Tailscale on the Steam Deck

This process is derived from the official guide, but lightly tweaked to make the process smoother and produce an installation that comes up automatically on boot (no need to enter desktop mode) and survives system updates.

Installing Tailscale

⚠️ This process will probably fail if you are accessing the terminal over Tailscale SSH, as it seems to be locked in a chroot jail. You should start and connect through the standard SSH server instead. Suggestions for how to fix this are welcomed.

Download the attached tailscale.sh and tailscaled.service files to your Deck.
Copy the tailscaled.service file to /etc/systemd/system/.
Run sudo bash tailscale.sh to install Tailscale (or update the existing installation).
Run sudo tailscale up --qr --operator=deck --ssh to have Tailscale generate a login QR code. Scan the code with your phone and authenticate with Tailscale to bring your Deck onto your network.

How it works

It uses the same system extension method as the official guide, but we put the tailscaled.service file directly in /etc/systemd/system/ because it's actually safe to put things there. Changes in /etc/ are preserved in /var/lib/overlays/etc/upper/ via an overlayfs, meaning that they survive updates.