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.

A count-based window is configured with size 1000 on a key that stops producing events after 300 records. What happens?

The 300 events sit in state forever and the window never fires, A pure count trigger waits indefinitely for the next event. There is no timeout. The partial window holds 300 events in state and never emits. This is why a composite trigger with a time fallback is mandatory in production.

What is the correct way to handle the stale window problem?

Use a composite trigger that fires on count OR processing time, whichever comes first, wrapped in PurgingTrigger.of() to clear state after firing, CountTrigger.of(1000) combined with ProcessingTimeTrigger that fires after 30 seconds, wrapped in PurgingTrigger.of(), gives full batches at peak and bounded latency at trough. Without PurgingTrigger, state persists across fires and you double-count events.

A count window of size 1000 runs at 10,000 events/second during peak and 5 events/second during off-peak. What are the effective latencies?

100 ms during peak, 200 seconds during off-peak, At 10,000 events/second, 1000 events arrive in 100 ms. At 5 events/second, 1000 events take 200 seconds. The same count window behaves like two completely different systems in different traffic regimes, which is why the time fallback is mandatory.

Count-Based Windows

Name: System Design Masterclass
Availability: InStock

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