Interactive courseware

Courses that show their work.

From your first line of Python to transformers and diffusion models. Every idea arrives as something you can run, step through and break — computed live in your browser, not screenshotted from someone else's notebook.

Free · No sign-up · Nothing to install · Works offline once loaded

Running right now, in this page
A real chapter widget — press play, or scrub it. Open the chapter →

4

courses, beginner to advanced

118

chapters, all written and live

862

exercises that grade themselves

0

installs, accounts or downloads

01

Where do you start?

Pick the sentence that sounds most like you. Each one goes straight to the first chapter of the course that fits — no account, no setup.

02

How they fit together

Each course stands alone, but this is the order that costs the least effort — every step assumes only what the step before it taught.

Already comfortable with Python? Start at step 2. Already comfortable with algorithms? Start at step 3.

03

The six courses

The coloured bar under each one is its curriculum: a segment per chapter, shaded by which part of the course it belongs to.

04

How a chapter works

The same three beats, 118 times. Read it, run it, then prove you can do it.

BEAT 01

Read

A short guide in plain English. Every idea gets an analogy before it gets a definition — a hash table is a coat-check desk, a Bloom filter is a guest list you can only stamp.

Key terms are underlined; hover one and the glossary definition appears without leaving the page.

BEAT 02

Run

A playground beside the text that does the real computation in your browser. Animations are frame-by-frame and fully scrubbable — step backwards through a quicksort partition as many times as you need.

Nothing is a video. Change the input and the whole thing re-runs.

BEAT 03

Prove

Exercises that grade themselves. You write Python in the editor, press check, and a real test suite runs against your code — in the browser, with no server.

A failure names the exact case: expected 4, got 5 — the middle interval was dropped.

05

Also on the hub

Things that are not part of a course: standalone toys, and work in progress.

Interactive modules

Self-contained pages with no reading order and no prerequisites. Open one, pull the mechanism apart, leave with an intuition.

All interactive modules →

The lab

Experiments, commissioned pages and things still being built. Rougher than the courses, and that is the point.

Everything in the lab →

Start with one chapter.

It takes about twenty minutes, it runs in this browser, and nothing asks you to sign up.

Open the first chapter →