zerotier/ZeroTierOne ? reverse-engineered prompt

Build me a ZeroTier style networking tool that lets my devices, servers, VMs, and containers join the same private virtual network from anywhere, like they are plugged into the same office switch.

I want a small background service and a simple command line control tool. A user should be able to create or join a network, see their device identity, list connected peers, leave a network, and check connection status. Traffic between devices should be encrypted, prefer direct peer to peer connections when possible, and fall back to relay behavior when direct connections cannot be made.

Please keep it practical and runnable on a normal developer machine first, with clean build instructions, basic self tests, and clear docs for installing, starting the service, joining a network, and troubleshooting. Focus on a working minimal version before adding advanced rules or management features. Look up current networking and platform docs online if you need to.