We also created a simple tool called kindbox that runs K8s inside system containers deployed with Docker + Sysbox. It's a simple bash script around "docker run --runtime=sysbox" commands. It does some of the same things that K8s.io KinD tool does, but using simpler Docker images and without using privileged containers. It's meant as a reference example to show developers how to deploy K8s clusters using Docker + Sysbox.
You can find kindbox here if you are curious: https://github.com/nestybox/kindbox