Two-Sided Marketplace Platform

Summary

A two-sided marketplace architecture serving buyers, sellers, listings, transactions, search, and notifications from a shared infrastructure, where multiple independent domains must coordinate without tight coupling. Event sourcing captures every state transition; the saga pattern orchestrates multi-step transactions (create order, reserve inventory, charge payment, notify seller) with compensating transactions for partial failures. Kafka decouples domain event publication from consumption; RabbitMQ handles notification fanout; Elasticsearch serves listing search; Redis caches listing display and session state.

Problem Statement

Marketplace platforms combine multiple distinct operational domains: catalog/listings, search/discovery, order/transaction, payments, notifications, seller operations: that must stay loosely coupled but operationally coordinated. A listing update must propagate to search without blocking the write path. A payment failure must trigger compensating inventory release without requiring synchronous rollback across services. A trending listing must serve thousands of concurrent reads without overloading the transactional store. The architecture must handle unpredictable traffic spikes (sale events, viral listings) while maintaining transaction consistency for financial operations.