> The client is completely open source on open source operating systems.

IOW it's by and large the GUI part that is not open source. Personally I prefer to run it as a system LaunchDaemon than a user LaunchAgent anyway.

> We never open sourced our coordination server because Headscale beat us to it.

I seem to recall reading that another reason was that there was intent to open source it but it made little sense as far as running it because its code was written for (and coupled to) Tailscale's heavy duty infra. So Headscale beat Tailscale to it by providing not just code but code that could work on much wider contexts.