The tools

Mackup

Mackup backs up application preferences and dotfiles to a synced storage location of your choice, and, more importantly here, it produces a manifest of the apps it manages. That manifest doubles as an inventory of what’s installed on the machine.

Openboot

Openboot is a bootstrap script for fresh Mac setups. It installs your development tooling and, as a bonus, applies the Finder and system preference tweaks I’d otherwise configure by hand on every new machine.

Step 1: Snapshot the old machine

On the outgoing MacBook Air:

brew install mackup
mackup backup

This writes preferences and a manifest to ~/.mackup and a .mackup.cfg file lets you point the storage engine anywhere. I pointed mine at a folder synced by Synology Drive to my local NAS, and copied my home directory and Documents the same way.

Step 2: Set up the new machine clean

On the new MacBook Air, I went through the standard macOS setup without restoring anything from Time Machine or Migration Assistant, then ran openboot to configure my dev environment and system settings in one pass:

curl -fsSL https://raw.githubusercontent.com/openbootdotdev/openboot/main/install.sh | bash

(Check the openboot repo for the current install command, since these things evolve.) Beyond the dev tooling, openboot also applied the Finder and system preference tweaks I usually set by hand, which was a nice bonus.

Step 3: Restore the app inventory

Once Synology Drive synced the .mackup folder to the new machine, I installed Homebrew and mackup, then restored:

brew install mackup
mackup restore

Mackup restores preferences for everything it manages, and just as usefully, it prints out the apps that were on the old machine but not installed through Homebrew. That short list became my to-do list: reinstall those via brew install (or brew install –cask) so the next migration is even simpler.

Why bother

Skipping the full disk migration meant no years-old cruft rode along to the new machine. And centralizing on Homebrew means a single brew bundle dump going forward gives me a complete, versioned inventory of my apps, ready for whenever I need to rebuild again.