9 curated sequences — each path connects systems that teach the same underlying patterns, so you build intuition, not just isolated knowledge.
How read-dominated systems use caches, CDNs, and precomputation to make the hot path effectively free.
The five systems that appear most in senior engineering loops — from a warm-up URL shortener to a full fan-out social feed and a payment system that cannot double-charge.
Queues, fan-out, retries, webhooks: when and why to decouple work from the request path.
Persistent connections, presence, pub/sub fanout, geo-indexed dispatch: designs where seconds matter.
From a distributed cache to an object store to a global event log — how data is stored, replicated, and retrieved at scale across fundamentally different storage engines.
How users find things: from the instant suggestions in a search box to the inverted index behind full-text search, location-based ranking, and the crawler that feeds it all.
Systems where failure is not an option: rate limiters that protect your service, schedulers that never drop a job, and payment flows that cannot charge twice.
The systems underneath the systems: unique ID generation, distributed object storage, event streaming, and a federated social protocol — the plumbing the internet runs on.
The architectures behind Netflix, TikTok, Airbnb, and the stock exchange — each one a masterclass in a different hard problem at scale.
Not sure where to start?
If you have an interview coming up, start with the FAANG fast track. If you want deep understanding, start with Database Deep Dive.