cmux – open-source terminal optimized for multitasking with coding agents

Summary: cmux is a native macOS terminal built on Ghostty that supports multitasking with coding agents through vertical tabs, notifications, and a built-in browser. It enhances agent interaction by highlighting panes needing attention and integrates a scriptable CLI for browser automation.

What it does

cmux uses libghostty for terminal rendering and reads existing Ghostty configurations. It features vertical tabs, blue glowing rings around active panes, and a built-in browser that allows agents to interact with web elements via CLI commands.

Who it's for

It is designed for developers running multiple coding agent sessions, especially those who require efficient multitasking without Electron or Tauri overhead.

Why it matters

cmux addresses the limitations of generic notifications and GUI orchestrators by providing contextual alerts and customizable layouts in a performant native macOS terminal.