Bite-sized lessons, quizzes, and real projects where you write real code in your browser, run it instantly, and level up. JavaScript, Python, SQL, and more. No setup, just start.
Follow a guided program from zero to job-ready, or grab a single course. Every course starts free.
Where most learners are right now.
Go past useState: refs, reducers, context, effects, data fetching, and your own custom hooks.
Handle time and the network: promises, async and await, JSON, fetch, and requests that fail.
Style real pages with CSS: selectors, the cascade, color, the box model, backgrounds, and typography.
Lay out real pages with flexbox, CSS grid, positioning, and responsive design that works on any screen.
Data structures and algorithms in JavaScript: Big O, stacks, queues, linked lists, searching, and sorting.
Git from zero: commit, branch, merge, undo, and tag real repositories in a live terminal.
Not videos to watch. A playground to build in. Here is what is inside.
Run your code and see it checked against the lesson goals right away. Learn from mistakes in real time.
No passive videos. Almost all of your time is spent writing real, working code.
Ordered courses that build on each other, so you always know what to learn next.
Streaks, daily goals, and email reminders turn learning to code into a daily ritual.
Use your skills to build challenges and projects you can actually show off.
Stuck? Get a nudge in the right direction, without the answer handed to you.
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