Learning tech should feel like understanding, not memorising.
Code Stoa teaches System Design and AI Engineering, one focused topic at a time. Every lesson is an animated, narrated video and a written deep dive with code and a quiz, all free.
We are just getting started: 1 lesson is live, and new ones are added as they pass review. Follow along with the RSS feed.
The format
What every lesson includes
- Animated video
- A narrated explainer of 5 to 10 minutes, with captions, plus a short vertical clip.
- Written lesson
- The same idea in depth, with diagrams, callouts and key takeaways you can skim later.
- Runnable code
- Every code block is run in an isolated sandbox before it is published.
- Quiz
- A few questions at the end, so you know you understood it rather than just read it.
Principles
What we care about
- One idea at a time
- Each lesson covers a single topic in depth, so you finish with real understanding, not a list of facts.
- Show, then tell
- Animations show what code and systems actually do. The written lesson explains why, with code you can run.
- Accurate by design
- Every lesson's code is executed and its facts are reviewed before publishing. Updates are dated on the page.
- Free and focused
- No paywalls, no pop-ups, no sign-up. Just the lesson.
The name
Why “Stoa”?
In ancient Greece, a stoa was a long open hall with columns. Anyone could walk in. Teachers taught there for free, and people came to listen and ask questions. Code Stoa is built the same way: open to everyone, free, and made for learning. The columns in our logo are a stoa.
Transparency
How lessons are made
Every lesson starts with the author’s own notes: what to teach, the examples that make it click and the mistakes worth warning you about. AI tools help turn those notes into a lesson and a video script, every claim is checked and every code example is run before anything goes live, and the author reviews and signs off on each lesson personally. Animations are built from code so diagrams stay accurate, and the narration is generated with them, so each video stays in step with the lesson it explains.