HR-to-payroll integration must solve time, structure, vocabulary, and destination simultaneously. Time means reconciling effective-dated source records with target pay-period semantics, including retros, future-dated changes, YTDs, and historical retrieval. Structure means flattening nested HR object graphs into flat payroll templates. Vocabulary means translating source enumerations to target value lists per client, per country, per table. Destination means reverse-engineering source extraction from the receiver’s template. Generic tools handle one or two dimensions and produce wrong numbers when the others are ignored.
