{ stdenv, fetchFromGitHub, gtk3, pythonPackages, intltool, gnome3,
  pango, gobjectIntrospection, wrapGAppsHook,
# Optional packages:
 enableOSM ? true, osm-gps-map,
 enableGtkSpell ? true, gtkspell
 }:


Gives:

error: anonymous function at /home/user/NixPkgs/kp340/nixpkgs/pkgs/applications/misc/gramps/default.nix:1:1 called without required argument 'gtkspell', at /home/user/NixPkgs/kp340/nixpkgs/lib/customisation.nix:69:12