nixos-config/home-manager/roles/kassandra.nix

{pkgs, ...}: let
  dhallFiles = pkgs.runCommand "kassandra-config-src" {} ''
    mkdir $out
    ${pkgs.kassandra}/bin/kassandra2 print-types > $out/types.dhall
    ln -s ${./kassandra}/{config,backend}.dhall $out
    ln -s ${pkgs.privateFile "kassandra-uiConfig.dhall"} $out/uiConfig.dhall
  '';
  backend = pkgs.dhallPackages.buildDhallPackage {
    name = "kassandra-backend-config";
    code = "${dhallFiles}/backend.dhall : (${dhallFiles}/types.dhall).BackendConfig";
    source = true;
    dependencies = [pkgs.dhallPackages.Prelude];
  };
  standalone = pkgs.dhallPackages.buildDhallPackage {
    name = "kassandra-standalone-config";
    code = "${dhallFiles}/config.dhall : (${dhallFiles}/types.dhall).StandaloneConfig";
    source = true;
    dependencies = [pkgs.dhallPackages.Prelude];
  };

  dhallResult = pkgs.runCommand "kassandra-config" {} ''
    mkdir $out
    ln -s ${backend}/source.dhall $out/backend.dhall
    ln -s ${standalone}/source.dhall $out/config.dhall
  '';
in {
  xdg.configFile =
    if pkgs.withSecrets
    then {
      kassandra.source = dhallResult.out;
    }
    else {};
}