A userspace opensource WireGuard implementation in Rust lang for memeory safety and performance. Currently only supported on Linux and macOS. But they are planning to release ios android version as libs are ready.
* Repo: https://github.com/mullvad/gotatunh
* Blog post: 

Mullvad VPN
Announcing GotaTun, the future of WireGuard at Mullvad VPN | Mullvad VPN
GotaTun is a WireGuardยฎ implementation written in Rust aimed at being fast, efficient and reliable.
