Own canonical data modeling: define stable, source-agnostic entities and relationships that represent the business domain (e.g., payroll constructs such as Gross Pay, Net Pay, Regular Pay, Bonus, Termination) independent of any single vendor's data shape. Design config-driven architecture: ensure new source systems, clients, or field variations are onboarded through configuration and mapping rules rather than one-off code changes or schema forks. Enforce correctness and reconciliation disciplin…