Most macOS upgrades go fine. The ones that don't usually fail for boring, predictable reasons: a backup that wasn't really a backup, a VPN client that stopped loading, a NAS that suddenly won't mount. Golden Gate adds a few new ones, because it removes several pieces of old infrastructure along with Intel support.

This checklist takes about 30 minutes. Do it before the upgrade, because Golden Gate has no uninstall. Going back to Tahoe means erasing your Mac and restoring from a backup made before you upgraded.

1. Make a backup, then prove it works

A backup you've never restored from is a hope, not a backup.

Run a fresh Time Machine backup to an external drive or a network share, then open Time Machine, browse back to that backup, and restore a single file somewhere harmless, like your Desktop. If the file comes back intact, the chain works.

Check where your backups actually go:

tmutil destinationinfo

Look carefully at the result. Golden Gate no longer supports Time Machine backups to AirPort Time Capsule, and it drops the Apple Filing Protocol entirely. If your destination is a Time Capsule, or its URL starts with afp://, your backups will stop working the moment you upgrade, and that includes the backup you'd need to roll back.

Fix it now:

  • Switch your NAS share to SMB and disable AFP on the NAS. Leaving AFP enabled alongside SMB has caused connection problems for Golden Gate Macs.
  • If you use a Time Capsule, move backups to a USB drive or an SMB-capable NAS before upgrading.
  • Keep your last pre-upgrade backup. Don't let Time Machine thin it out in the first week.

If you'd rather have a second safety net, a bootable clone on a separate drive is the fastest way back if you do need to roll back.

2. Find the extensions that could stop loading

This is the step that decides whether your Mac works on Monday morning.

Golden Gate drops support for kernel and system extensions that depend on older Intel-era components. The software most likely to be affected:

  • VPN clients
  • Antivirus and endpoint security (EDR) agents
  • USB, audio interface, and network drivers
  • Filesystem extensions
  • Backup software
  • Virtualization tools
  • Smart-card and enterprise authentication middleware

List what you have. Third-party kernel extensions:

kmutil showloaded 2>/dev/null | grep -v com.apple

System extensions, which is where modern VPNs and security tools live:

systemextensionsctl list

You'll also find them in System Settings > General > Login Items & Extensions.

For every entry, find the vendor's compatibility statement for macOS 27. You're looking for explicit support for the release version, not "we're testing" and not a forum post saying it worked in beta 6. If the tool is on a work Mac, ask IT; many companies hold major upgrades until their security stack is certified.

3. Check your network storage and shared folders

AFP is gone, so anything that mounts over afp:// needs to move. That includes old NAS units, shares from older Macs, and saved Finder connections you set up years ago and forgot about.

See what's currently mounted and how:

mount | grep -E "afp|smbfs"

Check your saved servers too: in Finder, choose Go > Connect to Server and look through the favorites and recent servers for afp:// addresses. Replace them with the smb:// equivalent after enabling SMB on the server.

If a device only speaks AFP, it's time to replace it or keep one Mac on Tahoe to talk to it.

4. List your Intel-only apps

Intel apps still run on Golden Gate through Rosetta 2, which is no longer installed by default: macOS prompts you to install it the first time you open an Intel app. If you use Intel-only audio plug-ins or other components that load inside another app, install it right after upgrading with softwareupdate --install-rosetta --agree-to-license, because there may be no prompt.

The deadline is next year. Apple has confirmed that Intel-based apps won't open in macOS 28, except for a subset of older, unmaintained games. This is the year to find out what you depend on.

Hold Option, open the Apple menu, and choose System Information. Go to Software > Applications and sort by the Kind column. Anything marked Intel is on your list.

For each one, check whether a native version exists, whether the developer is still around, and what you'd replace it with. Nothing needs to happen before the upgrade, but you'll be glad to know now rather than next September.

5. Update apps and write down what you'll need to sign back in

Update everything before the upgrade, not after. Developers ship compatibility fixes in the days around release, and an outdated app is the most common reason something "broke" after an OS update.

  • App Store: open the Updates section and install everything.
  • Apps outside the App Store: use each app's Check for Updates menu item.
  • Homebrew users: run brew update && brew upgrade.

Utilities that change system behavior deserve extra attention: window managers, mouse and trackpad remappers, clipboard tools, and menu bar managers. Some users have already reported Mission Control and Spaces actions failing through third-party mouse utilities on Golden Gate. Check each tool's release notes or issue tracker for 27.0 support.

Menu bar managers are the hardest hit. Golden Gate draws the entire menu bar as a single window instead of one window per icon, and the tools that hid icons depended on that old behavior. Bartender, Ice, Hidden Bar, and similar apps all broke during the beta. Some have Golden Gate builds, some don't, and none of them use an official API. If your menu bar is carefully arranged, screenshot it before upgrading so you can rebuild it.

While you're at it, make sure you can reach license keys, two-factor recovery codes, and your password manager from another device. An upgrade rarely signs you out of anything, but if you do end up restoring, you'll need them.

6. Make room and check special setups

Aim for about 40 GB of free space. The installer is around 18 GB, and the upgrade needs working room beyond that. Check what's truly free, not what Finder calls available: 

df -h /System/Volumes/Data

Two setups need specific attention:

  • Dual-boot with Asahi Linux. During the beta, Golden Gate was reported to prevent booting into the Linux partition, with data intact. The workaround was booting from an older macOS volume. Check the Asahi project's current status first.
  • OpenCore Legacy Patcher on unsupported Macs. Golden Gate doesn't support Intel Macs at all, and patched Macs shouldn't try. Turn off automatic updates so the Mac doesn't attempt anything unexpected.

7. Pick your moment

Don't upgrade the night before a deadline, a flight, or a presentation.

The install itself takes a while, and the first day or two afterward is slower than normal. Spotlight rebuilds its index, Photos re-analyzes your library, Mail re-indexes, and Apple Intelligence downloads its models. Fans, heat, and battery drain in that window are normal. Keep the Mac plugged in overnight after upgrading and let it finish.

If you've decided to wait, make sure the Mac doesn't decide for you. Go to System Settings > General > Software Update, click the info button next to Automatic Updates, and turn off automatic installation of macOS updates. Security responses can stay on.

The checklist

  • Fresh backup, and one file successfully restored from it
  • Backup destination isn't a Time Capsule or an afp:// share
  • Third-party kernel and system extensions listed and confirmed with vendors
  • AFP shares and saved servers switched to SMB
  • Intel-only apps listed
  • All apps updated; license keys and recovery codes reachable
  • About 40 GB actually free
  • Asahi or OpenCore setups checked
  • A quiet day or two ahead, with the Mac plugged in overnight

If every box is ticked, the upgrade is very unlikely to surprise you. If one of the extension or backup items can't be ticked yet, that's your answer: wait until it can.