Skip to main content
The Mac app shows the same projects and cards as witness.nu, and it adds one thing a browser can’t do: it runs agent sessions on your Mac. You start a session from a card, and the agent works in your own repositories. You answer it without leaving the project. Sessions are in beta.

​
Install it

1

Download

Press Download for Mac on witness.nu, or Download in the console once you are signed in. The app is signed and notarized, so macOS opens it without a warning, and it runs on Apple silicon and Intel Macs. The landing page shows the macOS version it needs under the button.
2

Move it to Applications

Open the file and drag witness to Applications.
3

Sign in

Press Sign in using your browser. Your browser opens, you sign in there with your witness account as usual, and then it hands you back to the app.
New versions arrive on their own. The app downloads them in the background, and when one is ready, Restart to update appears: at the foot of the sidebar in a project, at the end of the top bar in the console. You can also look for one yourself under Check for Updates… in the app menu. If sessions are running, the app asks before restarting. A session stopped in the middle of its work comes back saying so. That turn is lost, but the conversation isn’t: your next message picks it up. What changed in each version

​
Before your first session

A session runs on your own agent and your own logins, and the app never runs one of its own. While anything is missing, the Sessions page shows Set up sessions on this Mac, a list that takes you through it one command or button at a time:
  • Claude Code or Codex, installed and signed in.
  • A working folder for the project. Your repositories are cloned there, and the first session you start asks whether sessions work in their own copy or in your checkout. You can change it later under Settings, in This Mac. Nobody else sees it.
  • witness in your agent, signed in with your own account, so the session can read and write the project.
  • The GitHub CLI, installed and signed in, so sessions can clone your repositories and open pull requests as you.
  • A default model and mode for your sessions. A mode you pick in a session, Plan aside, becomes where the next ones start; New sessions start in, under Settings in This Mac, shows it.
Once every step is done, the box for your first message appears. The folder is set per project, so a new project asks for its own.

​
Sessions

Open a card and press Start a session. What a session is, what waits on you, and what your team sees of it: Sessions →