Online · 12 courses already available

Learn to code, by writing real code.

Interactive courses in English. Short lessons, exercises that run in your browser, no account. Full Postgres database, isolated JS runtime, regex engine with a dedicated worker and CPython compiled to WebAssembly — all inside your tab.

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Featured:SQL Course JavaScript Course Python Course

12courses

94modules

298lessons

801exercises

~58hours

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SQL Course

Query real data with a Postgres that runs in the browser.

Learn SQL from scratch, in English, with a real Postgres running in your browser.

Beginnerdatadatabase

15 modules57 lessons~11h

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JavaScript Course

The foundations of the web language, with code executed live.

Learn JavaScript from scratch, in English, with an engine that runs your code directly in the browser.

Beginnerfrontendfundamentals

8 modules32 lessons~6h

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Python Course

The language of data and scripting, executed in the browser.

Learn Python from scratch, in English, with CPython compiled to WebAssembly: your code runs directly in the browser.

Beginnerdatascripting

9 modules36 lessons~7h

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Get your hands on the code

No multiple-choice quizzes: write real code and see the results instantly in your browser.

query.sql

1SELECT first_name, salary FROM employees2WHERE salary > 450003ORDER BY salary DESC;

Quality content

Short explanations, rigorous terminology, examples on realistic datasets. For those starting from scratch or shoring up the basics.

SQLPythonJSRegex

No account, no friction

Open the site and learn. Your progress stays in the browser, under your control. No email, no tracker.

localStorage100% OFF

elearner_progress: {sql: "completed"}

elearner_theme: "light"

elearner_locale: "en"

Offline execution in the browser

Each language runs locally in your tab via engines compiled in WebAssembly or executed in separate Web Workers. Safe, instant, and private.

PGlitePostgres WASM

PyodidePython 3.x WASM

V8 RegExpIsolated Worker

WebAssemblyOffline Sandboxing

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