask cmux
On first launch, macOS may ask you to confirm opening an app from an identified developer. Click Open to proceed.
Why cmux?
I run a lot of Claude Code and Codex sessions in parallel. I was using Ghostty with a bunch of split panes, and relying on native macOS notifications to know when an agent needed me. But Claude Code's notification body is always just "Claude is waiting for your input" with no context, and with enough tabs open I couldn't even read the titles anymore.
I tried a few coding orchestrators but most of them were Electron/Tauri apps and the performance bugged me. I also just prefer the terminal since GUI orchestrators lock you into their workflow. So I built cmux as a native macOS app in Swift/AppKit. It uses libghostty for terminal rendering and reads your existing Ghostty config for themes, fonts, and colors.
The main additions are the sidebar and notification system. The sidebar has vertical tabs that show git branch, linked PR status/number, working directory, listening ports, and the latest notification text for each workspace. The notification system picks up terminal sequences (OSC 9/99/777) and has a CLI (cmux notify) you can wire into agent hooks for Claude Code, OpenCode, etc. When an agent is waiting, its pane gets a blue ring and the tab lights up in the sidebar, so I can tell which one needs me across splits and tabs. Cmd+Shift+U jumps to the most recent unread.
The in-app browser has a scriptable API ported from agent-browser. Agents can snapshot the accessibility tree, get element refs, click, fill forms, and evaluate JS. You can split a browser pane next to your terminal and have Claude Code interact with your dev server directly.
Everything is scriptable through the CLI and socket API — create workspaces/tabs, split panes, send keystrokes, open URLs in the browser.
The Zen of cmux
cmux is not prescriptive about how developers hold their tools. It's a terminal and browser with a CLI, and the rest is up to you.
cmux is a primitive, not a solution. It gives you a terminal, a browser, notifications, workspaces, splits, tabs, and a CLI to control all of it. cmux doesn't force you into an opinionated way to use coding agents. What you build with the primitives is yours.
The best developers have always built their own tools. Nobody has figured out the best way to work with agents yet, and the teams building closed products definitely haven't either. The developers closest to their own codebases will figure it out first.
Give a million developers composable primitives and they'll collectively find the most efficient workflows faster than any product team could design top-down.
Documentation
For more info on how to configure cmux, head over to our docs.
Keyboard Shortcuts
Workspaces
| Shortcut | Action |
|---|---|
| ⌘ N | New workspace |
| ⌘ 1–8 | Jump to workspace 1–8 |
| ⌘ 9 | Jump to last workspace |
| ⌃ ⌘ ] | Next workspace |
| ⌃ ⌘ [ | Previous workspace |
| ⌘ ⇧ W | Close workspace |
| ⌘ ⇧ R | Rename workspace |
| ⌘ B | Toggle sidebar |
Surfaces
| Shortcut | Action |
|---|---|
| ⌘ T | New surface |
| ⌘ ⇧ ] | Next surface |
| ⌘ ⇧ [ | Previous surface |
| ⌃ Tab | Next surface |
| ⌃ ⇧ Tab | Previous surface |
| ⌃ 1–8 | Jump to surface 1–8 |
| ⌃ 9 | Jump to last surface |
| ⌘ W | Close surface |
Split Panes
| Shortcut | Action |
|---|---|
| ⌘ D | Split right |
| ⌘ ⇧ D | Split down |
| ⌥ ⌘ ← → ↑ ↓ | Focus pane directionally |
| ⌘ ⇧ H | Flash focused panel |
Browser
Browser developer-tool shortcuts follow Safari defaults and are customizable in Settings → Keyboard Shortcuts.
| Shortcut | Action |
|---|---|
| ⌘ ⇧ L | Open browser in split |
| ⌘ L | Focus address bar |
| ⌘ [ | Back |
| ⌘ ] | Forward |
| ⌘ R | Reload page |
| ⌥ ⌘ I | Toggle Developer Tools (Safari default) |
| ⌥ ⌘ C | Show JavaScript Console (Safari default) |
Notifications
| Shortcut | Action |
|---|---|
| ⌘ I | Show notifications panel |
| ⌘ ⇧ U | Jump to latest unread |
Find
| Shortcut | Action |
|---|---|
| ⌘ F | Find |
| ⌘ G / ⌘ ⇧ G | Find next / previous |
| ⌘ ⇧ F | Hide find bar |
| ⌘ E | Use selection for find |
Terminal
| Shortcut | Action |
|---|---|
| ⌘ K | Clear scrollback |
| ⌘ C | Copy (with selection) |
| ⌘ V | Paste |
| ⌘ + / ⌘ - | Increase / decrease font size |
| ⌘ 0 | Reset font size |
Window
| Shortcut | Action |
|---|---|
| ⌘ ⇧ N | New window |
| ⌘ , | Settings |
| ⌘ ⇧ , | Reload configuration |
| ⌘ Q | Quit |
Nightly Builds
cmux NIGHTLY is a separate app with its own bundle ID, so it runs alongside the stable version. Built automatically from the latest main commit and auto-updates via its own Sparkle feed.
Report nightly bugs on GitHub Issues or in #nightly-bugs on Discord.
Session restore (current behavior)
On relaunch, cmux currently restores app layout and metadata only:
- Window/workspace/pane layout
- Working directories
- Terminal scrollback (best effort)
- Browser URL and navigation history
cmux does not restore live process state inside terminal apps. For example, active Claude Code/tmux/vim sessions are not resumed after restart yet.
Star History
<a href="https://star-history.com/#manaflow-ai/cmux&Date"> <picture> <source media="(prefers-color-scheme: dark)" srcset="https://api.star-history.com/svg?repos=manaflow-ai/cmux&type=Date&theme=dark" /> <source media="(prefers-color-scheme: light)" srcset="https://api.star-history.com/svg?repos=manaflow-ai/cmux&type=Date" /> <img alt="Star History Chart" src="https://api.star-history.com/svg?repos=manaflow-ai/cmux&type=Date" width="600" /> </picture> </a>Contributing
Ways to get involved:
- Follow us on X for updates @manaflowai, @lawrencecchen, and @austinywang
- Join the conversation on Discord
- Create and participate in GitHub issues and discussions
- Let us know what you're building with cmux
Community
Founder's Edition
cmux is free, open source, and always will be. If you'd like to support development and get early access to what's coming next:
- Prioritized feature requests/bug fixes
- Early access: cmux AI that gives you context on every workspace, tab and panel
- Early access: iOS app with terminals synced between desktop and phone
- Early access: Cloud VMs
- Early access: Voice mode
- My personal iMessage/WhatsApp
License
cmux is open source under GPL-3.0-or-later.
If your organization cannot comply with GPL, a commercial license is available. Contact [email protected] for details.