{
  writeShellApplication,
  active,
  distroFile,
  buildGoModule,
  lib,

  go,
  packer,

  ...
}:

let
  inherit (builtins) concatStringsSep map;
  bin = buildGoModule {
    pname = "cache";
    version = "0.0.0";
    src = ./cache;
    vendorHash = "sha256-Mtq6BIlBNxI28eoLPfayov5uUqC4gMK+4ib6VKjyAlU=";
    #vendorHash = lib.fakeHash;
    meta.mainProgram = "main";
  };
in
writeShellApplication {
  name = "cache-isos";
  runtimeInputs = [
    go
    packer
  ];
  text =
    ''
      set -o pipefail
      function list_isos {
    ''
    + (concatStringsSep "\n" (
      map (d: ''
        url=$(echo var.iso.url | packer console -var-file="${d}" -config-type=hcl2 sources/)
        sha=$(echo var.iso.checksum | packer console -var-file="${d}" -config-type=hcl2 sources/)
        distro=$(echo var.distro | packer console -var-file="${d}" -config-type=hcl2 sources/)
        echo "$url" "$sha" "$distro"
      '') (lib.unique (lib.map distroFile active))
    ))
    + ''
      }

      list_isos | ${lib.getExe bin}
    '';
}