Premail has been able to export your rules for a while. That export exists for sharing: you tune a set of filters, drop the JSON in a forum thread, and someone else loads your recipe into their own install. It does its job well.

It also quietly became the wrong tool for a job people kept using it for. Getting a new laptop. Reinstalling after a wipe. Running the beta build next to the release build and wanting both configured the same way. In every one of those cases you do not want to move your rules. You want to move everything, and a rules file leaves most of it behind.

So Premail now has a second, separate thing: Settings Backup & Restore. One file, every setting, into another installation.

What actually travels

The gap between a rules export and a settings backup is wider than it sounds. A backup carries all of this:

Built-in rules with every threshold and action you have adjusted, plus all of your custom rules
Applied rule packs, in the stack order you put them in
Allowed senders, blocked senders, and your unsubscribe protection list
App settings: mark as read, auto-unsubscribe, Reputation Shield, what happens after an unsubscribe
Your AI provider and model, and optionally the API key
Per-account preferences: enabled or not, Learning or Live mode, auto-unsubscribe, auto-reply and its template, contacts sync
The default state for newly synced contacts, and how you sort the Contacts tab

That last group is the one that used to be the most annoying to redo by hand. If you run four accounts, each with its own mode and auto-reply wording, rebuilding that on a new machine is twenty minutes of clicking that you will get subtly wrong.

What deliberately does not travel

Your email accounts are not in the file. Neither are their passwords or OAuth refresh tokens. Those live in the macOS Keychain, and the entire point of putting them there is that they do not get copied into a JSON file sitting in your Downloads folder.

That shapes the restore order: connect your accounts on the new machine first, then restore your settings on top. Per-account preferences are matched by email address, because account IDs are generated per install and mean nothing across machines. Any account in the backup that you have not connected on the new machine is simply skipped, and Premail tells you how many matched.

The activity log, unsubscribe history, analytics, and saved Subscriptions and Inbox Cleaner scans also stay behind. Those are a record of what one installation did, not a preference. Copying them into a fresh install would only produce a history that never happened there.

The API key question

Your AI provider API key is the one setting where convenience and caution genuinely conflict, so it is a checkbox rather than a default. Leave it off and the backup carries your provider and model choice but no secret, and restoring leaves whatever key is already on the target install untouched. Tick it and the key is written into the file in plain text, which makes a new-machine setup a single step.

If you tick it, treat the file like a password. Keep it off shared drives, and delete it once the restore is done. Premail shows you in the restore confirmation whether the file you picked contains a key, so you always know what you are loading.

How to use it

Both sides live in the Manage Plan tab, under Backup & Restore. Export writes premail-settings.json to your Downloads folder. Import asks you to pick a file, then shows a summary of exactly what is in it, how many rules, how many packs, how many account preferences, whether a key is included, before it changes anything. Confirm and Premail replaces its settings and reloads.

Restore replaces rather than merges. That is the honest behavior for a migration tool: you are asking for this install to look like the other one, not for a negotiated blend of two configurations. If you want to merge one person's rules into your own setup, the rules import in the Rules tab is still the right tool, and it is unchanged.

Two files, two jobs

It would have been tempting to fold this into the existing rules export and ship one button. We did not, because the two files are meant for different audiences. A rules file is something you hand to a stranger. A settings backup contains your model configuration and your per-account preferences, and possibly an API key. Those should not be the same download, and you should never be surprised by which one you just produced.