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Pick a system. Build it from scratch. Every lesson is choose → write → run, until it clicks.

80+ build-from-scratch courses · 9 languages · no credit card

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Sequenced courses that take you from zero to job-ready.

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Backend Engineer

intermediate~80h

The infrastructure under every web service — Go, SQL, caches, queues, and the protocols that connect them.

Go FundamentalsSQL FundamentalsBuild Redis+5 more

Frontend Engineer

intermediate~65h

Master the browser end of the wire — JavaScript, TypeScript, then build the framework you depend on every day.

JavaScript FundamentalsTypeScript FundamentalsJavaScript Advanced+4 more

Full-Stack Developer

intermediate~90h

Both ends of the wire: TypeScript on the client, plus a backend language and the protocols that connect them.

JavaScript FundamentalsTypeScript FundamentalsSQL Fundamentals+4 more

DevOps / SRE

intermediate~70h

Run the systems other engineers build — Bash and Go for tooling; Docker, CI, and observability for the platform.

Bash FundamentalsGo FundamentalsBuild Docker+4 more

Data Scientist

beginner~60h

Python, R, and SQL — the canonical trio of data analysis. Plus the data structures behind efficient queries.

Python FundamentalsPython in PracticeR Fundamentals+4 more

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Each card opens a structured Fundamentals → Intermediate → Advanced track. Tap the > chevron to reveal all 37 languages.

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