diff --git a/machines/common/nogui/default.nix b/machines/common/nogui/default.nix
index d168dde..2c42961 100644
--- a/machines/common/nogui/default.nix
+++ b/machines/common/nogui/default.nix
@@ -44,6 +44,7 @@
 
   nix = {
     gc.automatic = true;
+    optimise.automatic = true;
     package = pkgs.nixVersions.stable;
     settings = {
       trusted-users = [
@@ -55,7 +56,6 @@
         "flakes"
         "nix-command"
       ];
-      optimise = true;
       warn-dirty = false;
       substituters = [ "https://jolheiser.cachix.org" ];
       trusted-public-keys = [ "jolheiser.cachix.org-1:fiKkfTuHFqDK5ZOVxcqb4InUkKsrTvtMLISid7XvuVg=" ];