I'll bite: how do we take advantage of ZFS layering if not via the docker-style layering?

I find dockerfile layering to be unsatisfying because step 5 might depend on step 2 but not 3 or 4... the linearisation of a DAG makes them harder to maintain and harder to cache cleanly (with us also having monster single-line CMDs all in the main of image results).

So is there a better way that people are using?