diff --git a/lib/update-system.nix b/lib/update-system.nix
index 146bbb1a..f374ce32 100644
--- a/lib/update-system.nix
+++ b/lib/update-system.nix
@@ -3,7 +3,7 @@ let configPath = "/etc/nixos";
 in {
   update-system = pkgs.writeHaskellScript {
     name = "update-system";
-    bins = [ nixos-rebuild ];
+    bins = [ nixos-rebuild pkgs.nix-output-monitor ];
   } ''
     privatePath = "${configPath}/private"
     canaryPath = privatePath <> "/submodule-is-checked-out"
@@ -12,8 +12,7 @@ in {
         paths <- myNixPath "${configPath}"
         args <- getArgs
         bracket (rm canaryPath) (\() -> exe "/run/wrappers/bin/sudo" "-u" "maralorn" "git" "-C" privatePath "restore" canaryPath) $ \() -> do
-           nixos_rebuild (paths ++ ["build"] ++ remoteBuildParams ++ fmap toString args)
-           rm "result"
-        nixos_rebuild (paths ++ ["switch"] ++ fmap toString args)
+           nix_build (paths ++ buildSystemParams ++ ["--no-out-link"] ++ remoteBuildParams ++ fmap toString args) &!> StdOut |> nom
+        nixos_rebuild (paths ++ ["switch"] ++ fmap toString args) &!> StdOut |> nom
   '';
 }
diff --git a/nixos/machines/hera/configuration.nix b/nixos/machines/hera/configuration.nix
index 7d34c069..7f88d8e0 100644
--- a/nixos/machines/hera/configuration.nix
+++ b/nixos/machines/hera/configuration.nix
@@ -1,8 +1,4 @@
 { config, pkgs, ... }:
-
-# You need pw-files for every configured user in ./secret/pw-useralias for login to work.
-# dropbearkey -t rsa -f /etc/nixos/nixos/machines/<hostname>/secret/boot_rsa
-
 let
   inherit (config.m-0.private) me;
   inherit (import ../../../common/common.nix { inherit pkgs; }) syncthing;
diff --git a/overlays/testing.nix b/overlays/testing.nix
index a02c95a3..4d512e0e 100644
--- a/overlays/testing.nix
+++ b/overlays/testing.nix
@@ -25,7 +25,7 @@ in {
     name = "test-system-config";
     inherit bins;
     inherit imports;
-  } (haskellBody "system" ''nix_build $ ["<nixpkgs/nixos>", "-A", "system"] ++ paths ++ ["-I", [i|nixos-config=#{configDir}/nixos/machines/#{hostname}/configuration.nix|], "-o", [i|result-system-#{hostname}|]] ++ fmap toString args'');
+  } (haskellBody "system" ''nix_build $ buildSystemParams ++ paths ++ ["-I", [i|nixos-config=#{configDir}/nixos/machines/#{hostname}/configuration.nix|], "-o", [i|result-system-#{hostname}|]] ++ fmap toString args'');
 
   test-home-config = self.writeHaskellScript {
     name = "test-home-config";
diff --git a/overlays/writeHaskellScript.nix b/overlays/writeHaskellScript.nix
index 702ce49f..664c9424 100644
--- a/overlays/writeHaskellScript.nix
+++ b/overlays/writeHaskellScript.nix
@@ -55,6 +55,9 @@ self: super: {
          tag name str = ["-I", [i|#{name :: Text}=#{str :: Text}|]] :: [String]
          getNivAssign name = tag name <$> getNivPath path name
 
+      buildSystemParams :: [String]
+      buildSystemParams = ["<nixpkgs/nixos>", "-A", "system"]
+
       remoteBuildParams :: [String]
       remoteBuildParams = ["--builders", "@/etc/nix/machines", "--max-jobs", "1"]