# Uma coletânea com bibliografia em cada capítulo

> Três ensaios de três autores, cada um num documento próprio em buildBundle e cada um fechado por uma lista Chicago autor-data só com as obras que cita.

- Versão HTML: https://postext.dev/pt/cookbook/edited-volume-chapter-bibliographies
- Receita Nº 098 · Estrutura do livro · Nível 3 (Avançado) · Saídas: Canvas, PDF
- Gêneros: Artigos e trabalhos acadêmicos, Livros didáticos
- Requer postext ≥ 1.12.1, postext-pdf ≥ 1.12.1 · testada com 1.19.1, postext-pdf 1.19.1 em 2026-10-06
- Páginas: [1](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p01.webp?v=07bfe3ea), [2](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p02.webp?v=07bfe3ea), [3](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p03.webp?v=07bfe3ea), [4](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p04.webp?v=07bfe3ea), [5](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p05.webp?v=07bfe3ea), [6](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p06.webp?v=07bfe3ea), [7](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p07.webp?v=07bfe3ea), [8](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p08.webp?v=07bfe3ea), [9](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p09.webp?v=07bfe3ea), [10](https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/p10.webp?v=07bfe3ea)
- PDF: https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/edited-volume-chapter-bibliographies.pdf?v=07bfe3ea
- Abrir no Sandbox: https://postext.dev/pt/sandbox#recipe=edited-volume-chapter-bibliographies&lang=en (.postext: https://postext.dev/cookbook/edited-volume-chapter-bibliographies/en/edited-volume-chapter-bibliographies.postext)
- Última atualização: 2026-10-01
- Outros idiomas: [en](https://postext.dev/en/cookbook/edited-volume-chapter-bibliographies.md), [es](https://postext.dev/es/cookbook/edited-volume-chapter-bibliographies.md), [ca](https://postext.dev/ca/cookbook/edited-volume-chapter-bibliographies.md), [zh](https://postext.dev/zh/cookbook/edited-volume-chapter-bibliographies.md), [ja](https://postext.dev/ja/cookbook/edited-volume-chapter-bibliographies.md), [ar](https://postext.dev/ar/cookbook/edited-volume-chapter-bibliographies.md)

## Em poucas palavras

Um livro de ensaios de autores diferentes. Cada ensaio traz o nome do autor sob o título e termina com a sua própria lista de referências, como nas coletâneas.

## O que você vai compor

*The Working Page*, uma pequena coletânea de ensaios sobre a história da impressão, organizada por dois pesquisadores e escrita por três. Cada ensaio chega do seu autor como um arquivo Markdown com um bloco BibTeX próprio, e é assim que o livro o mantém: um volume de 155 × 235 mm em Libre Caslon, uma folha de rosto vermelha e capítulos que abrem com um número, um título e o nome do autor. Cada capítulo fecha com a sua própria lista de References em Chicago autor-data, que contém só as obras citadas naquele ensaio. *The Printing Press as an Agent of Change*, de Eisenstein, é citado por dois autores e por isso aparece nas duas listas; a *New Introduction to Bibliography* de Gaskell faz o mesmo nos capítulos 1 e 3.

**Esta receita responde a:**

- Como faço para dar a cada capítulo de uma coletânea o nome do seu autor e a sua própria lista de referências?
- Como cito obras e monto a bibliografia em APA, IEEE ou outro estilo de citação?

## A resposta curta

```js
// script.js, linhas 39–55
// Citations are [@key] in the text; each contributor's BibTeX goes in a :::references block
// in their own chapter. Register the engine once, before the first build.
registerCitationEngine(createCiteprocEngine({ styles: STYLES, locales: LOCALES }));
const citations = {
  style: 'chicago-author-date', // the humanities' author-date: (Eisenstein 1979)
  bibliography: {
    // 'chapter': a :::bibliography lists the works its own document cites, so a work two
    // contributors cite appears in both lists. 'book' (the default) would print one list,
    // after the last chapter. The scope is per document, not per H1: each essay must be a
    // document of its own in buildBundle (see the chapters region).
    scope: 'chapter',
    title: '', // no bold title paragraph: each chapter has its own ## References heading
    fontSize: em(0.9), lineHeight: pt(12.4), hangingIndent: mm(5), entrySpacing: pt(2.6),
  },
};
// Numbering and disambiguation still see the whole book: two Smiths of 2001 in different
// chapters would print 2001a and 2001b, as one bibliography would.
```

## Ingredientes

**Ensina**

- [Bibliografia a partir das referências](https://postext.dev/pt/docs/document-format.md#citações-e-bibliografia): A lista de obras citadas, montada a partir das referências do documento (front matter ou um bloco BibTeX) no lugar onde estiver :::bibliography ou depois do último capítulo.
- [Citações em um estilo de citação](https://postext.dev/pt/docs/document-format.md#citações-e-bibliografia): Obras citadas como [@chave, p. 33] e formatadas em um estilo CSL (APA, Chicago, MLA, IEEE, Vancouver, ISO 690, GB/T 7714…) escolhido nas configurações, com link para as respectivas entradas.

