5-Day Free Course · Architecture

System Design Built for Interviews and the Real World

Scalability fundamentals, database selection, caching strategies, load balancers, message queues, and end-to-end system design exercises (URL shortener, Twitter, ride-sharing). The course that works for both senior engineering interviews and real architectural decisions.

5 days self-paced
Free forever
Text + external video refs
No signup required
system-design$LB -> [App1, App2, App3]Cache hit: 94.2%$Kafka: 2.1M events/sec$
5
Days
30+
Code Examples
5+
External Videos
$0
Forever Free

No videos. On purpose.

This is a text-first course that links out to the best supporting material on the internet instead of trying to replace it. The goal is to make this the best course on system design you can find — even without producing a single minute of custom video.

Practitioner-tested, not vendor marketing

This course is built by engineers who ship system design systems in production. It reflects how these tools actually behave at scale.

Code you can run, not demos to watch

Every day includes working code examples you can copy, run, and modify right now. Understanding comes through doing.

Links to the canonical sources

Instead of re-explaining existing documentation, this course links to the definitive open-source implementations and the best reference material on system design available.

Completes in 5 one-hour sessions

Each day is designed for about an hour of focused reading plus hands-on work. Do the whole course over a week of lunch breaks. No live classes, no quizzes.

The 5 Days

Each day stands alone. Read them in order for the full picture, or jump straight to the day that answers the question you have today.

01Day One

Scalability Fundamentals

Vertical vs horizontal scaling, stateless services, the CAP theorem and what it actually means in practice, consistency models (strong, eventual, causal), and the mental framework for reasoning about distributed system trade-offs.

CAP theoremhorizontal scalingconsistencytrade-offs
02Day Two

Databases: SQL vs NoSQL vs NewSQL

When to choose PostgreSQL, MongoDB, Cassandra, or Redis — not generic rules but specific scenarios where each wins. Sharding strategies, replication topology, and the database anti-patterns that kill scaling.

PostgreSQLCassandrashardingreplication
03Day Three

Caching, CDNs, and Read Optimization

Cache-aside vs write-through vs write-behind, Redis vs Memcached, CDN edge caching, cache invalidation strategies, the thundering herd problem, and consistent hashing for distributed caches.

RedisCDNcache invalidationconsistent hashing
04Day Four

Message Queues and Async Architecture

Kafka vs RabbitMQ vs SQS, producer/consumer patterns, exactly-once vs at-least-once delivery, fan-out patterns, backpressure, and the event-driven architecture patterns that decouple services at scale.

KafkaRabbitMQexactly-onceevent-driven
05Day Five

Design Exercises: URL Shortener, Twitter, Ride-Sharing

Three end-to-end system design walkthroughs that cover every component from days 1-4. URL shortener (read-heavy, global distribution), Twitter feed (fan-out on write vs read), ride-sharing (geospatial, real-time matching).

URL shortenerTwitter designride-sharingdesign interview

The best external videos on this topic.

Instead of shooting our own videos, we link to the best deep-dives already on YouTube. Watch them alongside the course. All external, all free, all from builders who ship this stuff.

Read the source.

The best way to deepen understanding is to read the canonical open-source implementations. Clone them, trace the code, understand how the concepts in this course get applied in production.

Three kinds of people read this.

Engineers Preparing for Senior Interviews

System design questions are the filter for senior and staff engineering roles. This course covers the components, trade-offs, and design patterns examiners expect you to know.

Architects Designing Production Systems

The patterns in this course aren't just for interviews — they're the actual decisions production teams make. This course gives you the vocabulary and trade-off framework for real architectural discussions.

AI Engineers Scaling Their Systems

AI inference systems, vector databases, and embedding pipelines have the same distributed systems challenges as web applications. This course covers the infrastructure patterns that apply to both.

Want to Go Deeper In Person?

The 2-day in-person Precision AI Academy bootcamp covers system design and AI architecture in depth — hands-on, with practitioners who build AI systems for a living. 5 U.S. cities. $1,490. 40 seats max. June–October 2026 (Thu–Fri).

Reserve Your Seat