diff --git a/nixos/modules/services/x11/desktop-managers/gnome3.nix b/nixos/modules/services/x11/desktop-managers/gnome3.nix
index f27d8886187e..a8052649ae01 100644
--- a/nixos/modules/services/x11/desktop-managers/gnome3.nix
+++ b/nixos/modules/services/x11/desktop-managers/gnome3.nix
@@ -143,6 +143,7 @@ in {
       fi
     '';
 
+    environment.variables.GNOME_SESSION_DEBUG = optionalString cfg.debug "1";
 
     # Override default mimeapps
     environment.variables.XDG_DATA_DIRS = [ "${mimeAppsList}/share" ];