**Também usa**

- [Livros compostos capítulo a capítulo](https://postext.dev/pt/docs/configuration.md#diagramar-e-renderizar-um-pacote)
- [Atributos de título](https://postext.dev/pt/docs/document-format.md#atributos-de-título)
- [Aberturas desenhadas](https://postext.dev/pt/docs/configuration.md#largura-e-design-avançado)
- [Sumário](https://postext.dev/pt/docs/configuration.md#sumário)
- [Cabeços e fólios](https://postext.dev/pt/docs/configuration.md#cabeços-e-rodapés)
- [Cabeços por tipo de página](https://postext.dev/pt/docs/configuration.md#elementos-de-texto)
- [Estilos de título](https://postext.dev/pt/docs/configuration.md#estilos-de-título)
- [Capítulos sem número](https://postext.dev/pt/docs/configuration.md#estilos-de-título)
- [Capas, folhas de rosto e colofões](https://postext.dev/pt/docs/configuration.md#estilos-de-título)
- [Ancoragem de elementos de design](https://postext.dev/pt/docs/configuration.md#posicionamento-de-elementos)
- [Boxes flutuantes](https://postext.dev/pt/docs/configuration.md#o-contêiner-callout)
- [Margens espelhadas](https://postext.dev/pt/docs/configuration.md#margens-espelhadas)
- [Paleta de cores semântica](https://postext.dev/pt/docs/configuration.md#paleta-de-cores)
- [Exportação para PDF](https://postext.dev/pt/docs/configuration.md#geração-de-pdf)
- [Boxes](https://postext.dev/pt/docs/configuration.md#estilos-de-boxe)
- [Equilíbrio de colunas](https://postext.dev/pt/docs/configuration.md#equilíbrio-de-colunas)
- [Títulos numerados](https://postext.dev/pt/docs/configuration.md#sobrescritas-por-nível)
- [Cor do papel](https://postext.dev/pt/docs/configuration.md#página)
- [Fontes incorporadas ao PDF](https://postext.dev/pt/docs/configuration.md#por-que-um-provedor-de-fontes)
- [Cabeços por seção](https://postext.dev/pt/docs/configuration.md#estilos-de-título)

**A configuração em resumo**

- [`bodyText`](https://postext.dev/pt/docs/configuration.md#texto-do-corpo), [`calloutStyles`](https://postext.dev/pt/docs/configuration.md#estilos-de-boxe), [`citations`](https://postext.dev/pt/docs/configuration.md#citações), [`colorPalette`](https://postext.dev/pt/docs/configuration.md#paleta-de-cores), [`footer`](https://postext.dev/pt/docs/configuration.md#cabeços-e-rodapés), [`header`](https://postext.dev/pt/docs/configuration.md#cabeços-e-rodapés), [`headingStyles`](https://postext.dev/pt/docs/configuration.md#estilos-de-título), [`headings`](https://postext.dev/pt/docs/configuration.md#títulos), [`layout`](https://postext.dev/pt/docs/configuration.md#diagramação), [`locale`](https://postext.dev/pt/docs/configuration.md#hifenização), [`page`](https://postext.dev/pt/docs/configuration.md#página), [`toc`](https://postext.dev/pt/docs/configuration.md#sumário)

**API**

- [`LOCALES`](https://postext.dev/pt/docs/document-format.md#citações-e-bibliografia), [`STYLES`](https://postext.dev/pt/docs/document-format.md#citações-e-bibliografia), [`buildBundle`](https://postext.dev/pt/docs/configuration.md#diagramar-e-renderizar-um-pacote), [`clearMeasurementCache`](https://postext.dev/pt/docs/configuration.md#cache-de-medidas), [`createCiteprocEngine`](https://postext.dev/pt/docs/document-format.md#citações-e-bibliografia), [`decompressWoff2`](https://postext.dev/pt/docs/configuration.md#provedor-de-fontes-no-navegador-fontsource--woff2), [`registerCitationEngine`](https://postext.dev/pt/docs/document-format.md#citações-e-bibliografia), [`renderPageToCanvas`](https://postext.dev/pt/docs/configuration.md#renderizar-uma-página-como-bitmap), [`renderToPdf`](https://postext.dev/pt/docs/configuration.md#geração-de-pdf)

**Tipos**

- Libre Caslon Text (OFL-1.1), Libre Caslon Display (OFL-1.1), IBM Plex Sans Condensed (OFL-1.1)

## Preparo

### 1 · Um documento por autor

```js
// script.js, linhas 334–337
// A chapter's :::bibliography lists what that document cites; one Markdown file holding all
// three essays would make every list repeat the works of the chapters before it.
const chapters = [front, lowe, okafor, ferrer].map((markdown) => ({ markdown }));
const book = () => buildBundle({ chapters, config: config(), resources: [] });
```

O alcance da [resposta curta](https://postext.dev/pt/cookbook/edited-volume-chapter-bibliographies.md#a-resposta-curta) é o de um documento. `buildBundle` diagrama os quatro documentos como um só livro, então os números de página, os números de capítulo e o sumário seguem em sequência, enquanto cada `:::bibliography` reúne as citações do seu próprio arquivo. As referências ficam onde o autor as escreveu: uma chave definida em qualquer capítulo vale para o livro inteiro, então uma única entrada compartilhada bastaria, mas capítulos autônomos podem ser trocados ou reordenados sem quebrar a lista de outro ensaio.

