> Its based on wireguard and seems even better performance wise.

I hadn't considered that, but it makes sense. Since ZeroTier is layer 2, I'd expect it to become a leaky abstraction (at least for performance) in certain cases where algorithms are expecting other layer 2 hardware to be essentially directly connected with a wire when in reality they're connected over the internet.

What algorithms you have in mind? That would be a bad assumption, since layer 2 can be ethernet, but it may be i2c, or slip, or spacewire... Layer 2 does not mean "close" or "fast".

Yeah, tailscale does look nice, only one user on the free tier was a deal-breaker for me though.