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Build real projects.
Every course ends in something you can show — a deployed app, an analysed dataset, a finished portfolio piece. No quizzes pretending to be skills.
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An AI tutor that watches its own work. Citation-grounded answers, tool calls you can audit, evals you can read. Watch it think — or just click through.
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Why Lumen
01
Every course ends in something you can show — a deployed app, an analysed dataset, a finished portfolio piece. No quizzes pretending to be skills.
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Async lessons with per-step progress, an AI tutor that answers from the course itself, and a review queue that surfaces what to revisit next.
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MIT-licensed, self-hostable. Your courses, your data, your certificates — yours to keep forever, with or without us.
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Free for learners, free to self-host. Pay if and when you want managed hosting.