From symptom to measurable practice

A compact lab for debugging decisions

Practice stays focused on evidence while ten skills, a rating, weekly solved counts, streaks and achievements make progress visible.

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const theory = inspect(symptom);
const change = test(theory);
assert(change.explains(symptom));

From code to learning

Choose your first language

Nine verified programming languages. The interface and feedback support five languages, while editorial documentation initially publishes in English and Brazilian Portuguese.

1Choose a language
2Investigate the bug
3Check the solution
4Read explainable feedback
5Track your progress

PythonPractice now →JavaScriptPractice now →TypeScriptPractice now →JavaPractice now →C#Practice now →SQLPractice now →KotlinPractice now →SwiftPractice now →C++Practice now →

Interface and feedback: English, Português, Español, العربية, 한국어. Published docs: EN / PT-BR.

Adaptive difficulty from progress

The next difficulty can move with recent results and skill level. Rating is reported separately and does not choose difficulty.

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Ten skills with their own levels

Each solved challenge awards 60, 100, 140, 180 or 220 XP per inferred skill. Skills follow their own level 1–5 curve.

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Rating and weekly ranking

A rating inspired by Elo reflects solved results, challenge difficulty and time. The weekly board counts solved challenges.

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Streaks and achievements

A valid daily practice keeps the local-day streak moving; reachable milestones recognize consistency and skill progress.

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