Headless Shopify E-Commerce OS

Headless Commerce OS is a production-ready headless storefront that puts a modern React application in front of Shopify's battle-tested backend. Shopify handles what it's good at — products, inventory, orders, payments, tax, and compliance. This platform handles everything the customer sees and experiences — with no Liquid, no theme restrictions, no compromises.

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Why I Built It

Shopify themes are a cage. Every store using Dawn, Debut, or any theme-based stack shares the same rendering constraints, animation limits, and data-fetching bottlenecks. Customization hits a wall fast — and that wall is Liquid.

Switching off Shopify entirely means rebuilding inventory management, payments, tax logic, and checkout from scratch. That's months of work and ongoing PCI compliance burden.

✅ Purpose: Full design freedom without abandoning Shopify's ecosystem
🛒 Built for: brands, agencies, and engineering teams that have outgrown theme-based stacks
🛠️ Approach: React Router v7 storefront + NestJS backend + Shopify as the source of truth

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How It Works

Browsing

Customer lands on a server-rendered storefront. First paint is fast — React Router v7 renders on the server, so there's no loading spinner, no layout shift. The product gallery loads with full images, pricing, and variant data already baked in.

Filtering, sorting, and collection browsing all work without full-page reloads.

Product Detail

Customer opens a product. Variants, pricing, compare-at prices, and related products are all resolved in a single backend call. No client-side waterfalls. Add to cart is instant — optimistic UI updates immediately while the mutation runs in the background against Shopify's Cart API.

Cart

Cart state lives in a Redis-backed session tied to an HTTP-only cookie. Returning to the tab, closing the browser, navigating away — cart survives all of it. No localStorage race conditions, no cookie-size limits from stuffing cart data client-side. Quantity updates and item removal are non-blocking.

Checkout

Customer hits "Checkout" and lands on Shopify's hosted checkout — fully PCI-compliant, with native support for Shop Pay, Apple Pay, Google Pay, and every payment method Shopify supports. No custom payment integration required.

Account

Customers can register and log in. Authentication runs through Shopify's Storefront API — credentials and access tokens are managed by Shopify, stored in the session on this platform. Login state persists for 30 days.

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Tech Stack

Layer	Technologies
Storefront	React Router v7, TypeScript, TailwindCSS
Backend	NestJS, REST API
Cart Session	Upstash Redis (HTTP-only cookie sessions)
Commerce	Shopify Storefront API, Shopify Cart API
Auth	Shopify Customer Accounts (Storefront API)
Infrastructure	Fly.io, Docker (auto-scaling, zero-downtime)

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What's Live Today

• 📦 Product catalog — browsing, filtering, collection pages, and product detail
• 🛒 Cart — add, update, remove, persist across sessions and page refreshes
• 💳 Checkout — Shopify-hosted handoff with full payment method support
• 👤 Customer accounts — register, login, logout

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What's Next

• ⚡ Webhook ingestion — real-time order and inventory events with queue and audit logs
• 🔧 Admin API integration — richer product management surface
• 📊 Analytics pipeline — custom event tracking and funnel visibility
• 🧪 A/B testing layer — variant experiments without third-party scripts
• 🔗 ERP integration hooks — sync orders and inventory with external systems
• 🌐 WebGL storefront layer — immersive 3D product experiences powered by Three.js

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Explore the live version of the Headless Commerce OS
👉 ecommerceos-storefront.fly.dev

💡 Built for brands that have outgrown Shopify themes but don't want to abandon the ecosystem — composable commerce with no Liquid, no limits.