Learning Modules

Free courses with interactive code examples, quizzes, and hands-on exercises. Your progress is saved locally.

Course contributions are welcome! Submit a pull request on GitHub.

Programming Methodology

Learn to write programs that humans can understand. A modern introduction to programming fundamentals using JavaScript, transitioning to TypeScript for type safety and invariants.

Dutch Casadaban26 lessons

HTML & CSS: The Document Model

Learn to build web documents correctly. This course teaches HTML as semantic structure and CSS as a declarative styling system. You will understand why browsers work the way they do and master modern layout systems.

Dutch Casadaban18 lessons

A Philosophy of Software Design

Learn to write code that manages complexity through deep modules, good abstractions, and data-first design.

Dutch Casadaban13 lessons