macOS blocks atbridge (Gatekeeper)

In short: atbridge is now signed with an Apple Developer ID certificate and notarized by Apple, so macOS Gatekeeper should let it run without any warning. If an older, unsigned version is blocked, reinstall with the script (curl -fsSL https://atbridge.ai/install.sh | sh) or clear the quarantine flag with one xattr command.

Tip

On a current build you shouldn’t see this at all. atbridge binaries are code-signed with an Apple Developer ID and notarized by Apple — macOS recognizes them as coming from an identified developer. The steps below are only needed if you installed an older unsigned build before signing was introduced.

If macOS shows “atbridge can’t be opened”, “atbridge is damaged and can’t be opened”, or “unidentified developer”, you’re almost certainly on an older, unsigned build — that message is macOS Gatekeeper applying its usual caution to an app it can’t recognize.

Why this could still happen

Every app you download on macOS gets a hidden quarantine flag. Before atbridge was notarized, Gatekeeper played it safe on the first launch and blocked the unsigned binary until you confirmed you trusted it. Current builds are notarized, so Gatekeeper recognizes them — but a binary you downloaded before the signed release still carries the old quarantine flag and no signature, so macOS keeps blocking that specific copy until you replace it or clear the flag.

Note

This was always a precaution, not a virus alert. Every atbridge download is also verified during install by SHA-256 checksum and a minisign signature — if a single byte were tampered with, the installer refuses to run.

Fix it (older unsigned build)

Reinstall (easiest)

Reinstalling pulls the current signed + notarized build, which Gatekeeper accepts, and replaces the old unsigned binary:

curl -fsSL https://atbridge.ai/install.sh | sh

That’s the whole fix. It installs to ~/.atbridge/bin/atbridge, puts atbridge on your PATH, and registers the Thunderbird bridge.

Clear the flag on the binary

If you’d rather keep the binary you have, clear the quarantine flag and mark it executable:

xattr -dr com.apple.quarantine ~/.atbridge/bin/atbridge
chmod +x ~/.atbridge/bin/atbridge

Adjust the path if you saved it elsewhere (e.g. ~/Downloads/atbridge). The -dr removes the attribute recursively; chmod +x makes it runnable. (Reinstalling to get the notarized build is still the cleaner fix.)

Allow from System Settings

1. Double-click the atbridge binary. When macOS blocks it, click Cancel (not “Move to Trash”).

2. Open System Settings → Privacy & Security. Scroll to the Security section — you’ll see “atbridge was blocked to protect your Mac.” Click Open Anyway.

3. Confirm once more when prompted. macOS remembers your choice for this binary.

Verify

atbridge --version

A version string means macOS is letting atbridge run. If you’re setting up the Thunderbird bridge, follow it with:

atbridge bridge ping

Caution

Don’t disable Gatekeeper system-wide (spctl --master-disable) — you don’t need to, and it lowers your Mac’s protection for everything. The per-binary fixes above are all that’s required.

Where to go next

• Install atbridge
• When activation fails
• When your AI can’t find anything

Faster: ask the community

For “how do I…” questions you will usually get a quicker answer — and help the next person with the same question — in Discord. Anything tied to your account, billing, or a bug is better as a support ticket, where we reply by email.