CodingNeed.

ONE CONCEPT. ONE EXPERIMENT. ONE STEP FORWARD.

From “I get it”
to “I built it.”

Learn programming by predicting, running and changing real code. Start with the basics. Grow into the engineering decisions that matter.

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your-next-step.jsLEARN BY DOING
// Keep the useful ideas.
const skills = new Set();

skills.add("understand");
skills.add("experiment");
skills.add("build");

console.log(skills.size);
3 skills. Countless possibilities.Small experiments build lasting understanding.
21focused courses & workshops
62published lessons
18interview prompts
4browser runtimes

A CLEAR PLACE TO START

Your next skill is within reach.

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UNDERSTANDING THAT STICKS

Learn a little.
Use it straight away.

Every foundation lesson follows the same path, so you spend your energy on the idea.

  1. Understand

    A clear explanation and a worked trace.

  2. Predict

    Think through the result before pressing Run.

  3. Experiment

    Run working code, then change one thing.

  4. Build & revisit

    Solve the challenge, compare approaches and return for spaced revision.

READY FOR THE NEXT LEVEL

Learn to explain the trade-offs.

Build an LRU cache, validate unknown JSON, process event streams and write SQL window queries. Compare costs, investigate edge cases and practise your reasoning.