QUIC is a transport-level protocol developed by Google and intended to improve/replace TCP in settings where you want to run something like HTTP on the topmost layer.

Implementation-wise, it actually runs on top of UDP.

One thing that stands out with this library is the neckbreaking pace of deprecation of old versions of QUIC. I know it's an experimental protocol, so they have free reign, but a lot of the 'new web', and a lot of what Google/Chrome puts out, deprecates old versions very, very fast.