Sample lessons

This course is for a developer who already writes basic HTML and CSS — you can set color, padding, and width, and style a simple page — but Flexbox still feels like guesswork. You set justify-content and the thing moves the wrong way; you reach for align-items and nothing happens. The fix is not memorizing more properties. It is one mental model: a flex container has two axes, and every alignment property is just "which axis, which direction." Once you see the axes, the properties stop being a coin flip.

This course is for a developer who already writes JavaScript — you use .then(), you write async/await, you call setTimeout — but the order things run in still feels like magic. You log A before B in the source and B prints first; a .then() you wrote last somehow runs before a setTimeout(fn, 0) you wrote earlier; you can't say what await actually does to the line under it. The fix is not more syntax. It is one mental model: a single call stack, a microtask queue, and a task queue, with an event loop deciding who runs next. Once you can see those three places, the ordering stops being magic and becomes something you can predict on paper.

This course is for a developer who has pasted plenty of regexes off Stack Overflow but freezes when asked to write or even read one. You can tell it "matches an email, probably," but \d, , +, ^, (…), and .+? are still line noise. The fix is not collecting more patterns to paste. It is learning the small alphabet a regex is built from, one piece at a time — literals, character classes, quantifiers, anchors, groups, alternation, and greedy-vs-lazy — until you can look at an unfamiliar pattern and say out loud what it does. We use JavaScript's regex syntax as the concrete vehicle, but the pieces transfer to almost every language.