Engineering notes · Knowledge base

Trade-offs, failure modes, and system design.

Deep dives into backend engineering, distributed data, performance, and the lessons behind production architecture decisions.

topicsDistributed SystemsSystem Design ExamplesiGaming Game DesignSystem Design Fundamentals
notes.featured

Featured deep dives

Long-form explanations of the decisions that shape dependable backend systems.

01
Distributed Systems

Why Your New Profile Picture Does Not Immediately Update Everywhere

Changing a profile picture is one write. Making it visible across feeds, search, notifications, caches, and regions is a distributed systems problem.

Aug 18, 2026 19 min read
02
System Design Examples

Engineering High Throughput News Feed Architectures

A news feed looks simple until you have to distribute millions of posts, keep reads fast, handle hot users, and recover cleanly when parts of the system fail. This design explores the decisions that start to matter at scale.

Aug 17, 2026 29 min read
03
Distributed Systems

Exactly-Once Is a Lie or at Least Not the Guarantee You Think It Is

Protecting business invariants with idempotency, transactional outbox patterns, retries, and reconciliation.

Aug 13, 2026 19 min read
notes.archive

All engineering notes

01
Distributed Systems

Why Your New Profile Picture Does Not Immediately Update Everywhere

Changing a profile picture is one write. Making it visible across feeds, search, notifications, caches, and regions is a distributed systems problem.

Aug 18, 2026 19 min read
02
System Design Examples

Engineering High Throughput News Feed Architectures

A news feed looks simple until you have to distribute millions of posts, keep reads fast, handle hot users, and recover cleanly when parts of the system fail. This design explores the decisions that start to matter at scale.

Aug 17, 2026 29 min read
03
Distributed Systems

Exactly-Once Is a Lie or at Least Not the Guarantee You Think It Is

Protecting business invariants with idempotency, transactional outbox patterns, retries, and reconciliation.

Aug 13, 2026 19 min read
04
iGaming Game Design

Designing a Well-Structured Keno Game: Game Engine, Randomness, and Payouts

A deep dive into designing a Keno game, covering game engine design, secure random draws, randomness principles, and payout calculation strategies.

Jan 4, 2026 5 min read
05
System Design Fundamentals

CAP Theorem and Trade-offs Between Consistency and Availability

Understanding the CAP theorem and its impact on distributed system design, including trade offs between consistency, availability, and partition tolerance.

Jan 2, 2026 4 min read
06
System Design Fundamentals

Replication Strategies: Master-Slave and Master-Master

Learn about replication techniques to increase availability and fault tolerance, including master-slave and master-master replication.

Mar 15, 2025 6 min read
07
System Design Fundamentals

Designing Real-World Systems

Step-by-step guide for designing scalable, high-performance systems including requirements gathering, estimations, and component design.

Jan 2, 2026 6 min read
08
System Design Examples

Architecting a Global URL Shortener at Scale

An in-depth look at distributed ID generation, multi-region redirection latency, and event-driven analytics for high-throughput URL shortening services.

Aug 26, 2025 8 min read
09
System Design Fundamentals

Distributed File Storage: S3 and HDFS Concepts

An overview of distributed file storage systems such as Amazon S3 and HDFS, their architecture, and use cases.

Dec 2, 2025 5 min read