Citadel is a network of tiered, interdependant libraries.
Modules relating to the retrieval of information of slices / lists of information. Functions and structures which provide information about the contents of a list, or obtaining specific parts of a sequence go here. In general, if the list is being modified, it belongs in the modify wing, not access.
The Modify branch of citadel handles the manipulation of lists and slices, including the transformation and coercions of such lists.
Functions which are universal to citadel go in prelude, so that they may be included in further submodules without causing cross-depdency between branches of equal order.