Business: wholesale electronics (phones, tablets, accessories). • Current app: working web beta built on Replit (React UI + basic Node backend + auth/sign‑up). • Goal: turn this into a solid tool my team can use daily, with clean APIs, a real database, and proper inventory / order workflows. What I need built • Review and clean up the existing Replit codebase (frontend + backend). • Design and implement a proper SQL database schema (PostgreSQL or MySQL) for: • Products, SKUs, vendors, customers/organizations • Serialized devices (IMEI/ESN), non‑serialized items • Purchase Orders, Sales Orders, RMAs, Scan Reports, Inventory Reports • Users & roles, settings, audit logs • Implement key workflows: • Purchase Orders: create/edit POs, receive inventory against a PO (this is the ONLY time inventory should be added, unless I open an existing PO). • Inline vendor creation while creating a PO if the vendor doesn’t exist. • Sales Orders: allocate devices/items, update order & payment status. • RMAs: track returns, refund amounts, and returned inventory. • Scan Reports / Process Batches: scan IMEIs/ESNs in bulk and tie them to POs/SOs. • Inventory Reports: monthly/quarterly/custom reports with counts & totals by product/grade/location, plus export (CSV) and optional public link. • Analytics dashboard: revenue, gross profit, margin %, profit per device, top customers, inventory value over time. • Harden the backend: validation, error handling, authentication/authorization (JWT + roles). • (Nice‑to‑have) Package the existing web app as a desktop app for Mac (.dmg) and Windows (.exe) using Electron or similar. Tech stack preference • Node.js + TypeScript • React on the frontend (already in place) • SQL database (PostgreSQL preferred) • Experience with inventory/ERP or e‑commerce back‑office tools is a big plus.