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Thoughts on design, code, and everything in between.

'Email Already Taken': Checking Millions of Signups at Scale

Building a robust email uniqueness check that scales to millions of signups. We'll explore Bloom filters, race conditions, email normalization, and why a simple database query isn't enough.

May 4, 2026•5 min read

System DesignDjangoDatabasesBloom FiltersDistributed SystemsPerformanceScaling

How YouTube Stores Downloaded Videos for Offline Playback: A Deep Dive

Ever wondered what actually happens when you hit 'Download' on YouTube? A full system design breakdown of how YouTube encrypts, stores, and serves offline videos on your device.

Apr 10, 2026•5 min read

System DesignYouTubeDRMMobile StorageVideo StreamingEncryptionAndroidiOS

How E-commerce Websites Actually Work: Full System Simulation with Docker

A practical walkthrough of a mini e-commerce architecture using Nginx, Node.js, PostgreSQL, Redis, RabbitMQ, and a worker service with Docker Compose.

Mar 20, 2026•5 min read

DockerE-commerceNext.jsMicroservicesPostgreSQLRedisRabbitMQ