Forget the server, what especially worries me is the client.
For some weird reason the GUI clients for Windows, macOS and iOS are closed-source.
I never understood exactly why that is, considering that the Linux and Android ones are fully open.
The fact that there isn't a reason documented anywhere certainly worries me.
https://github.com/tailscale/tailscale/wiki/Tailscaled-on-ma...
I do that mostly because it's running as a LaunchDaemon.
> Forget the server
Pop the headscale server in and you get a fully FOSS system.
https://github.com/juanfont/headscale
That I don't do, because the coordination server, the relay system (which you can also self-host), and the server side UI are really good.
And also the public behaviour of the persons working at Tailscale as well as Tailscale's approach towards FOSS generally increase my level of trust in them. IOW they strike me as Nice Folks(TM), and if Nice Folks(TM) don't inspire confidence to you then you probably want to run the whole thing as described above.
I mean, please read this in its entirety. They even have a "Encouraging Headscale" section.