Rental and resale platform, serving customers across North America. The business combines: Rental bookings with date-based availability Purchase (buy outright) options On site by-appointment boutique fittings Group/bridal party coordination Membership tiers with entitlements Insurance add-ons Dynamic pricing by region/season/demand North America shipping with return automation This is NOT a simple Shopify site. Shopify will handle storefront + checkout, but we need a custom backend system to manage: Inventory at SKU-unit level Reservation engine with locking Appointment scheduling Dynamic pricing engine Shipping date automation Lifecycle management (rent → return → inspect → relist) Architecture must be scalable and modular. Required Skills Shopify (Admin API + Webhooks) Node.js (NestJS preferred) OR Python (FastAPI) PostgreSQL (Supabase acceptable) Redis (locking) Background job queues (BullMQ/Celery) REST API design Experience with booking systems or rental platforms preferred Deliverables (Phase 1 MVP) Custom backend API deployed Reservation & availability engine SKU-level inventory tracking Dynamic pricing engine (rule-based) In Person one location appointment booking system with option to multiple in phase 2 Group booking support Shipping automation logic (Shippo/ShipStation) Shopify webhook integration Admin dashboard (basic but functional) Klaviyo event integration Clean, documented, production-ready code required.