🐘 Deep Dive · Database Engineering How Zerodha Scaled to Millions with Just PostgreSQL A no-nonsense technical breakdown of how India's largest stockbroker stretched one open-source database to its absolute limits — and won. 📅 2025 ✍️ play-with-data.blogspot.com ⏱ ~18 min read 🎯 Data Engineers · Backend Engineers · DBAs § 00 · Opening The Counterintuitive Choice When you hear that a platform processes tens of millions of trades per day , serves ~15 million registered users , manages hundreds of billions of rows spanning close to 20 terabytes of financial data, and does all of that while running a 30-person engineering team — the first database that comes to mind is probably not PostgreSQL. You'd expect Cassandra, maybe TiDB, maybe a hybrid of ClickHouse and Kafka with a sprinkling of DynamoDB. You'd expect horizontal auto-scaling, manag...