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37
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1,900+
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Courses sequenced into a route — you see where it starts and what you’ll ship at the end before you commit an hour.

Backend Engineer

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

intermediate·~80 hours·8 courses·go · sql
startGo Fundamentals
SQL Fundamentals
Build Redis
Build an HTTP Server
+3 more
shipBuild OAuth 2.0
Start this path →

37 languages, each with a real track

Fundamentals → intermediate → advanced. Not “hello world in 37 flavors.”

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Every completed course issues a certificate — and it’s only issued when every graded exercise has passed on the executor. Nothing to buy at the finish line.

  • LinkedIn-ready. A public verification page with a credential ID — one click adds it under Licenses & Certifications.
  • Lives in your GitHub README. Work in your own editor and your repo’s badge shows live progress — then turns into the certificate when you finish.
  • Means something. It certifies passed tests, not watched videos — the same bar for everyone.
Pick a course to finish

You can’t cheat here. Your code either passes the tests or it doesn’t.

That’s the whole point.
Every exercise verified end-to-end on the executor — all 1,900+ of them
Your code persists — leave mid-lesson, your draft is there tomorrow
Free while we grow. No paywall mid-course, no credit card, ever

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We invite academics to review our curriculum — correct it, deepen it, and get credited on the course itself: your name, title, and institution, plus a verifiable Certificate of Peer Review.

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The first test you make pass takes about two minutes.

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Free forever · no credit card · 179 courses · free certificates