If you are looking for cross-platform FOSS P2P, ProtocolLabs' (makers of IPFS) https://libp2p.io https://libp2p.io (P2P conns over TCP, UDP, QUIC, WebSockets, W

If you are looking for cross-platform FOSS P2P, ProtocolLabs' (makers of IPFS) https://libp2p.io https://libp2p.io (P2P conns over TCP, UDP, QUIC, WebSockets, WebRTC) with implementations in various languages (Go, Rust, JavaScript) with varying degrees of features is great to have in the toolbox, as well. Unless of course you're sold into a solution like https://tailscale.com https://tailscale.com, who I believe are readying a userspace embeddable implementation of their P2P mesh wireguard overlay network, which then would be a compelling alternative, too, in the not so distant future, especially because of its security posture (though only the clients are FOSS).