Servers on your local network now connect on macOS 15 and later once Serverus is allowed under System Settings → Privacy & Security → Local Network.
In 1.6.2, turning that switch on could have no effect: connections to a Raspberry Pi, a NAS or any other LAN host kept failing with "No route to host". The macOS build carried only a minimal signature, so macOS did not connect the switch you turned on to the app that was running. The app is now signed with its own identifier, and the switch applies to it.
After updating, macOS may ask for local network access again. Allow it, or turn Serverus off and on again in that list.