rewrite -(unitR V)/V.
have V: valid (W1 \+ W2 \+ Unit) by rewrite unitR validV.
apply: (injectL V); do?[apply: hook_complete_unit | apply: hooks_consistent_unit].
by move=>??????; rewrite dom0.
Defined.

(* Specifications: *)
Lemma hcomp l : hook_complete (mkWorld l).
Definition delegating_server_loop_cond (res : unit) := true.