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.

You have a primary and three replicas using semi-sync replication. Replica A confirms in 2ms, Replica B in 50ms, Replica C in 300ms. What's the write latency the client experiences?

2ms, it only needs one replica to confirm, Semi-sync waits for the FIRST replica to confirm. Replica A confirms in 2ms, so the write is acknowledged in ~2ms (plus primary write time). Replicas B and C catch up asynchronously.

All three replicas go down simultaneously. The semi-sync timeout is 10 seconds. What happens?

After 10 seconds, the primary falls back to async mode and continues accepting writes without replica confirmation, MySQL semi-sync has a timeout (rpl_semi_sync_master_timeout). If no replica confirms within that window, the primary degrades to async mode. Writes continue, but now data only exists on the primary. You lose the durability guarantee until replicas recover.

What is the difference between AFTER_COMMIT and AFTER_SYNC modes in MySQL semi-sync?

AFTER_SYNC waits for replica ACK before committing to the storage engine, preventing phantom reads after a crash, In AFTER_COMMIT mode, the primary commits to the storage engine first, then waits for replica ACK. If the primary crashes after commit but before ACK, the replica may not have the data, yet local clients already saw it. AFTER_SYNC (loss-less mode) waits for replica ACK before committing, eliminating this window.

Semi-Synchronous Replication

Name: System Design Masterclass
Availability: InStock

in Data Replication Distribution

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

One-time payment. Lifetime access. No subscription.

Global

$19.99$7.99/lifetime

One-time payment via PayPal

Get Lifetime Access

Foundation lessons free, try before you buy

Founders price, locked for the first 10,000 customers

India Special

India

₹999₹499/lifetime

One-time via UPI, cards, or net banking

Get Lifetime Access

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

Completion certificates per level

Lifetime access, all future content included

The first 5 Foundation lessons are free, no payment needed. Try them now