Overlayfs, aufs, etc. are really irrelevant to containers. They are used in Docker because it's built around opaque binary disk images that do not compose, whi

Overlayfs, aufs, etc. are really irrelevant to containers. They are used in Docker because it's built around opaque binary disk images that do not compose, which I believe is a big flaw, but it doesn't have to be this way. For example, GNU Guix has a container implementation that does not use disk images at all but still achieves system-wide deduplication of software across all containers running on the host via simple bind mounts.