This project started off as a side-project on secure code execution because I wanted to figure out Repl.it and HackerRank worked. I tried experiments with different technologies like Firecracker [1], AWS Lambda [2] and gVisor [3]. They are all great technologies but I ended up with a solution using a combination of VMs and Docker containers to execute user generated code.
I guess great minds think alike! It's gratifying to see the smart engineers @ Google use a similar solution to solve the security problem. Unfortunately, it seems Crostini is tied heavily to ChromeOS.