Technique for deleting code completely. Model classes/methods as a graph with usage edges; traverse it breadth-first from a top-level entry point (endpoint or class), listing in a notebook every dependency (classes, methods, i18n keys, CSS classes used as JS event hooks, CSS rules). Cross nodes out as they are removed, append newly discovered dependencies at the bottom, and repeat until nothing is left. Helps avoid dangling references that otherwise resurface later.