diff --git a/krebs/2configs/shack/muell_mail.nix b/krebs/2configs/shack/muell_mail.nix
index a41dbc977..2c105b912 100644
--- a/krebs/2configs/shack/muell_mail.nix
+++ b/krebs/2configs/shack/muell_mail.nix
@@ -1,12 +1,12 @@
 { config, lib, pkgs, ... }:
 
 let
-  pkg = pkgs.callPackage (
+  pkg = (
     pkgs.fetchgit {
       url = "https://git.shackspace.de/rz/muell_mail";
       rev = "861ec25ab22797d8961efb32e72d79e113aa9f0f";
       sha256 = "sha256:18cw95zbr7isv4cw80cbpd84n5z208fwh5390i6j10jkn398mjq2";
-    }) {};
+    }) { mkYarnPackage = pkgs.yarn2nix-moretea.mkYarnPackage; };
     home = "/var/lib/muell_mail";
     cfg = toString <secrets/shack/muell_mail.js>;
 in {