This article details Zalando's ZEOS system, which enhances inventory management through probabilistic demand forecasting and a simulation-driven replenishment engine. By leveraging an extended (R, s, Q) policy, the system achieved over 22% growth in gross merchandise value by better addressing demand uncertainty.

Flipkart's Promise team optimized the delivery date calculation process for their Search and Browse (S&B) page, reducing latency to 100ms for 100 items while scaling to 10 times the current query per second (QPS). The solution involved caching source and vendor capacities and decoupling their storage to enhance real-time delivery date accuracy and efficiency. These improvements ensure a better user experience without compromising on performance metrics during high demand.