A multi-tenant automotive service SaaS for garages, garage staff, suppliers, supplier staff, customers, and platform admins. I owned the full-stack implementation across tenant-scoped data models, server-side authorization, RBAC flows, job cards, inspections, inventory, supplier marketplace orders, invoicing, payments, reporting, and dashboards. Garage-side records are scoped by garageId, supplier-side records by supplierOrgId, and server actions derive tenant context from the authenticated user instead of trusting client input.