First Launch
This is expected. You need to allow it once.
Right-click Open#
Control-click Justty.app, choose Open, then click Open again in the dialog. macOS remembers the decision, so subsequent launches are normal double-clicks.
This is the recommended path because it goes through the system's own consent flow.
Clear quarantine instead#
If you prefer the terminal, remove the quarantine attribute that Safari or your browser attached to the download:
xattr -dr com.apple.quarantine /path/to/Justty.app
open /path/to/Justty.appHomebrew installs do this automatically in the cask's postflight, so this step only applies to manual downloads.
What you get#
On first launch JusTTY opens one window with one tab running your login shell. The shell comes from your user account ($SHELL, falling back to passwd) and starts as a login shell through Ghostty's .exec backend, so your .zprofile or .bash_profile runs the way it does in any other terminal.
A config file is created at ~/.config/justty/config.yml with defaults. You never have to edit it by hand; the Settings window writes to it. See config.yml if you want to.
First things to try#
| Action | Keys |
|---|---|
| New tab | ⌘T |
| New window | ⌘N |
| Open Settings | ⌘, |
| Find in scrollback | ⌘F |
| Zoom the font | ⌘+ / ⌘− / ⌘0 |
The full list is in Keyboard Shortcuts.
If it still will not open#
Head to Troubleshooting. The common causes are an older macOS than 15.6, or an incomplete download.