NixOS's virtualisation module can use either Docker or Podman and if Podman is enabled it has a Docker compatiblity mode (via `virtualisation.podman.dockerCompat = true`) that puts symlinks in all the right places (`docker` binary, `docker.sock`) so that software doesn't even know it's not running vanilla Docker :)

Really not seeing the point of using docker-anything on NixOS here. Shouldn’t Nix already be able to isolate dependency trees from each other? Why would you want to duplicate all those files yet again in a docker image?

Sounds good in theory but there are a couple reasons to use docker. The first is that there are endless packages already prepared for docker that you'd have to manually set up on any OS, let alone Nix. For instance "itzg/minecraft-server". The second is that if you use docker you've got control of where all the stateful volume data sits. I keep it all in one folder for easy backup. The rest of the system is fully managed by nix.