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What I'm Building: Course 2 Progress Update #1

Hey there,

I want to share why I'm building these courses and what happened this week.

The "Why" Behind Systems Thinking in the AI Era

Two realizations drove me to create this course series:

1. The career transformation gap. When I was a junior engineer, "design Instagram" paralyzed me. I'd freeze up, unsure where to start. Then I noticed senior engineers didn't have special knowledge about Instagram's codebase - they had a mental framework. They saw systems as compositions of just 7 building blocks (Service, Worker, Queue, Key-Value Store, File Store, Relational Database, Vector Database) + 3 external entities (User, External Service, Time). Once I learned this framework, I could approach any system design problem systematically.

2. AI-safe skills. AI can implement code. It can write functions, classes, and tests. What AI cannot replicate is the architectural judgment that comes from pattern recognition and trade-off analysis. Knowing which building block to use, why this caching strategy over that one, and how requirements shape architecture - these are human-only decisions that keep engineers valuable.

The goal: transform junior engineers from "how do I implement this?" to "what are the requirements and trade-offs?"

NEW: Try the Interactive Building Blocks Challenge

Want to test your system design intuition right now? I just launched an interactive challenge where you design Instagram, Netflix, and Uber using the 7 building blocks.

Here's how it works:

It takes about 5 minutes and shows you exactly where your mental model is strong and where the course can help.

Try the challenge now - no signup required to start.

Course 1 Recap

Course I teaches the foundation: all 7 building blocks and 3 external entities with hands-on Python labs where you experience why certain patterns work. There's a 12-lesson video course, 2 interactive discovery labs (Queue+Worker and Time+Worker), a comprehensive assessment, and a 3-part system design challenge where you evolve a social recipe platform from MVP to viral growth to monetization.

It's the prerequisite for everything else because you can't analyze content systems, real-time systems, or business systems without this shared vocabulary.

Special for newsletter readers: Use code SPECIAL200 to get Course I for $99 (normally $299). Grab it here.

Course 2: What's Coming

Course II dives into content systems - the read-heavy platforms that serve millions of users. Think Instagram feeds, Netflix catalogs, YouTube recommendations.

Here's the structure:

5 case studies with introduction + design analysis for each:

2 discovery labs:

3-part challenge: Design a news aggregation platform

Course II is $99 during early bird. Once I finish recording and launch, it goes to $299. Lock in early bird pricing now.

This Week's Progress

Created all 22 course pages:

Next: Start recording video lessons and configuring AI-Powered grading for course 2

More on our AI-Powered Grading approach

I'm configuring the LLM to grade assessments and system design challenges for course 2, the same functionality that is in Course 1. The approach is system prompting with detailed rubrics - not fine-tuning. The AI reviews each submission against specific criteria (did they justify their building block selection? did they address the external entities? did they explain trade-offs?). Students get detailed feedback explaining what worked and what to improve.

There's also a human review option if you want to discuss your grade.

Get Both Courses for $198 (Save $400)

Right now you can lock in both courses at the lowest prices:

That's $198 total instead of $598 once both are at full price.

Questions?

Just reply to this email. I read every response.

-- Kay

P.S. If someone forwarded this to you, sign up for the mini course to get these updates directly.