Frontend System Design Interview: State, Cache & Real Systems

What you will learn

• Core Web Vitals, field-to-lab diagnosis, budgets, browser architecture, and viewport performance
• Product systems: feeds, commerce, chat, travel, and discovery
• Media, real-time, offline-first, design systems, and accessibility
• Twitter/X, Instagram, Facebook, and a reusable social-feed architecture
• Industry patterns from Pinterest, Airbnb, Vercel, Netflix, JioHotstar, Rippling, Myntra, Flipkart, Zepto, Google, and AWS

How it works

A design that looks fine on a whiteboard, then the failure mode (stale cache, waterfall, split-brain tab) and the cut that fixes it.

More courses

• Jobs, linked to lessons — Browse jobs where every requirement links to the chapter that teaches it. See how ready you are, how long the gap takes to close, and which listings look stale.
• Match a job post to courses — Paste a job post. Each skill is matched to a track here and put in learning order, foundations first.
• React from open source with patterns — Patterns extracted from Material UI, Radix, React Aria, React Hook Form, Redux Toolkit, TanStack, and Next.js — not slides about hooks.
• Database in depth — How a query becomes work. Indexes, isolation, locks, and the plans that explain why a page is slow — not an ORM tour.
• System Design — Eight interview case studies, from a flash sale and Tatkal to a live final and a chat model, plus JWT in separate chapters.
• Microservices — Microservice patterns one diagram at a time: how to split a monolith, how services talk, and how data stays consistent without distributed transactions.
• Kafka — A beginner-to-senior path through event logs, reliable delivery, production operations, and disaster recovery.
• CSS in depth — See the box, then the page. Visual chapters from the box model through Flexbox surprises, Grid, selectors, and units, then backgrounds, shapes, and visual effects, each with a playground.
• Accessibility — HTML labs first, then a full pass of WAI-ARIA 1.3: naming, every state, widget and structure roles, live regions, ariaNotify, and relationships.
• Docker — What an image is, why layers cache, and how containers find each other on a network.
• Redis — Fifteen Redis patterns, one picture each: cache, session, lock, counter, rate limiter, queue, and when Redis is the wrong tool.