diff --git a/hosts/common/programs/wob/default.nix b/hosts/common/programs/wob/default.nix
index 81bfa2bf..a8f42189 100644
--- a/hosts/common/programs/wob/default.nix
+++ b/hosts/common/programs/wob/default.nix
@@ -11,7 +11,7 @@ let
   wob-pulse = pkgs.static-nix-shell.mkBash {
     pname = "wob-pulse";
     src = ./.;
-    pkgs = [ "gnugrep" "gnused" "pulseaudio" ];
+    pkgs = [ "coreutils" "gnugrep" "gnused" "pulseaudio" ];
   };
   cfg = config.sane.programs.wob;
 in
diff --git a/hosts/common/programs/wob/wob-pulse b/hosts/common/programs/wob/wob-pulse
index 1ba71925..2139aa4c 100755
--- a/hosts/common/programs/wob/wob-pulse
+++ b/hosts/common/programs/wob/wob-pulse
@@ -1,5 +1,7 @@
 #!/usr/bin/env nix-shell
-#!nix-shell -i bash -p gnugrep -p gnused -p pulseaudio
+#!nix-shell -i bash -p coreutils -p gnugrep -p gnused -p pulseaudio
+
+set -e
 
 debug() {
   printf "$@" >&2