Is this a video course?

No. This is an interactive, slide-based learning platform. Each lesson has rich text, animated diagrams, live code editors, and quizzes. You learn by reading, interacting, and doing, not by watching videos passively.

How long do I have access?

Forever. Both pricing tiers are one-time payments with lifetime access. This includes all current 766 lessons and any future content we add.

What level of experience do I need?

None. We start from absolute basics like 'What is latency?' and build up to distributed consensus protocols. The Foundation level assumes zero prior knowledge of system design.

How much does the system design course cost?

7.99 US dollars for lifetime access globally, or 499 Indian rupees for lifetime access in India. One-time payment, no subscription, no hidden fees. 11 lessons are free with no signup required.

What technologies are covered?

Everything from DNS and load balancers to Kubernetes, Kafka, distributed databases, consensus protocols, stream processing, security architecture, and observability. We cover principles and real-world implementations used at Netflix, Google, Amazon, Uber, Stripe, and more.

Is this useful for system design interview preparation?

Yes. The lessons are structured around the exact topics asked in system design interviews at FAANG and top-tier companies. Interactive diagrams help you practice whiteboard-style explanations. Covers everything from URL shortener design to distributed payment systems.

How is this different from ByteByteGo or Educative?

766 interactive lessons (4x more than most competitors), 16 different diagram types that build step by step, real production examples from Netflix, Google, Amazon, Uber, and Stripe, and lifetime access for a one-time payment of $7.99 instead of annual subscriptions costing 100 to 200 dollars per year.

Adding loading='lazy' to the hero image at the top of the page will:

Delay Largest Contentful Paint because the browser waits for the viewport check before fetching, The browser only begins fetching lazy images when they approach the viewport. For a hero image that is already visible, this adds an unnecessary delay. The browser could have started the fetch during HTML parsing but instead waits for IntersectionObserver. LCP suffers.

Why is the YouTube facade pattern more effective than adding loading='lazy' to a YouTube iframe?

A facade loads only a thumbnail (few KB) instead of the full player (500KB+), and the player code only loads if the user clicks play, Even with loading='lazy', the iframe still loads the full YouTube player (500KB+) when it enters the viewport. A facade shows a static thumbnail until the user clicks play, meaning users who never play the video never download the player code at all.

On a page with 40 product images (60KB each), lazy loading all but the 8 above-fold images saves approximately how much initial bandwidth?

1.9MB, 40 images at 60KB = 2.4MB total. 8 above-fold images load immediately: 480KB. The remaining 32 images (1.92MB) are deferred until scrolled into view. Initial payload drops from 2.4MB to 480KB.

Lazy Loading

Name: System Design Masterclass
Availability: InStock

in Web Content Delivery

This lesson is part of the full System Design Masterclass. Unlock it along with 765 other lessons for a one-time payment.

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$19.99$7.99/lifetime

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Foundation lessons free, try before you buy

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India Special

India

₹999₹499/lifetime

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Foundation lessons free, try before you buy

Founders price, locked for the first 10,000 customers

“The interactive diagrams alone are worth way more than the price.”

Anish K., Senior Engineer at a Bengaluru startup

All 766 interactive lessons

Step-by-step animated diagrams

Live code editors with real execution

Quizzes with instant feedback

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Lifetime access, all future content included

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