ykonai via Guix-patches via <guix-patches@gnu.org> skribis:

> * gnu/packages/lisp-xyz.scm (sbcl-cl-gtk4, cl-gtk4): New variables.
> [...]
> +      ;; propagate because it at least requires the typelib files at runtime
> +      (propagated-inputs (list gtk))
> +      (inputs
> +       (list gobject-introspection
> +             sbcl-cl-glib
> +             sbcl-cl-gobject-introspection-wrapper))
> [...]

Hi.
Instead of propagating Gtk, have your checked if having the
GI_TYPELIB_PATH environment variable set at runtime could be enough to
make things work?