What's new

The latest changes to the book, newest first. Each entry says what changed for a reader.

16 October 2026DiagramsLessonsPracticeMobile

Pictures redrawn as diagrams you can step through, shorter long lessons, more recall practice, and a tidier layout on phones.

• Diagrams instead of pictures. The remaining generated illustrations are now diagrams, stepped frames and small calculators drawn by the book itself: the stack, the three places a value can live and how long each lasts, the address map, and byte layouts you can change and watch. They follow your colour choice and fit a phone screen.
• Long figures fold. The stack-frame figure keeps the picture and the step you are on in view; the full step text, the stack-cookie table and the list of defences open when you want them, so the figure is about 40 to 50 per cent shorter.
• Shorter long lessons. Where a lesson repeated something another lesson teaches in full, it now says so in one line and links to the lesson that owns it. Detail that only some readers need sits in a closed “Optional reference” on the same page. Several dozen lessons across the book were trimmed this way, and the links and saved progress did not change.
• More recall practice. New typing drills hide the function names and arguments of real calls in Lessons 6.5, 6.8, 7.6, 8.2, 12.1 and 13.2, and Lessons 5.2 and 6.6 have new questions.
• A tidier layout. Phones have a settings button in the header, the Notes button sits beside the chat button, and a comment closes with a small ✕. Numbered steps are joined by a line, cards are more compact, and accordions and tabs match the rest of the book. Short labels in Mermaid diagrams are no longer cut off.

8 October 2026LessonsIllustrationsInteractives

Clearer examples, original mechanism pictures, and more ways to explore what changes.

• A picture in every lesson. Original drawings now explain each lesson’s mechanism beside the relevant paragraph. Small byte, input and buffer animations begin as still pictures and play only when you choose.
• Change a scene’s inputs and see its result. Explore pathfinding, camera projection, a server’s pickup decision, fresh button presses, repeated event reports and snapshot changes. The behaviour-tree editor lets you change a small tree and watch its next tick.
• More Rust and assembly foundations. New instruction references trace each operation. Rust lessons explain useful collection, borrowing, error-handling and cleanup patterns. The Rust Primer includes optional recall practice with hidden names, parameters and calculations, plus hints and an answer reveal.
• Reader controls work together. Hide or restore comments and side panels, add your own margin comments, navigate Notes with the keyboard and download a compact cheatsheet. Appearance choices retain the original design as their default.

5 October 2026SimulationsReaderLayoutSound

Diagrams now show the mechanism; the reading edition keeps pictures and speaks the explanation.

• Anti-cheat from the defender’s side: Chapter 15 adds nine lessons on server authority, Macrodox measurements, local protection, false positives, layered review, and safer game design. Nine compact simulations show the underlying mechanisms.
• One quiz per lesson replaces separate inline checks. Source 8.9 and Chapter 15 now draw from page-specific pools, with separate New quiz and Retake controls. Earlier questions stay on their own pages.
• Mark chapters done on All lessons. A completed chapter gets deeper green checks, and optional completion sounds respect the effects setting.
• How the Source Engine Works: Lesson 8.9 follows versioned interfaces, entity data, input commands, prediction, and server correction. Its simulation shows which commands a client must replay after a reply.
• All 42 step-through diagrams now use causal scenes: bytes copy into buffers, calls follow changed routes, stacks push and pop, and geometric points project onto a viewport.
• Reader editions keep compact diagram and table pictures. Narration skips dense visual labels, long numeric literals, and optional hover-card bodies. Register names are spaced for speech; voice selection stays chosen as voices load.
• The toy CPU lab marks its next action, read source, copied byte, and changed registers. The pointer tracer now uses its lesson’s capture and shows each calculation and read separately.
• Compact controls, narrower table columns, plain section headings and navigation, and short margin explanations make the page calmer.
• Original music and rain loops, plus gentle optional button sounds, start off. Play, pause, stop, and volume controls are in the reader settings.
• Original CC0 pictures explain map layers and NPC sensing. Tiny sprites make the path search easier to follow, and an optional input GIF starts as a still. Image credits record their public-domain dedication and reproducible source.

3 October 2026New lessonsGame enginesMobileProgressHover cardsReader mode

Two new lessons, more on how a game works, a calmer layout on phones, and ways to keep track of what you have read.

