🧱 Marketplace Management and Inventory System — Architecture & Development Plan

📌 Overview

This project transitions a frontend built on a Shopify template into a fully custom, multi-tenant Marketplace Management and Inventory System, startup name will be ShopStack.

🎯 Goals

• Own the data layer
• Control business logic
• Enable multi-store support
• Build a scalable DevOps-ready system

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API STRUCTURE (FOR DOCS)

🔐 Auth Module

POST   /api/auth/register
POST   /api/auth/login
POST   /api/auth/logout
GET    /api/auth/me
POST   /api/auth/refresh

👤 User Module

GET    /api/users/me
PATCH  /api/users/me
DELETE /api/users/me

GET    /api/users/:id        (admin)
PATCH  /api/users/:id       (admin)
DELETE /api/users/:id       (admin)

🛠️ Admin Module

GET    /api/admin/dashboard

GET    /api/admin/users
GET    /api/admin/users/:id

GET    /api/admin/stores
GET    /api/admin/products

PATCH  /api/admin/products/:id   (approve/reject)
DELETE /api/admin/products/:id

GET    /api/admin/analytics/overview
GET    /api/admin/logs

🏪 Store Module (important)

POST   /api/stores
GET    /api/stores
GET    /api/stores/:id
PATCH  /api/stores/:id
DELETE /api/stores/:id

Store Members (optional but powerful)
GET    /api/stores/:id/members
POST   /api/stores/:id/members
PATCH  /api/stores/:id/members/:userId
DELETE /api/stores/:id/members/:userId

📦 Product Module (Scoped to Store)

POST   /api/stores/:storeId/products
GET    /api/stores/:storeId/products
GET    /api/products/:id
PATCH  /api/products/:id
DELETE /api/products/:id

GET    /api/products/reorder-recommendations

🗂️ Category Module

POST   /api/categories
GET    /api/categories
GET    /api/categories/:id
PATCH  /api/categories/:id
DELETE /api/categories/:id

📊 Inventory Module (NEW)

GET    /api/stores/:storeId/inventory
PATCH  /api/stores/:storeId/inventory/:productId

POST   /api/inventory/adjust
GET    /api/inventory/history

🛒 Cart Module (FIXED STRUCTURE)

GET    /api/cart
POST   /api/cart
PATCH  /api/cart/:itemId
DELETE /api/cart/:itemId

👉 Remove:
PATCH /api/orders
DELETE /api/orders
POST  /api/orders/cart

🧾 Order Module

POST   /api/orders/checkout
GET    /api/orders
GET    /api/orders/:id
GET    /api/orders/my

PATCH  /api/orders/:id/status

GET    /api/orders/product/:productId/history
GET    /api/orders/sales-trends

🧾 Invoice Module

GET    /api/invoice/:orderId
📊 Analytics Module (FIX PATH)
GET    /api/analytics/admin-inventory
GET    /api/analytics/top-products
GET    /api/analytics/sales

🌐 Public Storefront (NEW 🔥)

GET /api/public/stores
GET /api/public/stores/:id

GET /api/public/products
GET /api/public/products/:id

⭐ Optional (Advanced Features)

POST /api/products/:id/reviews
GET  /api/products/:id/reviews

GET  /api/search/products?q=shoes

🧱 FINAL CLEANUP NOTES

🚨 Rename / Fix
❌ /api/api/analytics/... → /api/analytics/...
❌ cart inside orders → separate module
❌ /api/dashboard → /api/admin/dashboard

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🗺️ Development Phases

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Phase 1 — 👷‍♂️ Infrastructure & Backend Core

🎯 Goal

Establish backend as the source of truth

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🧩 Database Schema (Prisma)

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🔄 Sequence Flow

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🧱 Architecture Flow

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Phase 2 — ⛓️‍💥 Frontend Decoupling

🎯 Goal

Replace Shopify dependencies with internal API

🔄 Data Fetching Flow

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🔧 Key Changes

• Replace use-shopify → custom hooks
• Use React Query
• Replace environment variable:

NEXT_PUBLIC_API_URL=http://localhost:3000

Phase 3 — 🤝 Multi-Tenancy & Store System

🎯 Goal

Support multiple independent stores

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🧩 Store Routing

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🔄 Auth + Store Flow

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Phase 4 — 👨‍💻 DevOps & Scalability

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🧩 Migration Strategy in the future

• Abstract service layer
• Replace ORM without breaking API:
  • Prisma → Drizzle / Supabase

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🧱 Monorepo Architecture (Turborepo)

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📁 Suggested Structure

apps/
  frontend/   # Next.js app
  backend/    # NestJS API

packages/
  ui/         # shared components
  types/      # shared types/interfaces
  config/     # eslint, tsconfig, etc.

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🔁 System-Wide Data Flow

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🆚 Shopify vs Custom System

Feature	Shopify Template	Custom System
Database	Shopify-managed	SQL (Prisma)
API	Shopify GraphQL	NestJS API
Control	Limited	Full
Auth	External	Internal
Multi-tenancy	Built-in	Custom

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🧠 Design Principles

• Decoupled Architecture
• Interface Stability
• Scalability-first mindset
• ORM abstraction

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🚀 Future Enhancements

• Role-based access control
• Order management system
• Analytics dashboard
• Redis caching
• Event-driven architecture (webhooks)

🛍️ Missing marketplace-level features (future)

Not required now, but needed in future:

• Order per store split (important for multi-vendor)
• Payment table
• Shipping info

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