Design a Price Tracker
Medium · System Design · about 45 minutes
Asked at Amazon, Google, eBay, Shopify, Instacart, Walmart Global Tech, Wayfair, Etsy, Shopee, Flipkart, Zalando.
Design a price tracking service like CamelCamelCamel. It tracks ~500M products on large e-commerce sites, shows each product's price history chart, and lets ~10M users set ~50M alerts ("notify me when this drops below $X"). Products people care about should be checked at least hourly while respecting retailers' rate limits.