Understand the Systems You Build

Every system is built from the same 7 building blocks.

Whether you're a junior engineer, a vibe coder, or building with AI for the first time. Learn the universal framework that turns any system from a mystery into a blueprint.

Learn the Framework Try the Challenges

Free and open source. No account required.

AI writes code faster than ever.

But do you understand what it built?

Junior Engineer

You write features but can't explain the architecture. When someone asks "why did you use a queue here?" you don't have a clear answer.

Vibe Coder

You ship fast but don't know why it breaks. AI wrote the code, but when it falls over in production, you're stuck.

Career Changer

You can code but haven't worked on production systems. You know syntax, but not how real applications are put together.

The 7 Building Blocks

Instagram, Netflix, Uber, Gmail. They all use the same pieces.

Task Blocks

Service Service
Worker Worker

Storage Blocks

Key-Value Store Key-Value Store
File Store File Store
Queue Queue
Relational Database Relational DB
Vector Database Vector DB

Free and open source. 7 articles. Interactive challenges.

Explore the Framework

How It Works

1

Read the articles

Learn what each building block does and when to use it. Each article focuses on one block with real-world examples.

2

Try the challenges

Design Instagram, Netflix, and Uber yourself. Pick the building blocks, connect them, and see how your design compares.

3

Go deeper

Interactive labs, AI-graded assessments, and multi-part design challenges in the full course. Get feedback on your thinking.

Taught at UC Berkeley

This framework was developed over 10 years of teaching full-stack web architecture to graduate students. The same patterns, now available to everyone.

Kay Ashaolu
Kay Ashaolu

Continuing Lecturer at UC Berkeley School of Information. Engineering Manager with 15+ years experience at Pinterest, AncestryDNA, and Morgan Stanley. Teaching engineers to think in systems.

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What Students Say

"The way Kay integrates AI tools into his teaching gave me the confidence I once had in software development."

Student

"[Professor Kay] has this incredible ability to make any complex technical challenge seem very simple."

Former Student

"Kay has that rare gift of not only demonstrating deep expertise in his field, but also being able to communicate his insights in a way that is understandable to wide audiences."

Former Colleague

Prefer email? 7 days, 7 building blocks.

One building block per day, delivered to your inbox. Short, practical, with real examples from systems you already use.

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Ready for the Full Experience?

The free framework gives you the concepts. The full course gives you feedback, practice, and depth.

Free Framework

$0

  • 7 building block articles
  • 3 interactive challenges
  • Email course option
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Course I

$99 $149

  • 12 video lessons
  • 2 interactive Python labs
  • AI-graded assessments
  • 3-part design challenge
  • Cohort learning
Explore Course I

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Frequently Asked Questions

What are the 7 building blocks?
Service, Worker, Key-Value Store, File Store, Queue, Relational Database, and Vector Database. These are the universal components that make up every software system, from Instagram to Netflix to Uber. Learn them once, and you can understand any architecture.
Is this interview prep?
No. This is about understanding how systems actually work. That understanding helps in interviews, but it also helps when you're building, debugging, or directing AI to write code. The goal is comprehension, not memorization.
Do I need programming experience?
You should be comfortable reading code, but the framework itself is technology-agnostic. The 7 building blocks are concepts, not code. If you can understand "photos need to be stored somewhere" and "users need to log in," you can learn this framework.
What's free vs paid?
The 7 building block articles and interactive challenges are free. The full course ($99) adds 12 video lessons, interactive Python labs, AI-graded assessments, a 3-part design challenge with feedback, and cohort learning. The 4-course bundle is $399.
How does this help me work with AI?
AI tools are great at writing code but need human guidance for architectural decisions. When you understand building blocks, you can tell AI exactly what to build: "Service for the API, Relational Database for users, Key-Value Store for sessions." Instead of "build me an app" and hoping for the best.
How long does Course I take?
Course I is designed as a 10-week experience at 1-2 hours per week. It's fully self-paced, so you can move faster if you want. All content stays accessible forever.

Start with the building blocks.

Every system you use, every architecture you'll build, every AI-generated codebase you'll review. It all comes back to 7 building blocks.

Learn the Framework Try the Challenges