You can make an authentication method strong enough on the VPS, multiple factors, even IP block lists so they'd have to do it from your home.

Secondly, you're local machine should encrypt itself if that's your threat model. They can take it while it's still on but if that's actually a concern for you, you can figure out a way to trigger a lock or a shutdown if things change. If it's a stationary machine, it can be easy to notice your environment changing. maybe you can't find the mac addresses of your switch any more, maybe all 10 of your neighbor's ssid info is no longer visible. Perhaps lack of internet is good enough.

Phones are a lot harder because their environment changes a lot more, but you can still check things like has my computer decided to go to lock itself? In the end, if your threat model involves that kind of risk, you can set your devices up to brick themselves or at least shutdown and encrypt themselves.

Last, you'd probably want a device so that you can do the things. A phone and or old laptop with an OS already installed that you can retrieve.

That's an interesting opsec problem. Here is the solution that requires writing more software:

1. Find some friends or people you trust to not sell you out to the police. Ideally, these people should be in another country.

2. Place a server box on their property. This box will be a replica of your every-day home-server and devices.

3. However, in order to stop law enforcement from technically [1] finding this replica-box, you will need to use Tor. This ensures your home-server does not store the ip address or the physical location of the replica-box.

4. If your home-server is taken by law enforcement, you can buy another home-server and use memorized details (or call your friends on a burner phone) to restore a backup from the remote device [2].

[1] Please note that law enforcement can legally compel you with threats of jail time to reveal where these replica boxes are.

[2] Since you will probably be under surveillance, it's unlikely law enforcement will allow you to freely communicate on the internet with new devices and servers.

Regarding [1], do you know Brazilian law? I don't. In any case, the right to not incriminate yourself has been widely adopted, and in principle, could perhaps be invoked here, too.

> but what if the police could get to the same VM via the confiscated devices? I don't know...

This is usually what passwords are for, something you know that cannot be stolen (short of rubber hose cryptography)

Yes. For that I've been thinking of using VeraCrypt's hidden volumes. A volume inside another volume where an adversary cannot see their boundaries, which could allow some plausible deniability for passwords. I guess.

Manually rotated offline backups. Copy all your stuff to an external hard drive and stash it at your least technical friend's place. Go visit them once a week and swap the drive while you're there. You might lose up to a week's work but the bulk of your data will be safe.

If your server has full disk encryption it should be relatively safe against attacks where they just take the device, and so whatever you use to sync should be safe too?

It depends whether you want to preserve your work somewhere so that it cannot be wiped, or if you want to secure it so nobody has access.

In the first case I would set up a "append only" system where you cannot delete anything, just append information. This could simply be a incremental backup system.

Have it managed by someone outside your country, you would just be a user.

In that case if they grab everything they cannot delete what you have there, and the cannot access it as administrator either.

If you want to protect from the second case, its gets much more complicated.

You need to encrypt the systems that hold the data and make it so that the encryption key is wiped from the systems if they are in a panic state. This can go as far as you want: no more Internet (the machine was disconnected), or the trigger on the door of your basement starts a countdown of a few seconds you can only stop by logging in - otherwise the system shuts down (or better, cuts the power).

An extra complication is if you fear that you can be forced to provide decryption keys. In such a case you could either go for dynamic keys that are provided to you by someone else outside your country, though a process that ensures that you are safe.

"you want to preserve your work somewhere so that it cannot be wiped"

This is my biggest concern. Confiscated devices are never returned to their owners.

Pick a VPS from a hosting provider outside of your home country (Brazil in this case). Use it to hold encrypted backups. Either a Syncthing instance configured as untrusted, or just btrfs send incremental snapshots and filter the stream through gpg on the way out.

I suppose your other issue is making sure that payments still get made in a timely manner if for some reason your home country freezes your assets or you get arrested. I guess it just depends on what you're up to and how paranoid you are. Personally I wouldn't worry about it too much. You could probably just deposit a portable hard drive with a friend or relative periodically if you're that concerned.