Install on macOS

Probe ships as a signed and notarized DMG for macOS. The whole install — from download to a running proxy with your system traffic flowing through it — takes under a minute.

System requirements

• macOS 12 Monterey or later.
• Apple Silicon (M1/M2/M3/M4) or Intel. Probe ships a single universal binary; you don’t need to pick a build.
• About 200 MB of free disk space for the app and its data directory.
• Administrator access on first launch so Probe can flip the system HTTP/HTTPS proxy.

Probe runs without the App Sandbox — that’s required to set the system proxy and to bind the local listening port. As a result it’s distributed outside the Mac App Store.

Install

1. Go to the Download page and click Download for macOS. You’ll get a file named like probe-x.y.z.dmg.

2. Double-click the DMG to mount it. A Finder window opens with Probe.app on the left and an Applications shortcut on the right.

3. Drag Probe.app onto the Applications shortcut. Wait for the copy to finish, then eject the DMG.

4. Open Applications in Finder and double-click Probe.

First launch and Gatekeeper

The first time you open Probe, macOS Gatekeeper checks the signature and notarization ticket. The app is signed with a Developer ID Application certificate and stapled, so on most setups it opens directly.

If you see “Probe.app can’t be opened because Apple cannot check it for malicious software” (this can happen on stricter security policies or older macOS releases):

1. Click Done on the warning to dismiss it.

2. Open System Settings → Privacy & Security.

3. Scroll to the Security section. You’ll see a line about Probe being blocked, with an Open Anyway button next to it.

4. Click Open Anyway, then confirm with your password or Touch ID.

You only need to do this once. After that, Probe launches like any other app.

Tip

If Open Anyway doesn’t appear, right-click Probe.app in Applications and choose Open from the menu. This is the per-app override and it works even when the system-wide setting is strict.

What happens on first launch

Probe is intentionally aggressive about getting you to a working state:

• The proxy starts immediately on 0.0.0.0:9099. You don’t need to click anything.
• Your system HTTP/HTTPS proxy is set automatically via networksetup. macOS may prompt you for your password the first time.
• The CA certificate HTTP server starts on port 9098 so you can install the cert on phones and other devices on your LAN.
• The data directory is created at ~/.probe/ — it holds your CA, sessions, scripts, environments, and settings.

Look at the toolbar: you’ll see your machine’s IP and port (e.g. 192.168.1.42:9099) and a separate CA URL (e.g. http://192.168.1.42:9098). Those are the values you’ll point your phone or VM at later.

When you click Stop, Probe restores the system proxy settings to what they were before. If Probe quits unexpectedly, the proxy is also restored on the next clean launch.

Caution

If you’re upgrading from a much older build that wrote to ~/.guide_proxy/, Probe migrates that directory to ~/.probe/ automatically on first launch. You don’t need to copy anything by hand.

Auto-update

Probe checks for new releases in the background and updates itself in place. There’s no separate updater app and no Sparkle prompt to click through.

When a new version is available:

1. Probe downloads the signed DMG from S3 in the background.
2. It mounts the DMG, copies the new .app over the existing one in /Applications, and unmounts.
3. The next time you launch Probe (or immediately, if you accept the relaunch prompt), you’re running the new version.

If the release is marked as a minimum version in the manifest, Probe shows a non-dismissible update dialog at startup — there’s no Later button. This is reserved for builds that fix protocol-level bugs or breaking certificate changes.

After an update, Probe shows a short changelog dialog summarizing what’s new. You can re-read it later from the Help menu.

Uninstall

To remove Probe:

1. Quit the app — this restores your system proxy.
2. Drag Probe.app from Applications to the Trash.
3. (Optional) Remove ~/.probe/ to delete your CA, sessions, and settings.

Removing ~/.probe/ invalidates the CA on every device you trusted it on — you’ll need to re-install the cert if you reinstall Probe later.

Next steps

First Capture Make your first request and see it in the log.

Certificate Setup Install the CA so HTTPS bodies are readable.

Quick Tour 60-second walkthrough of the UI.