tutorial

How to play

Ten minutes of reading, or take a tour on the page you are on. Every tour works with a keyboard and a screen reader, and every offer on a page can be dismissed and brought back from here.

Take a tour

Each page has its own short tour. Start one here, or from the offer at the top of the page.

The HUD

The bar at the top of every page. Left to right: your rank and level, the XP bar for the current level, your streak with any freeze tokens as small squares, and your credits. Under it, the main links and the next mission to do. Levels follow one curve: level n needs 100 times n to the power 1.5 XP to pass. Ranks are Script Kiddie, Netrunner, Data Ghost, Model Smith, Neural Architect and Singularity.

The tree

Ten modules on five branches. Each node carries its module's glyph, large, so you can find a module by shape:

Vectors and TensorsNumbers in rows and columns. Everything else is built from these.
Gradient DescentRoll a ball down a bowl. The slope tells you which way is down.
Linear RegressionDraw the line that misses every point the least.
Logistic RegressionThe same line, bent into a yes or a no.
K-MeansNo labels. Find the groups anyway.
Decision TreesTwenty questions, played by a machine.
Multi-Layer PerceptronStack lines and bends until the shape appears.
BackpropagationBlame, passed backwards through the network.
Convolutional NetworksA small window slides over the picture and looks for edges.
Embeddings and AttentionWords as points. Attention decides which points matter to which.

A dim, outlined node with a small lock is locked; the panel beside the tree says exactly what opens it. A module unlocks the ones after it when it reaches Silver. The larger five-sided nodes are the bosses, one per branch.

A module page

Cover: branch, difficulty, time, XP available, and links to the sections.
Briefing: short sections, plain words, with analogies.
Live demo: the playground. Running it once is the Bronze tier.
Missions: Predict, Tune, Debug and Code, in order; each unlocks the next.
In production: where the idea is used for real.
Code samples: the actual C++ the engine runs, and the TypeScript that calls it.
Debrief: your tier, XP per mission, what you unlocked.
Share kit: copy for three networks and a card. Sharing pays credits once per module.

The four missions

PredictA quiz. Lock an answer, see why, then run the demo at exactly those settings to see it happen. Scored by the fraction right; 80 percent is Silver for the module.
TuneThe demo with most controls locked and a target on its chart. Hit the target inside a budget of steps; fewer steps and fewer attempts score higher.
DebugA function with a bug in it, in the editor, and tests underneath. Make them pass. Scored by how many runs it took.
CodeWrite the function from a starter, run the visible examples as often as you like, then submit against hidden tests. All of them or no clear. Passing is Gold for the module.

Every clear pays XP by medal: Bronze from 40 percent, Silver from 60, Gold from 80, Platinum from 95. Beating your own medal on a mission pays the difference; repeating it pays nothing, so grinding does not work and improving does.

Hints cost tiers

Three hints per mission, from a nudge to nearly the answer, revealed in order. With no hints you can reach Platinum; one hint caps you at Gold, two at Silver, three at Bronze. The cap is shown before you reveal anything, and a reload does not reset it.

Bosses

One per branch, open once every module on the branch is Silver. Four stages of every mission type on one clock, an HP bar that drops a quarter per stage, and hints that all count against one medal. Clear it with no hints and every module on the branch turns Platinum.

Streaks and the daily glitch

Clear one mission a day to keep the streak. Every seventh day earns a freeze token, up to three; a token covers one missed day, spent automatically. The daily glitch is one module with a twist and a bonus, the same for everyone, new at midnight.

Credits

Credits come from missions and from sharing a completion card. They buy how things look: HUD themes, cursor trails, avatar frames, titles. Nothing in the shop changes XP, tiers, hints or what is unlocked.

Badges

Achievements sit on your profile as big glyphs. A few of the 41:

Jack InClear your first mission.
Bronze AgeEarn a bronze.
Silver LiningEarn a silver.
Gold StandardEarn a gold.

Accessibility

Keyboard: every control, including sliders, quiz answers, the tree, hints and the editor, works without a mouse. See the key list below.
Screen readers: every control has a name, the XP bar and the boss HP bar are real progress bars, charts and canvases carry a text description of what they show, every tree node is in a list beside the canvas, and tours and toasts announce themselves through live regions.
Reduced motion: if your system asks for less motion, the app stops the flicker, the particle field and the cursor trail, does not auto-play the ball, and draws the tree and the demos in two dimensions.
Phones: the tree and the demos are drawn in two dimensions below 768 pixels. The tree page has a "show in 3-D anyway" switch.
Contrast: the neon on void palette meets WCAG AA for text, and every state (locked, cleared, selected) is shown by shape or outline, never by colour alone.
Focus: a visible cyan ring on every focused control; dialogs move focus in and return it when they close.

Keys

Key	Does
Tab and Shift Tab	Move between controls. The skip link at the top of every page jumps to the content.
Arrow keys	Move a slider by one step. Home and End jump to its ends. In the tree, Enter or Space picks the focused node.
Enter or Space	Press a button, lock a quiz answer, reveal a hint.
Escape	Closes the level-up dialog and the tour.
Left and Right arrows in a tour	Previous and next step.
Control and M in the code editor	Toggles whether Tab indents or moves focus. Alt and F1 opens the editor's own accessibility help.