Product architecture

How MarketSquare is put together

Three consoles, one commerce core. Rules and eligibility flow through a shared engine, so what a buyer, seller, and admin see always reflects the same source of truth.

System map

Buyer console

Discovery, wishlist, cart, checkout, order tracking, reviews, direct messaging, maker discovery map.

Seller console

Storefront management, product CRUD, order fulfillment, analytics, subscription tier, buyer messaging.

Admin console

User & seller verification, categories, disputes, reports, moderation, subscription oversight.

Checkout flow

Add to cart

Address & pay

Rules engine

Fulfillment

Notification

Review

Every step emits an event consumed by the rules engine — eligibility, holds, and messaging are decided here.

Rules engine

Order eligibility

if (seller.verified && product.stock >= qty && !buyer.flagged) {
  allow_checkout();
} else if (!seller.verified) {
  hold_for_review("SELLER_UNVERIFIED");
} else if (product.stock < qty) {
  reject("OUT_OF_STOCK");
}

Dispute routing

match dispute.reason:
  "damaged" -> open() -> seller_respond(48h)
  "not_received" -> auto_refund_hold(72h)
  "wrong_item" -> escalate_if_no_response(24h)
  default -> route_to_admin()

Data model (core)

users

id, name, email, role, verified, status

products

id, sellerId, title, price, stock, status

orders

id, buyerId, sellerId, items[], total, status

threads

id, buyerId, sellerId, subject

messages

id, threadId, fromId, toId, text, at

disputes

id, orderId, reason, status

reviews

id, productId, author, rating, text