Lesson 01 / Learning to read code

Understanding begins with close reading.

Short coding exercises, clear explanations, and a learning rhythm that turns correct guesses into real skill.

Start your first exercise Browse the library
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Today's note · TypeScript01 / 05 · Intermediate

What gets logged?

const values = [1, 2, 3];
values.map(n => n * 2);
console.log(values);

Capypad in numbers

Corpus snapshot · July 13, 20264,886

1,299 Learn · 2,198 Quiz · 1,389 Debug

Programming languages10

From Java to C#

Training modes4

Quiz, Learn, Debug, Daily

Answers per question4

One decision, one clear explanation

Chapter 02 / The method

Not more content. Better learning loops.

Capypad trains the exact moment when developer knowledge forms: reading code, making a prediction, and understanding the difference.

01think first →

Read

A compact snippet without distractions. Runtime, types, and side effects become visible.

02commit →

Decide

Four plausible options make you execute the code clearly in your head.

03understand ✓

Place it

The explanation shows not only what is right, but why the other paths mislead.

Chapter 03 / Four perspectives

One look at code. Four ways to train.

Choose the format that fits today’s learning moment.

01 / Quiz

Predict.

Run code without running it. Four answers and one explanation for your developer intuition.

read → choose → reveal
02 / Learn

Anchor.

Short knowledge cards with spaced repetition. Difficult snippets return sooner; secure ones later.

new → due → mastered
03 / Debug

See causes.

Find real logic, async, type, and security bugs. Learn not only the bug, but its pattern.

symptom → cause → fix
04 / Daily

Keep going.

Five shared questions every day. A small anchor for routine, streak, and shareable results.

5 questions / every day

Account-backed progress

Capypad remembers what you almost knew.

With sign-in, your streak, history, weak spots, and Leitner progress stay in sync. You can play anonymously and view or share results immediately; persistent progress remains account-bound.

Review today3 due
L1
Promise orderJavaScript · Async
now
L2
Ownership & BorrowingRust · Memory
today
L4
Window FunctionsSQL · Queries
in 6 days
Chapter 04 / Your stack

Ten languages. The same precise question.

Train concepts where you need them in daily work — from garbage collection to ownership.

Margin notes / FAQ

Questioning capybara

Looking for an answer, not an excuse? Here are the important ones.

Asked briefly,
answered honestly.

Do I have to sign in?

No. You can start Quiz, Debug, and Daily anonymously; your result appears immediately and can be shared through an unguessable link. An account adds sync, history, streak, and persistent weak spots.

Does AI generate questions for me?

Not in the browser. Capypad content is produced, checked, and curated through a trusted admin and CLI pipeline. Users never enter an API key or choose an arbitrary model.

Is Capypad free?

Yes. The current public beta is free. Features and data may still change during the beta.

How does Learn work?

Learn uses a Leitner-style spaced-repetition system. Your rating determines when a snippet is due again. This persistent learning progress is saved with your account.

Which difficulty levels are available?

Beginner, intermediate, and expert. You can also filter by language, framework, and topic where available.

Read the next code block differently.

Start anonymously with a short exercise. If Capypad helps, you can save your progress with an account afterward.

Capybara celebrates a successful learning momentStart quiz