### 2 · A autoria é um atributo do título

```js
// script.js, linhas 59–65
// # The Compositor's Day {author="Margaret Lowe" short="The Compositor's Day"}
const byline = text('byline', '{attr.author}', { fontFamily: TEXT, italic: true,
  fontSize: pt(12), color: col('ink'), align: 'left' }, below('title', 4));
const versoAuthor = head('verso-author', '{attr.author}', 'even',
  at('page', 'top-left', MARGIN.outer + 8, 13)); // in the running head
const tocAuthor = { enabled: true, attr: 'author', fontFamily: TEXT, fontSize: pt(9.5),
  color: col('muted') }; // a line under each title in the contents (italic by default)
```

O título de cada ensaio leva `author="…"` e um título curto, `short="…"`, para o cabeço. A abertura imprime o autor sob o título, o cabeço da página par nomeia o autor do ensaio a que a página pertence, e o sumário imprime o nome numa linha sob cada entrada. Nada nas páginas iniciais do livro lista os autores duas vezes.

### 3 · A abertura

```js
// script.js, linhas 69–78
const opener = { enabled: true, minHeight: mm(48), slot: { elements: [
  text('kicker', t({ en: 'Chapter {number}', es: 'Capítulo {number}' }), { ...label,
    fontSize: pt(8.5), letterSpacing: pt(1.7), color: col('accent') },
  at('container', 'top-left', 0, 4)),
  text('title', '{titleText}', { fontFamily: DISPLAY, fontSize: pt(28), lineHeight: 1.08,
    color: col('ink'), align: 'left', overflow: 'wrap' }, below('kicker', 3, { width: 'fill' })),
  byline,
  { kind: 'rule', id: 'rule', direction: 'horizontal', thickness: pt(1.2), color: col('accent'),
    placement: { ...below('byline', 6), size: { width: mm(16) } } },
] } };
```

Antetítulo, título e autoria se empilham a partir do alto da mancha, cada um ancorado abaixo do anterior, de modo que um título de duas linhas, como o do capítulo 3, empurra a autoria e o fio para baixo junto com ele. A reserva de 48 mm comporta um título de duas linhas, e o texto começa na mesma linha da grade em todos os capítulos.

### 4 · Cabeços para um livro de muitos autores

```js
// script.js, linhas 82–96
function head(id, content, parity, placement, look = {}) { // hoisted: the byline uses it
  return { ...text(id, content, { ...label, fontWeight: 500, fontSize: pt(7.5),
    letterSpacing: pt(1.1), color: col('muted'), ...look }, placement), parity, pages: 'body' };
}
const folio = { fontWeight: 600, color: col('ink') };
const header = { elements: [
  head('verso-folio', '{pageNumber}', 'even', at('page', 'top-left', MARGIN.outer, 13), folio),
  versoAuthor,
  head('recto-title', '{attr.short}', 'odd', at('page', 'top-right', -(MARGIN.outer + 8), 13),
    { align: 'right' }),
  head('recto-folio', '{pageNumber}', 'odd', at('page', 'top-right', -MARGIN.outer, 13),
    { ...folio, align: 'right' }),
] };
const footer = { elements: [{ ...head('drop-folio', '{pageNumber}', 'all',
  at('container', 'top', 0, 9), { ...folio, align: 'center' }), pages: 'opener' }] };
```

Uma coletânea nomeia o autor na página par e o capítulo na ímpar, onde uma monografia imprimiria o título do livro e o do capítulo. Os cabeços são filtrados para `pages: 'body'`, então as aberturas levam só um fólio no pé.

