gistfile1.txt

{ stdenv,  symlinkJoin, dockerTools, coreutils, writeScript, glibcLocales,
  metadrift }:

let

  metadriftConfig = {
      environment.systemPackages = [ metadrift ];
    };

  minimalDocker =
    {
      imports = [ <nixpkgs/nixos/modules/profiles/minimal.nix> ];
      boot.isContainer = true;
      environment.etc.machine-id.text = "00000000000000000000000000000000";
    };
  eval =
    import <nixos/lib/eval-config.nix> {
      modules = [
        minimalDocker
        metadriftConfig
      ];
    };
  system =
    eval.config.system;

  rootDir = "/data";
  homeDir = "${rootDir}/var/lib/metadrift";
  logDir = "/data/log";

  port = 8743;

  entrypoint = writeScript "entrypoint.sh" ''
    #!${stdenv.shell}

    set -e

    exec ${metadrift}/bin/metadrift-exe --port ${toString port}
  '';

in
dockerTools.buildImage rec {
  name = "metadrift";

  contents = symlinkJoin {
      name = "${name}-contents";
      paths = [
          system.build.etc
          system.path
        ];
  };

  config = {
    Cmd = [ "${entrypoint}" ];
    Env = [ "PATH=${coreutils}/bin:$PATH"
            ''LOCALE_ARCHIVE="${glibcLocales}/lib/locale/locale-archive"''];
    ExposedPorts = {
      "${toString port}/tcp" = {};
    };

    WorkingDir = "/data";
    Volumes = {
      "/data" = {};
    };
  };
}