Managing Multi-Vendor Marketplaces Architecture

A marketplace is not just a store; it is a platform. The complexity shifts from 'selling products' to 'managing a distributed network of sellers.'

The Multi-Tenant Data Problem

The biggest mistake in marketplace architecture is using a single shared table with a `vendor_id` column. At scale, one 'Power Seller' with a million products can slow down the queries for every other vendor on the platform.

The solution is **Cell-Based Architecture**. We group vendors into isolated 'cells' (separate database shards). This ensures that a traffic spike for one vendor doesn't crash the entire marketplace.

Automating the Payout Engine

Manually calculating commissions for 1,000 vendors is impossible. We implement an **Asynchronous Payout Pipeline**. When an order is marked 'Delivered,' an event is fired to a queue (SQS/Kafka), which calculates the commission and triggers a payout via a provider like Stripe Connect.