### 5 · As páginas iniciais

```js
// script.js, linhas 100–130
const bare = { numbered: false, toc: false, header: { elements: [] }, footer: { elements: [] } };
const cover = { enabled: true, slot: { elements: [
  { kind: 'box', id: 'field', style: { backgroundColor: col('accent') },
    placement: { ...at('bleed', 'top-left'), size: { width: 'fill', height: mm(150) } } },
  text('title', '{titleText}', { fontFamily: DISPLAY, fontSize: pt(58), lineHeight: 1,
    color: col('paper'), align: 'left', overflow: 'wrap' },
  { ...at('page', 'top-left', MARGIN.inner, 64), size: { width: mm(118) } }),
  text('subtitle', '{subtitle}', { fontFamily: TEXT, italic: true, fontSize: pt(15),
    color: col('paper'), align: 'left' }, below('title', 5)),
  text('editors', '{attr.editors}', { ...label, fontSize: pt(9), letterSpacing: pt(1.8),
    color: col('accent') }, at('page', 'top-left', MARGIN.inner, 162)),
  text('contributors', '{attr.contributors}', { fontFamily: TEXT, italic: true, fontSize: pt(12),
    color: col('ink'), align: 'left' }, below('editors', 3)),
  text('imprint', '{attr.imprint}', { ...label, fontWeight: 500, fontSize: pt(7.5),
    letterSpacing: pt(1.5), color: col('muted') }, at('page', 'bottom-left', MARGIN.inner, -16)),
] } };
const contentsOpener = { enabled: true, minHeight: mm(40), slot: { elements: [
  text('kicker', '{title}', { ...label, fontSize: pt(8.5), letterSpacing: pt(1.7),
    color: col('accent') }, at('container', 'top-left', 0, 4)),
  text('title', '{titleText}', { fontFamily: DISPLAY, fontSize: pt(28), color: col('ink'),
    align: 'left' }, below('kicker', 3)),
] } };
const contents = {
  levels: [{ level: 1, fontFamily: TEXT, fontSize: pt(12.5), lineHeight: pt(LEAD),
    numberFontFamily: LABEL, numberFontSize: pt(10), numberFontWeight: 600,
    numberColor: col('accent'), numberWidth: mm(6), numberGap: mm(3), marginBottom: pt(LEAD) }],
  pageNumber: { fontFamily: LABEL, fontSize: pt(9), fontWeight: 600, color: col('ink'),
    width: mm(7) },
  leader: { char: '. ', gap: mm(2) },
  subtitle: tocAuthor,
};
```

A folha de rosto e o sumário são dois títulos sem número no primeiro documento, sem cabeços e sem entrada no sumário. Os designs deles leem `{title}` e `{subtitle}` do frontmatter, e os organizadores e autores, dos atributos do próprio título.

## A receita completa

Um único arquivo, composto a partir da pasta da receita com o texto de exemplo e o kit comum das Receitas já incluídos; ele monta a própria página. Para executá-lo, coloque-o em um `<script type="module">` de uma página vazia ou cole-o no painel JS de um pen novo do CodePen (como módulo). Ele importa o postext do esm.sh, então não há nada para instalar nem compilar.

- Pasta da receita: https://github.com/drnachio/postext/tree/main/cookbook/edited-volume-chapter-bibliographies

