What you need

Deep C++ and Chromium fork maintenance experience
Shipped or maintained Windows desktop application
Rust proficiency (TUI, networking daemon)
Upstream Chromium contributions a plus
Swift/AppKit curiosity, open-source maintainer background

What you'll do

Own Chromium fork: track upstream, rebase, carry patches
Own cmux on Windows/Linux end-to-end: installer, auto-update, crash reporting
Port Ghostty terminal core and agent features to Windows
Optimize performance: startup, GPU rendering, input latency
Dogfood, test, and verify constantly

cmux is a native macOS terminal built on Ghostty, designed for running multiple AI coding agents in parallel. Hundreds of thousands of developers use cmux to drive their agentic coding workflows.

Check us out at cmux.com and on GitHub.

We're hiring a founding engineer to own cmux on Windows (and Linux) - built on our own fork of Chromium.

What you'll do

Own our Chromium fork: track upstream, rebase cleanly, carry cmux patches (window/input/render integration, terminal surface, agent UI)
Own cmux on Windows/Linux end to end: C++, installer, auto-update, crash reporting
Port the Ghostty-based terminal core and agent-orchestration features (vertical tabs, notification rings, splits, CLI) to Windows
Make performance feel native: startup time, GPU rendering, input latency
Dogfood, test, and verify constantly

Who we're looking for

Deep C++ and real Chromium work - ideally you've maintained a fork: carrying patches, rebasing on upstream milestones, debugging in content/ or blink
Rust a big plus (our TUI and networking daemon are Rust)
You've shipped or maintained a real Windows desktop app
Bonus: upstream Chromium contributions, Swift/AppKit curiosity, open-source maintainer, former founder

Details