ZeroTier proof-of-concept
This package adds ZeroTier support to any of your existing setups. Just add this package as a child package, configure a network and then go to your ZeroTier management dashboard to authorize your devices once they automatically joined.
The ZeroTier daemon also accepts adding external default routes, so you can add an "exit node" as described here to route all traffic through your own router.
Note that the persistent websocket connection to the info-beamer hosted backend will have to timeout when you overwrite the default route. So your devices might appear offline for a minute or two.
info-beamer P2P also works and should be able to reach all nodes in your network.