[mplanchard]

To be fair to the authors, this IS a problem, albeit one they phrased poorly, especially with building docker images via nix. The store winds up containing way more than you need (eg all of postgres, not just psql), and it can be quite difficult to patch individual packages. Derivations are also not well-pruned in my experience, leading to very bloated docker images relative to using a staged Dockerfile.

Image size isn’t something we’ve focused a lot on, so I haven’t spent a ton of time on it, but searching for “nix docker image size” shows it to be a pretty commonly encountered thing.