diff --git a/nixos/modules/services/x11/desktop-managers/gnome3.nix b/nixos/modules/services/x11/desktop-managers/gnome3.nix
index 5e31247843e..456975015a2 100644
--- a/nixos/modules/services/x11/desktop-managers/gnome3.nix
+++ b/nixos/modules/services/x11/desktop-managers/gnome3.nix
@@ -34,7 +34,7 @@ in {
           export GTK_DATA_PREFIX=${config.system.path}
 
           # find theme engines
-          export GTK_PATH=${config.system.path}/lib/gtk-3.0:{config.system.path}/lib/gtk-2.0
+          export GTK_PATH=${config.system.path}/lib/gtk-3.0:${config.system.path}/lib/gtk-2.0
 
           export XDG_MENU_PREFIX=gnome