Full course outline

Syllabus

19 steps across six phases, from internet basics to a repeatable design framework, practiced on three systems: Shorty, a rate limiter, and a chat service. Click any lesson to jump straight to it.

Foundations

1What Is System Design?The gap between an idea and a technical blueprint, and how this differs from frameworks like TOGAF.~5 min 2How Computers Talk: Networks, DNS, and HTTPIP addresses, DNS, TCP vs UDP, and HTTP/HTTPS — the plumbing every request travels through.~7 min

Scoping the Problem

3Understand the RequirementsFunctional vs non-functional requirements and constraints, using Shorty as the running example.~6 min 4Estimate Scale and CapacityBack-of-envelope math for requests per second, peak traffic, and storage growth.~7 min

Architecture & Communication

5Design the High-Level ArchitectureLoad balancers, application servers, reverse proxies, and monolith vs microservices.~7 min 6Design APIs and CommunicationEndpoints, status codes, and when to go asynchronous with a message queue.~7 min

Data

7Design the Data Model and StorageRecords, primary keys, and indexes — what to store and how to find it fast.~6 min 8Choosing SQL or NoSQLRelational, document, and key-value stores, and how to pick based on access patterns.~7 min 9Scaling Data: Replication and ShardingSpreading data across machines safely as it outgrows a single database.~7 min 10Consistency and the CAP TheoremWhat to do when replicas disagree during a network partition.~8 min

Non-Functional Engineering

11Caching and CDNsSpeeding up reads with caches and edge delivery, and the invalidation problem that comes with it.~6 min 12Load Balancing and Horizontal ScalingAdding capacity by adding machines, and why stateless servers make that possible.~7 min 13Reliability, Redundancy, and FailoverDesigning for failure with redundancy, automatic failover, and SLA math.~7 min 14Security FundamentalsAuthentication vs authorization, encryption in transit and at rest, and rate limiting.~7 min 15Observability: Logs, Metrics, TracesLogs, metrics, and traces — how you actually see what a live system is doing.~6 min

Synthesis

16Identify Trade-offs and Improve the DesignNaming the trade-offs behind every design choice instead of calling one option simply "best."~6 min

Practice: Case Studies

17Case Study: Design a Rate LimiterApplying the full framework quickly to a smaller, self-contained system.~8 min 18Case Study: Design a Chat SystemA second walkthrough for a very different shape of problem: real-time, two-way communication.~8 min

Reference

19Glossary and Cheat SheetEvery key term from the course, grouped by topic, to revisit any time.Browse anytime

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