Descriptions:
CMAX is a new open-source, native macOS terminal built specifically for agentic engineering — running multiple AI coding agents in parallel within a single, fast interface. Built on top of libGhosty (the GPU-accelerated rendering engine behind the popular Ghosty terminal) and written in Swift, CMAX avoids the sluggishness of Electron-based terminals and delivers what creator David Ondrej calls the fastest terminal he’s ever used.
In this walkthrough, Ondrej covers CMAX’s core features: horizontal and vertical pane splitting (Command+D and Command+Shift+D), independent zoom per pane, multiple named workspaces, an integrated browser panel, and a secondary sidebar — all designed to make running several concurrent Claude Code, Codex, Pi, or Hermes agent sessions feel natural rather than chaotic. One standout capability is that agents can control CMAX itself via CLI commands: Ondrej demonstrates the Pi agent reading a custom CMAX skill file, then autonomously arranging a 2×2 grid of panes and launching three separate Claude Code instances, each assigned a different single-page HTML app to build.
The tool is freely available at cmax.com and is fully open source, making it forkable and inspectable. Ondrej positions CMAX as a middle ground between a traditional terminal multiplexer like tmux and a full IDE — a clean, native solution for developers and non-developers alike who want to coordinate multiple AI agents without wrestling with clunky default terminals.
📺 Source: David Ondrej · Published May 29, 2026
🏷️ Format: Tutorial Demo