### script.js

```js
// ═══ Postext Cookbook · Nº 098 · An edited volume with a bibliography per chapter ═════
// https://postext.dev/en/cookbook/edited-volume-chapter-bibliographies
// Code: MIT · Text: original (CC BY 4.0) · Pictures: none
// Fonts: Libre Caslon Text & Display, IBM Plex Sans Condensed (OFL 1.1) · Needs postext ≥ 1.12.1
// Three essays by three contributors, each a Markdown document of its own with its own
// BibTeX block, laid out by buildBundle as one volume: every chapter closes on its own list.
import {
  buildBundle, renderPageToCanvas, clearMeasurementCache, registerCitationEngine,
} from 'https://esm.sh/postext';
import { renderToPdf, decompressWoff2 } from 'https://esm.sh/postext-pdf';
import { createCiteprocEngine, STYLES, LOCALES } from 'https://esm.sh/postext-citeproc';

const LANG = 'en'; // @lang: the language of the sample document ('en' | 'es')
const RECIPE = 'edited-volume-chapter-bibliographies';

// ─── 1 · Design ─────────────────────────────────────────────────────────────
// #region palette: printer's red on a warm paper, the rest in ink
const palette = {
  ink: '#211c19', // text: a warm near-black
  accent: '#8e2b1f', // printer's red: the cover field, kickers, the references heading
  rule: '#cdbfb2', // hairlines
  muted: '#6b5f57', // running heads, the contents' contributors, the colophon
  paper: '#fcfaf6', // the page, and the type on the red field
};
const col = (id) => ({ hex: palette[id], model: 'hex', paletteId: id });
const colorPalette = Object.entries({ ...palette, 'main-color': palette.accent })
  .map(([id, hex]) => ({ id, name: id, value: { hex, model: 'hex' } }));
// #endregion
const TEXT = 'Libre Caslon Text', DISPLAY = 'Libre Caslon Display';
const LABEL = 'IBM Plex Sans Condensed';
const MARGIN = { top: 23, bottom: 22, inner: 20, outer: 18 }; // mm, mirrored
const LEAD = 13.8; // body leading in pt: the baseline grid
const label = { fontFamily: LABEL, fontWeight: 600, textTransform: 'uppercase', align: 'left' };
const at = (to, edge, x = 0, y = 0) => ({ anchor: { to, edge }, offset: { x: mm(x), y: mm(y) } });
const below = (id, y, size) => ({ ...at(`#${id}`, 'below', 0, y), ...(size && { size }) });
const text = (id, content, look, placement) => ({ kind: 'text', id, content, ...look, placement });

// #region answer: one list per chapter: scope 'chapter' over a book of separate documents
// Citations are [@key] in the text; each contributor's BibTeX goes in a :::references block
// in their own chapter. Register the engine once, before the first build.
registerCitationEngine(createCiteprocEngine({ styles: STYLES, locales: LOCALES }));
const citations = {
  style: 'chicago-author-date', // the humanities' author-date: (Eisenstein 1979)
  bibliography: {
    // 'chapter': a :::bibliography lists the works its own document cites, so a work two
    // contributors cite appears in both lists. 'book' (the default) would print one list,
    // after the last chapter. The scope is per document, not per H1: each essay must be a
    // document of its own in buildBundle (see the chapters region).
    scope: 'chapter',
    title: '', // no bold title paragraph: each chapter has its own ## References heading
    fontSize: em(0.9), lineHeight: pt(12.4), hangingIndent: mm(5), entrySpacing: pt(2.6),
  },
};
// Numbering and disambiguation still see the whole book: two Smiths of 2001 in different
// chapters would print 2001a and 2001b, as one bibliography would.
// #endregion

// #region byline: the contributor, from the heading, in three places
// # The Compositor's Day {author="Margaret Lowe" short="The Compositor's Day"}
const byline = text('byline', '{attr.author}', { fontFamily: TEXT, italic: true,
  fontSize: pt(12), color: col('ink'), align: 'left' }, below('title', 4));
const versoAuthor = head('verso-author', '{attr.author}', 'even',
  at('page', 'top-left', MARGIN.outer + 8, 13)); // in the running head
const tocAuthor = { enabled: true, attr: 'author', fontFamily: TEXT, fontSize: pt(9.5),
  color: col('muted') }; // a line under each title in the contents (italic by default)
// #endregion

// #region opener: kicker, title and byline over a short red rule, sunk 48 mm
const opener = { enabled: true, minHeight: mm(48), slot: { elements: [
  text('kicker', t({ en: 'Chapter {number}', es: 'Capítulo {number}' }), { ...label,
    fontSize: pt(8.5), letterSpacing: pt(1.7), color: col('accent') },
  at('container', 'top-left', 0, 4)),
  text('title', '{titleText}', { fontFamily: DISPLAY, fontSize: pt(28), lineHeight: 1.08,
    color: col('ink'), align: 'left', overflow: 'wrap' }, below('kicker', 3, { width: 'fill' })),
  byline,
  { kind: 'rule', id: 'rule', direction: 'horizontal', thickness: pt(1.2), color: col('accent'),
    placement: { ...below('byline', 6), size: { width: mm(16) } } },
] } };
// #endregion

// #region running-heads: contributor on the verso, short title on the recto, folios outside
function head(id, content, parity, placement, look = {}) { // hoisted: the byline uses it
  return { ...text(id, content, { ...label, fontWeight: 500, fontSize: pt(7.5),
    letterSpacing: pt(1.1), color: col('muted'), ...look }, placement), parity, pages: 'body' };
}
const folio = { fontWeight: 600, color: col('ink') };
const header = { elements: [
  head('verso-folio', '{pageNumber}', 'even', at('page', 'top-left', MARGIN.outer, 13), folio),
  versoAuthor,
  head('recto-title', '{attr.short}', 'odd', at('page', 'top-right', -(MARGIN.outer + 8), 13),
    { align: 'right' }),
  head('recto-folio', '{pageNumber}', 'odd', at('page', 'top-right', -MARGIN.outer, 13),
    { ...folio, align: 'right' }),
] };
const footer = { elements: [{ ...head('drop-folio', '{pageNumber}', 'all',
  at('container', 'top', 0, 9), { ...folio, align: 'center' }), pages: 'opener' }] };
