Learn AI Coding, AI Agents and Software Engineering by Building Real Projects

System Design

System design, low-level and high-level: architecture, code structure, data, scaling, deployment, security and privacy, with interactive figures and interview questions.

15 September

Requirements Become Numbers: Latency, Percentiles, Availability and Estimation

Rajesh Pillai Articles, System Design

Fast” and “reliable” can’t be designed for; p99 under 300 ms and 99.9% of requests succeeding can. Learn percentiles, tail latency, why busy servers get slow, availability nines, SLOs, and back-of-the-envelope estimates.

15 September

The Life of a Request: What Happens When You Open a URL

Rajesh Pillai Articles, System Design

Opening a web page takes a DNS lookup, a TCP handshake, a TLS handshake, and a trip through load balancers, caches, app servers and databases. Follow one real request, measured step by step, and see where the time goes.