anchor.diff:          use-substitutes = ${if cfg.useSubstitutes then "1" else "0"}
         '';
   
  -    environment.systemPackages = [ cfg.package ];
  +    environment.systemPackages = [ hydra-package ];
   
       environment.variables = hydraEnv;
   
  
positive.code:           PGPASSFILE = "${baseDir}/pgpass-queue-runner";
          };
          serviceConfig =
            { ExecStart = "@${cfg.package}/bin/hydra-notify hydra-notify";
              # FIXME: run this under a less privileged user?
              User = "hydra-queue-runner";
              Restart = "always";
  
negative.code:           chown hydra.hydra ${cfg.gcRootsDir}
            chmod 2775 ${cfg.gcRootsDir}
          '';
          serviceConfig.ExecStart = "${hydra-package}/bin/hydra-init";
          serviceConfig.PermissionsStartOnly = true;
          serviceConfig.User = "hydra";
          serviceConfig.Type = "oneshot";
  