DeltaLedger is a manufacturing decision-support platform that quantifies the financial exposure of engineering changes before approval. It reconciles BOM revisions against open purchase orders, inventory, work in process, supplier terms, and effectivity dates, then produces a traceable decision record with known, estimated, and unresolved exposure clearly separated. DeltaLedger complements existing ERP and PLM systems through guided spreadsheet imports, deterministic calculations, mitigation workflows, executive reporting, and an evidence-constrained AI analyst.