// #endregion

// #region front: the title page on a red field, and the contents
const bare = { numbered: false, toc: false, header: { elements: [] }, footer: { elements: [] } };
const cover = { enabled: true, slot: { elements: [
  { kind: 'box', id: 'field', style: { backgroundColor: col('accent') },
    placement: { ...at('bleed', 'top-left'), size: { width: 'fill', height: mm(150) } } },
  text('title', '{titleText}', { fontFamily: DISPLAY, fontSize: pt(58), lineHeight: 1,
    color: col('paper'), align: 'left', overflow: 'wrap' },
  { ...at('page', 'top-left', MARGIN.inner, 64), size: { width: mm(118) } }),
  text('subtitle', '{subtitle}', { fontFamily: TEXT, italic: true, fontSize: pt(15),
    color: col('paper'), align: 'left' }, below('title', 5)),
  text('editors', '{attr.editors}', { ...label, fontSize: pt(9), letterSpacing: pt(1.8),
    color: col('accent') }, at('page', 'top-left', MARGIN.inner, 162)),
  text('contributors', '{attr.contributors}', { fontFamily: TEXT, italic: true, fontSize: pt(12),
    color: col('ink'), align: 'left' }, below('editors', 3)),
  text('imprint', '{attr.imprint}', { ...label, fontWeight: 500, fontSize: pt(7.5),
    letterSpacing: pt(1.5), color: col('muted') }, at('page', 'bottom-left', MARGIN.inner, -16)),
] } };
const contentsOpener = { enabled: true, minHeight: mm(40), slot: { elements: [
  text('kicker', '{title}', { ...label, fontSize: pt(8.5), letterSpacing: pt(1.7),
    color: col('accent') }, at('container', 'top-left', 0, 4)),
  text('title', '{titleText}', { fontFamily: DISPLAY, fontSize: pt(28), color: col('ink'),
    align: 'left' }, below('kicker', 3)),
] } };
const contents = {
  levels: [{ level: 1, fontFamily: TEXT, fontSize: pt(12.5), lineHeight: pt(LEAD),
    numberFontFamily: LABEL, numberFontSize: pt(10), numberFontWeight: 600,
    numberColor: col('accent'), numberWidth: mm(6), numberGap: mm(3), marginBottom: pt(LEAD) }],
  pageNumber: { fontFamily: LABEL, fontSize: pt(9), fontWeight: 600, color: col('ink'),
    width: mm(7) },
  leader: { char: '. ', gap: mm(2) },
  subtitle: tocAuthor,
};
// #endregion

const config = () => ({ // a factory: the engine caches resolved configs per object
  locale: t({ en: 'en-us', es: 'es' }),
  colorPalette,
  citations,
  page: { sizePreset: 'custom', width: mm(155), height: mm(235), dpi: 150,
    backgroundColor: col('paper'), margins: { top: mm(MARGIN.top), bottom: mm(MARGIN.bottom),
      left: mm(MARGIN.inner), right: mm(MARGIN.outer), mirror: true } },
  layout: { layoutType: 'single' },
  bodyText: { fontFamily: TEXT, fontSize: pt(9.6), lineHeight: pt(LEAD), color: col('ink'),
    boldColor: col('ink'), italicColor: col('ink'), referenceColor: col('ink'),
    textAlign: 'justify', firstLineIndent: mm(4.5), indentAfterHeading: false,
    hyphenation: { enabled: true }, optimalLineBreaking: true, maxWordSpacing: 1.7,
    avoidWidows: true, avoidOrphans: true, avoidRunts: true },
  headings: { fontFamily: DISPLAY, fontWeight: 400, color: col('ink'),
    // A page that ends short may open at most one extra line above a subhead.
    balancing: { maxLinesPerHeading: 1 }, levels: [
    // Restated: any headings object drops the H1 break (gotcha: headings-drop-h1-break).
    // 'any': an essay opens on the next page, recto or verso, as in most edited volumes.
    { level: 1, numberingTemplate: '{1}', marginBottom: pt(0),
      breakBefore: { enabled: true, parity: 'any' }, advancedDesign: opener },
    { level: 2, fontFamily: TEXT, italic: true, fontSize: pt(11), lineHeight: pt(LEAD * 1.5),
      numberingTemplate: '', marginTop: pt(LEAD * 0.5), marginBottom: pt(0) },
  ] },
  headingStyles: [
    { id: 'cover', ...bare, span: 'page', advancedDesign: cover },
    { id: 'contents', ...bare, advancedDesign: contentsOpener },
    // The references heading: the label face in red, out of the contents.
    { id: 'references', toc: false, fontFamily: LABEL, fontWeight: 600, italic: false,
      fontSize: pt(8.5),
      letterSpacing: pt(1.7), textTransform: 'uppercase', color: col('accent'),
      lineHeight: pt(LEAD * 2), marginTop: pt(LEAD), marginBottom: pt(0) },
  ],
  toc: contents,
  calloutStyles: [{ id: 'colophon', placement: 'bottom', backgroundEnabled: false,
    stripe: { enabled: true, side: 'top', width: pt(0.5), color: col('rule') },
    padding: { top: mm(2.5), right: pt(0), bottom: pt(0), left: pt(0) }, marginBottom: pt(0),
    body: { fontFamily: LABEL, fontSize: pt(7.5), lineHeight: pt(10.5), color: col('muted'),
      textAlign: 'left', firstLineIndent: pt(0) } }],
  header, footer,
});

// ─── 2 · Content ────────────────────────────────────────────────────────────
const front = String.raw`---
title: "The Working Page"
subtitle: "Essays on Printing, Type and Reading"
---

# The Working Page {style="cover" editors="Edited by Helen Ashby and Tomás Ribera" contributors="Margaret Lowe · Daniel Okafor · Lucía Ferrer" imprint="Quire Editions · Edinburgh · 2026"}

# Contents {style="contents"}

:::toc

:::callout{type="colophon"}
Set in Libre Caslon Text, Libre Caslon Display and IBM Plex Sans Condensed (SIL OFL). Text: original, CC BY 4.0. The volume, its editors and its contributors are fictional; the works they cite are real.
:::
`; // title page and contents (content.<lang>.md)
const lowe = String.raw`# The Compositor’s Day {author="Margaret Lowe" short="The Compositor’s Day"}

Every page printed by hand passed through a compositor before it reached the press. He stood at a pair of cases, the capitals in the upper one and the small letters in the lower, read a few words of his copy and picked the sorts one at a time into the composing stick in his left hand. When the stick was full he slid the lines onto a galley; when there were lines enough for a page he tied them up with cord and set the page aside until the whole forme could be imposed and locked into its chase. Joseph Moxon described the routine in his *Mechanick Exercises* of 1683–84, the first full manual of printing in English, and most of what bibliographers later wrote about the compositor starts from his account [@gaskell1972].

