Wireguard developer Jason A. Donenfeld has submitted patches of his original VPN implementation to the Linux kernel. That and the fact that Linux kernel maintainer Linus Torvalds praises the quality of the design and the code means that Wireguard will soon be available in the mainline kernel.
Wireguard is a modern and user-friendly alternative to VPN technologies such as IPsec or OpenVPN. Wireguard uses a magnitude less of code which means that it's easier to security audit. For a long time, Wireguard has been offered as a source code module for various Linux distributions. According to Donenfeld, many large Internet companies use Wireguard in production and there are also hardware products that use Wireguard.