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Theebug — Learn to Code by Doing
Start Learning
Explorer···
▼THEEBUG
index.tsxlearn.mddocs.mdabout.mdfaq.mdleaderboard.mdupdates.md
index.tsx
THEEBUG›index.tsx
// index.tsx

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

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

// click Debug
7
courses
49
levels
3
difficulty tiers
100%
free
// 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
// why theebug

Not another blank-page tutorial

Traditional tutorials
A blank editor and a wall of text — tutorial paralysis before you've typed a line.
Copy-paste along with a video, without ever testing if you actually understood it.
No feedback until something breaks, sometimes hours later.
Theebug
Real, working code with just the puzzle pieces missing. You're never starting from zero.
Every block you drag is checked instantly — right or wrong, you know immediately.
Debug the Worm reacts to every single drop — no waiting, no guessing.
// courses

Pick a language, start dragging

7 courses, 49 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!"
// faq

Quick questions, answered

Is Theebug free?

Yes — completely free, no account required to play.

Do I need any coding experience?

None! Every course starts from the basics and builds up one concept at a time.

What languages can I learn?

JavaScript, Python, HTML, CSS, React, Node.js, and MongoDB today — frontend, backend, and databases — with more courses on the way.

See all FAQs

Your next level is one drag away

49 levels across 7 languages — free, no account needed.

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