An always-on device

Keeps your frames running and your changes up to date while your other devices sleep.

A computer that stays on keeps your frames running and your changes up to date while your other devices sleep. You don't need one to use Seamside.

Why it matters

Frames that run on it keep working at night, on weekends and while you travel.
It keeps up with every change, so a laptop or phone that wakes up gets the latest from it.
It keeps a full copy of everything you have, so it's also one more place your work lives.

There are two good choices. Pick the one that fits how you live.

A computer at home: a desktop you leave on, a spare laptop, a home server or a Raspberry Pi. It's yours, your files stay on it, and it costs nothing more.
A rented server: a small Linux server from a provider such as DigitalOcean, Vultr or Hetzner. It's online all the time and costs a few dollars a month.
A rented server runs on someone else's hardware, so Seamside adds it as a shared device. Its folder is encrypted on its disk, and the key stays on your other devices.
When a shared device restarts, it asks one of your devices for its key. You approve each ask in Seamside, or let it get its key without asking.
When it joins, choose Always on. You can carry it there in Devices later too.

Either kind can be set up either way: with the app if it has a screen, or with a command if it doesn't.

Install Seamside on it from the download page.
On a computer you already use, open Devices and choose Add a device.
On the new computer, choose I already use Seamside, then scan the code or paste the link.
When it asks to join, check the mark matches. Choose Accept as mine if only you use it, or Accept as a shared device.

On a computer you already use, open Devices, choose Add a device, then Set it up with a command. Copy the command.
Connect to the new computer, for example over SSH, then paste the command and run it as root.
When it asks to join, check that the mark matches, then choose Accept as a shared device if it's rented or shared.

shared device: a computer you rent or share. It keeps your spaces and runs your frames, but never holds your identity, and you can remove it any time.