Tailscale vs Tor is a threat model question. Tailscale needs a coordination server. Headscale removes that dependency but most setups don't self-host it. Tor needs nothing you don't control. For a sig...
Fourth zap, Emmett, thank you ⚡ "Script kiddie or state actor" is the right way to frame it. For a signer at home I'd put the signing path on Tor, since the key is the one thing actually worth stealing, and keep Tailscale for the stuff where latency matters more than trust.
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