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IntermediateSystem DesignHLDLLD

System Design Interview

HLD and LLD for interviews — scalability, databases, caching, queues, and real case studies, diagram-first.

4.9 6 sections 24 lessons ~3h read
System Design Interview
₹399₹249984% off
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  • 3 free preview lessons
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  • Interview-focused, visual-first

What you'll learn

A repeatable six-step interview framework and back-of-the-envelope estimation (QPS, storage, latency)
Scaling fundamentals: vertical vs horizontal, load balancing, stateless services, and CDNs
Data at scale: SQL vs NoSQL, replication, sharding, and choosing a consistency model with CAP
Caching done right — cache-aside, invalidation, stampedes — plus message queues and idempotency
Four worked case studies: URL shortener, news feed (fan-out), rate limiter, and a full ride-sharing design
Production polish: availability & redundancy, observability (metrics/logs/traces), and trade-off reasoning

About this course

Master the system design interview with a visual, framework-driven approach. Start with a repeatable six-step framework and back-of-the-envelope estimation, then build up every core component: horizontal scaling, load balancers, statelessness, and CDNs; SQL vs NoSQL, replication, sharding, and the CAP trade-off; caching patterns, message queues, and idempotency. Apply it all in four worked case studies — URL shortener, news feed, rate limiter, and a full ride-sharing walkthrough — and finish with the reliability, observability, and trade-off reasoning that separate strong candidates. Every concept is taught with diagrams and the exact things to say out loud in the room.

Curriculum

6 sections · 24 lessons · ~3h

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