The work was paid by the piece. A compositor was credited with the number of ens he set, and his speed, his spelling and his care decided what the reader received. That is why the compositor matters to anyone who edits an early printed text: between the author’s manuscript and the printed sheet stood a man with his own habits, working against the clock, who could misread a word, run short of a letter or change the spelling to make a line fit.

## Reading the evidence of the type

The type itself keeps a record of this work. A sort with a nicked serif or a broken stem prints the same flaw wherever it is used, and once the page has been printed the compositor distributes the type back into the case, so the damaged letter turns up again a few pages later. Charlton Hinman followed hundreds of such letters through the Shakespeare First Folio of 1623 and worked out the order in which its pages were set, which compositor set them and how the work moved between the cases [@hinman1963]. His method rested on patience and a Hinman collator, but its premise was simple: type is a finite stock, and its movements can be traced.

Spelling gave a second kind of evidence. One compositor preferred *doe* and *goe*, another *do* and *go*; one set a colon where his partner set a comma. Where the copy did not dictate a form, the compositor’s preference showed through, and a page set by one man reads differently from a page set by another. Bibliographers assembled such preferences into profiles and used them to assign pages and to weigh the authority of a reading [@gaskell1972].

## Printers of the mind

The weakness of these methods lay in what they assumed about the printing house. Analyses of type recurrence often supposed that a shop worked through one book at a time, a compositor setting the pages in order and a press printing each forme as soon as it was ready. D. F. McKenzie tested that picture against the records of Cambridge University Press for the years 1696 to 1712, which survive in unusual detail, and found that it did not hold [@mckenzie1969]. Several books were in production at once. Compositors moved from one job to another as copy arrived; pressmen printed sheets of different books in the same week; work stopped and restarted as paper, money or the author’s revisions allowed.

McKenzie’s conclusion was that bibliographers had built their arguments on “printers of the mind”, an orderly workshop that existed in their reasoning and not in the archive. A pattern found in the type could be explained by more than one sequence of work, and a single sequence could not be inferred from it without outside evidence. His essay did not end the study of compositors, but it changed its tone: inferences now came with the conditions under which they held.

## What the compositor made

The compositor also produced something larger than any single page. Because the same setting of type printed every copy of a sheet, an edition of several hundred copies carried the same text, page for page, to readers who would never meet. Elizabeth Eisenstein made this repetition the centre of her account of early modern Europe: the identical copy, she argued, allowed scholars in different cities to compare the same tables, maps and texts, to correct them in later editions and to build on one another’s work [@eisenstein1979]. The second essay in this volume returns to her argument and to the objections it met.

Yet the copies of an edition were never quite identical. Errors were often caught while a sheet was on the press, and the forme was unlocked and corrected without the sheets already printed being thrown away, so that corrected and uncorrected states were bound up together in the same edition [@gaskell1972]. Hinman found such press variants throughout the Folio [@hinman1963]. The compositor’s day, in other words, made both the stability that Eisenstein described and the small instabilities that bibliographers spend their careers collating.

## References {style="references"}

:::bibliography

:::references{format=bibtex}
@book{gaskell1972,
  author = {Gaskell, Philip}, title = {A New Introduction to Bibliography},
  publisher = {Clarendon Press}, address = {Oxford}, year = 1972}
@book{hinman1963,
  author = {Hinman, Charlton},
  title = {The Printing and Proof-Reading of the First Folio of Shakespeare},
  publisher = {Clarendon Press}, address = {Oxford}, year = 1963}
@article{mckenzie1969,
  author = {McKenzie, D. F.},
  title = {Printers of the Mind: Some Notes on Bibliographical Theories and Printing-House Practices},
  journal = {Studies in Bibliography}, volume = 22, pages = {1--75}, year = 1969}
@book{eisenstein1979,
  author = {Eisenstein, Elizabeth L.},
  title = {The Printing Press as an Agent of Change: Communications and Cultural Transformations in Early-Modern Europe},
  publisher = {Cambridge University Press}, address = {Cambridge}, year = 1979}
:::
`; // content.lowe.<lang>.md: chapter 1, and so on
const okafor = String.raw`# What Fixity Meant {author="Daniel Okafor" short="What Fixity Meant"}

Few books in the history of the book have been argued with as long as Elizabeth Eisenstein’s. *The Printing Press as an Agent of Change* appeared in two volumes in 1979 and proposed that the shift from script to print was itself a cause of the Renaissance revival of learning, of the Reformation and of the new science of the seventeenth century [@eisenstein1979]. Her case rested on a few features that print had and manuscript did not: dissemination in hundreds of copies at once, standardisation of text and image, and above all what she called typographical fixity, the capacity of an edition to preserve a text unchanged and to let it be corrected and improved in the next.

