Nice work on this! If you cut out a bunch of the features supported by other containerization systems, the code gets quite short. My first one was in C and only a couple hundred lines. I worked on a full-featured rust container runtime while I was at Oracle. It is compatible with the oci-runtime spec, so can be used as a runtime for docker or kubernetes. The most up to date fork is at https://github.com/drahnr/railcar if you want to take a look at it for any ideas.