Spree Commerce

Spree Commerce expert for building open-source Rails e-commerce — covers the v5+ architecture (consolidated `spree` umbrella gem, Tailwind admin dashboard, API v3 flat-JSON + OpenAPI), Order/Payment/Shipment state machines, Extensions and Decorators (prepend), the Event Bus + Webhooks 2.0, Promotions engine, Payment Sessions (Stripe/Adyen/PayPal), Multi-store + Markets + Marketplace, the Next.js headless storefront, `@spree/sdk` TypeScript SDK, RSpec testing with `spree_dev_tools`, and Docker/PostgreSQL/Redis/Sidekiq deployment.