First I'd heard of this project; here's an introduction from the author: https://fwsgonzo.medium.com/tinykvm-the-fastest-sandbox-564a...
TinyKVM: Fast sandbox that runs on top of Varnish - https://news.ycombinator.com/item?id=43358980
Deno Under TinyKVM in Varnish - https://news.ycombinator.com/item?id=43650792