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Theebug — Learn to Code by Doing
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▼THEEBUG
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index.tsx
THEEBUG›index.tsx
// index.tsx

You don't write the code.
You finish it.

Real JavaScript, Python, HTML, and CSS with a few pieces missing. Drag the right block into place and watch it resolve — Debug the Worm coaches every drop.

// click Debug
// how it works

Three steps, every level

1
Read the objective
Debug explains the challenge in plain English in the right panel — no jargon.
2
Drag the right block
Pick a code block from the tray and drop it into the glowing empty slot.
3
Get instant feedback
Correct turns green and Debug cheers. Wrong turns red — try again, no judgment.
Built with the real thing
  • Full syntax highlighting in dark & light themes
  • Drop zones inline inside real code structure
  • Terminal shows system logs (not the coach!)
  • File sidebar tracks your progress
// courses

Pick a language, start dragging

4 courses, 31 levels total. Jump into any track, or browse the full catalog.

JavaScript
Variables, functions, arrays, and conditionals — the fundamentals of JS.
11 levels
Python
Variables, functions, lists, and conditionals — the fundamentals of Python.
9 levels
HTML
Structure the web with tags, attributes, and semantic elements.
5 levels
CSS
Style pages with selectors, the box model, flexbox, and more.
6 levels
Browse all courses
Debug the Worm
Sad
Neutral
Party
// meet your coach

Debug never leaves your side

Every action triggers a reaction from Debug. Correct answer? He wiggles with joy. Wrong block? He gives you a gentle nudge. Level complete? Pure celebration. All dialogue lives in the right panel — the terminal is strictly for system logs.

"Drag the return block into the empty slot to complete the function!"
"Perfect! a + b adds both parameters! You're getting it!"
"Hmm, that's not quite right. Try a different block!"

Your next level is one drag away

31 levels across 4 languages — free, no account needed.

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