Python, from zero
Every idea in the language built up from nothing, and every line on every page really ran.
- 50 lessons
- 4 h read
- Beginner to advanced
Node.js, from zero
JavaScript on your own machine, from the first console.log to a program you can ship, and every line of output on every page really ran.
- 50 lessons
- 4 h read
- Beginner to advanced
TypeScript
An eighteen-lesson TypeScript course for people who already write JavaScript. Every sample is checked by the real compiler, and every counter-example shows the error it actually produces. No install, works offline.
- 18 lessons
- 3 h read
- For JavaScript developers
OOP in JavaScript
A fifteen-lesson course on object-oriented JavaScript for complete beginners. Every example runs on the page. No install, no network, works offline.
- 15 lessons
- 2 h read
- Complete beginners
DSA & Interviews
A twenty-four lesson course on data structures, algorithms and technical interviews for complete beginners. Every example runs on the page. No install, no network, works offline.
- 24 lessons
- 5 h read
- Beginner to interview-ready
Flutter and Dart, to senior
The language properly, then the judgement calls a senior interview is actually testing.
- 39 lessons
- 3 h read
- Intermediate to senior
AI Engineer, from zero
What the job actually is, and every idea underneath it built from scratch.
- 31 lessons
- 3 h read
- From zero
Cloud, DevOps and AWS, from zero
What the job actually is, and every tool underneath it run for real, not just described.
- 47 lessons
- 2 h read
- From zero
Exercises
Practice exercises for JavaScript, TypeScript and HTML/CSS. Every solution runs and tests itself in your browser, with no install and no network.
- 982 exercises
- JavaScript, TypeScript, HTML and CSS