• Two new lessons. 4.2 How an Engine Orders and Shares Its Work follows how systems share data through resources and events, how one frame’s work is ordered and run in parallel, and how an engine notices only what changed. 6.6 How a Game Reads Input follows a key press, a stick, and a mouse from the device to a game action.
• Some lesson numbers moved up by one. In Chapter 4, lessons 4.2 to 4.12 are now 4.3 to 4.13, and in Chapter 6, lessons 6.6 to 6.9 are now 6.7 to 6.10, to make room for the two new ones. Lesson links did not change, and neither did the ticks you have already saved.
• More on how a game works, inside the lessons that need it. Real time and game time, and why a long frame is clamped (4.1); extrapolation (4.7); local and world copies of a transform, engine axis conventions, several cameras, and texture coordinates (7.1); who decides whether an object is drawn, HDR, anti-aliasing, and the renderer’s own copy of the world (7.2); how long an asset stays loaded and when a changed file is picked up (9.1); two ears and falloff (9.4); several windows (6.7).
• A calmer layout on phones. The chat button steps out of the way while you scroll, long file names in a lab’s source card no longer widen the page, “On this page” stays as one bar, and the listening controls take less room in landscape.
• Mark lessons and chapters done. A tick appears beside each finished lesson in the lesson list, each chapter shows how many of its lessons are done, and the contents page and the home cards show the same progress. It is saved in your browser only.
• Hide either side panel from the panel itself. The lesson list and “On this page” each have a Hide button, and a tab at the screen edge brings the panel back.
• Hover cards, used sparingly. A glossary word shows its definition when you hover, focus, or tap it, but only where the book first uses the word, not every time it appears. A mention such as “Lesson 2.1” is now a link that shows what that lesson covers. Lessons can also write cards of their own: an example, a reference, a tip, an alternative, a recommendation, or a closer explanation, each labelled by kind. The Reader theme panel has a Hover cards On/Off choice if you would rather not see them.
• Reader mode keeps its controls on screen. Back, play or pause, forward, stop, a speed button, and a way out of reader mode stay at the top while you scroll. Back and forward skip a paragraph, the speed button steps from 0.75× to 2× and is remembered, and on a phone the bar fits in two short rows.
• How games work. New sections explain the parts of a game: the frame and its timing, entities and scenes, transforms and quaternions, 2D and 3D rendering, shaders, animation, picking, windows, interfaces, assets, glTF models, and audio. The How games work page maps each part to its section.
• Lesson components. Steps, tabs, accordions, fields, maths, panels, worked examples, captions, link buttons, tooltips, and more are now used across the lessons and pages, wherever they help. The components page shows each one.
• A chat button for asking questions about the book appears on every page. Its hint text names the lesson, chapter, or section you are reading, and it takes the chapter’s colour. Move it to any corner, or turn it off, in the Reader theme panel.

Read lesson 4.2Read lesson 6.6

2 October 2026ReaderColour

Calmer, more consistent themes, and better listening and printing.

• Reader themes blend their colours more consistently, and each theme’s reading colours follow its own palette.
• Diagram playback is clearer, every lesson has a listening edition, and a single chapter can be printed on its own.

1 October 2026DiagramsReader

Animated diagrams and reader appearance controls.

• Animated walkthroughs now cover 42 lessons, three in every chapter. Each can be played, stepped through, or read in full, and respects your reduced-motion setting.
• The reader theme panel gained controls for diagram backgrounds, text size, spacing, and heading style.

30 September 2026LessonsColour

A firmware lesson, deeper fundamentals, and colour with a meaning.

• A new lesson on firmware and bare-metal Rust, and deeper explanations of game fundamentals.
• Chapters were rebalanced and reader spacing improved.
• Every colour now has a documented role, and the same colour always means the same thing.

29 September 2026Lessons

The chapters were reordered so each idea follows the ones it needs.

• The later chapters were reordered around what each lesson needs from the ones before it.
• A Rust primer was added, and the whole book was revised as a guide, a reference, and a tutorial.

28 September 2026Lessons

The teaching progression was revised.

• Lessons now introduce each idea before they use it, and the opening chapters build up from visual foundations to games and hacking fundamentals.