Harness

Judgement

What it is

Complete system

What it does

A native macOS terminal with its own GPU renderer and a session host that keeps shells running after you quit the app. It watches coding agents such as Claude Code and Codex and flags when one needs attention, and has a CLI and a daemon usable over SSH, including on Linux.

Adopt it when

You want a Mac terminal whose sessions survive app restarts and that notices when an agent is waiting.

Watch out

The GUI is macOS only, the project is five months old, and its agent hooks follow third-party tools that change often.

Ready for

Usable

Runs as

Desktop app and command line

Built with

Swift, Python and Metal

How established

New: started 5 months ago, latest release v2.4.1.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-06 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Harness → Swift → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

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