I built Payload to make file transfers easy for less-technical users who need large/fast transfers, so I have focused on auto-discovery, drag-and-drop, visually distinct device icons.
It's using Tauri (an "Electron alternative" built on Rust) which keeps my binaries small and bundles to .msi, .dmg, .deb and .appimage. No CLI, iOS or Android support (yet).
The network stack is a separate binary written in Go. It uses mDNS for local network discovery and TLS over TCP or Quic, with a public Ed25519 keypair for each device. The protocol is ad-hoc and symmetrical control stream using JSON and binary data streams. Planning to open source these parts eventually..
Transfers should saturate the local network link. It reaches ~116 MB/s wired at my home, but if you have a >1000 Mbit link, I'd be curious to see how much speed you can squeeze out.
See also: