Binary heaps are mutable collections that can contain any Scheme object provided there exists a total ordering on the objects expressed by a SRFI 128 comparator. They are intended to be a thin veneer over vectors. Binary heaps are disjoint from other types of Scheme objects.
See Pileup, a Common Lisp implementation of heaps. This SRFI will not support the special threading requirements, and of course a Great Renaming will be performed.