gistfile1.txt

grahamc@Morbo> docker run --user 1000:1000 -it --rm layered-on-top:latest                                                                                ~/projects/nixpkgs
total 36
drwxr-xr-x   1 0 0 4096 Dec  4 17:39 .
drwxr-xr-x   1 0 0 4096 Dec  4 17:39 ..
-rwxr-xr-x   1 0 0    0 Dec  4 17:39 .dockerenv
dr-xr-xr-x   2 0 0 4096 Jan  1  1970 bin
drwxr-xr-x   5 0 0  360 Dec  4 17:39 dev
drwxr-xr-x   2 0 0 4096 Dec  4 17:39 etc
drwxrwxrwx   1 0 0 4096 Dec  4 17:39 example-output
dr-xr-xr-x   3 0 0 4096 Jan  1  1970 lib
dr-xr-xr-x   3 0 0 4096 Jan  1  1970 libexec
dr-xr-xr-x   1 0 0 4096 Jan  1  1970 nix
dr-xr-xr-x 249 0 0    0 Dec  4 17:39 proc
dr-xr-xr-x   5 0 0 4096 Jan  1  1970 share
dr-xr-xr-x  13 0 0    0 Dec  4 17:39 sys
total 12
drwxrwxrwx 1    0    0 4096 Dec  4 17:39 .
drwxr-xr-x 1    0    0 4096 Dec  4 17:39 ..
drwxr-xr-x 2 1000 1000 4096 Dec  4 17:39 hi-there

layered-examples.nix

{
  # 10. Create a layered image
  layered-image = pkgs.dockerTools.buildLayeredImage {
    name = "layered-image";
    tag = "latest";
    config.Cmd = [ "${pkgs.hello}/bin/hello" ];
    contents = [ pkgs.hello pkgs.bash pkgs.coreutils ];
  };

  # 11. Create an image on top of a layered image
  layered-on-top = pkgs.dockerTools.buildImage {
    name = "layered-on-top";
    tag = "latest";
    fromImage = layered-image;
    extraCommands = ''
      mkdir ./example-output
      chmod 777 ./example-output
    '';
    config.Cmd = [ "${pkgs.bash}/bin/bash"
      "-c" "export PATH=${pkgs.coreutils}/bin/; mkdir /example-output/hi-there; ls -la /; ls -la /example-output"];
  };
}