The System Design Newsletter

The System Design Newsletter

How Stock Exchange Works
#101: Stock Exchange System Design - Part 1
Nov 18, 2025 • Neo Kim
How Stripe Prevents Double Payment Using Idempotent API
#45: A Simple Introduction to Idempotent API (4 minutes)
May 9, 2024 • Neo Kim
How Uber Finds Nearby Drivers at 1 Million Requests per Second
#31: And How Proximity Service Works Explained Like You’re Twelve (5 minutes)
Jan 4, 2024 • Neo Kim
8 Reasons Why WhatsApp Was Able to Support 50 Billion Messages a Day With Only 32 Engineers
#1: Learn More - Awesome WhatsApp Engineering (6 minutes)
Aug 27, 2023 • Neo Kim
I struggled with system design until I learned these 114 concepts
#120: Part 1 - scalability, availability, reliability, and 35 others.
Feb 7 • Neo Kim
MCP - A Deep Dive
#110: Understanding Model Context Protocol
Dec 26, 2025 • Eric Roby and Neo Kim
System Design Playbook 🔥
Download My Playbook for Free
May 23, 2025 • Neo Kim
How PayPal Was Able to Support a Billion Transactions per Day With Only 8 Virtual Machines
#30: Learn More - Awesome PayPal Engineering (4 minutes)
Dec 26, 2023 • Neo Kim
How Kafka Works
#91: Learn Everything About Apache Kafka’s Architecture, Including Brokers, KRaft, Topic Partitions, Tiered Storage, Exactly Once, Kafka Connect, Kafka…
Sep 25, 2025 • Neo Kim and Stanislav Kozlovski
How Google Ads Was Able to Support 4.77 Billion Users With a SQL Database 🔥
#60: Break Into Google Spanner Architecture (5 Minutes)
Nov 9, 2024 • Neo Kim
The Entire Computer Science Stack, Explained In 51 Images
#115: Fifty-one visuals that show how everything connects in computer science from the ground up
Jan 24 • Neo Kim and Dr. Ashish Bamania
How Shopify Handled 30TB per Minute With a Modular Monolith Architecture 🔥
#63: Break Into Modular Monolith Architecture (3 Minutes)
Dec 22, 2024 • Neo Kim
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