The thesis was large, and its reception divided along a familiar line. Historians of ideas found in it an explanation of why scholarship became cumulative after 1500. Historians of printing pointed to the variety of what presses actually produced, from error-filled almanacs to pirated editions, and asked whether fixity was a property of print or a result that some printers achieved some of the time.

## Credit and piracy

Adrian Johns gave the second answer its fullest form [@johns1998]. Studying the London book trade of the seventeenth century, he found that readers had good reason to distrust what they bought. Editions were reprinted without permission, attributed to authors who had not written them, or issued with the wrong date and imprint. The Stationers’ Company kept a register of titles to settle disputes among its members, but the register protected the trade’s own arrangements rather than the author’s text. A reader who wanted to know whether a printed book was what it claimed to be had to rely on the reputation of the printer and the bookseller, on the people who vouched for the edition, and on the conventions of the shop where it was sold.

Fixity, in Johns’s account, was therefore something made. It took the work of authors who watched over their proofs, of booksellers who guarded their names, and of institutions such as the Royal Society, which licensed and supervised the books it sponsored. His most cited example is the Astronomer Royal, John Flamsteed, who saw his observations printed in 1712 in an edition he had not approved and spent years trying to recover and suppress it. Where Eisenstein saw a feature of the technology, Johns saw a set of practices that had to be learned, and that could fail.

## Circuits and models

The debate between the two positions is easier to follow with a map of what a book passes through. Robert Darnton drew one in 1982: a communications circuit that runs from the author to the publisher, the printers, the shippers, the booksellers and the readers, and back to the author, with each stage shaped by economic, political and intellectual conditions [@darnton1982]. The model placed the history of books among the people who handled them, and many studies of the 1980s worked through it stage by stage.

Thomas Adams and Nicolas Barker objected that Darnton’s circuit described the trade and lost sight of the object. They proposed a model built around the book itself and the events in its life: publication, manufacture, distribution, reception and survival [@adams1993]. The difference matters to the argument about fixity. In Darnton’s circuit, fixity belongs to the relations between printers, sellers and readers; in Adams and Barker’s model, it is also a question of which copies survived, where, and in what state.

## The form of the text

D. F. McKenzie widened the question further in his Panizzi lectures, published in 1986 [@mckenzie1986]. Bibliography, he argued, should study texts as recorded forms and the processes of their transmission, including their production and their reception, and it should treat the form of a text as part of its meaning. His example was William Congreve, whose plays changed character when they were reset for the collected *Works* of 1710: the new layout divided the scenes differently, marked entrances in a new way and invited a different kind of reading.

From McKenzie’s position the quarrel over fixity looks less like a quarrel. An edition can fix the words of a text and still change how it reads; a reprint can keep the meaning and lose the form that carried it. Eisenstein described what the press made possible, and Johns described what it took to make that possibility hold [@eisenstein1979; @johns1998]. Both are histories of the same pages, written from different ends of the circuit.

## References {style="references"}

:::bibliography

:::references{format=bibtex}
@book{eisenstein1979,
  author = {Eisenstein, Elizabeth L.},
  title = {The Printing Press as an Agent of Change: Communications and Cultural Transformations in Early-Modern Europe},
  publisher = {Cambridge University Press}, address = {Cambridge}, year = 1979}
@book{johns1998,
  author = {Johns, Adrian}, title = {The Nature of the Book: Print and Knowledge in the Making},
  publisher = {University of Chicago Press}, address = {Chicago}, year = 1998}
@article{darnton1982,
  author = {Darnton, Robert}, title = {What Is the History of Books?},
  journal = {Daedalus}, volume = 111, number = 3, pages = {65--83}, year = 1982}
@incollection{adams1993,
  author = {Adams, Thomas R. and Barker, Nicolas},
  title = {A New Model for the Study of the Book},
  booktitle = {A Potencie of Life: Books in Society}, editor = {Barker, Nicolas},
  publisher = {British Library}, address = {London}, pages = {5--43}, year = 1993}
@book{mckenzie1986,
  author = {McKenzie, D. F.}, title = {Bibliography and the Sociology of Texts},
  series = {The Panizzi Lectures}, publisher = {British Library}, address = {London},
  year = 1986}
:::
`;
const ferrer = String.raw`# Punches, Matrices and the Name Garamond {author="Lucía Ferrer" short="Punches and Matrices"}

Before a compositor could set a page, someone had to make the letters he picked from the case. Printing spread quickly: Lucien Febvre and Henri-Jean Martin estimated that fifteen to twenty million copies of books had been printed in Europe before 1500 [@febvre1976]. Every one of those copies was printed from type cast in a mould, and every typeface began as a set of steel punches cut by hand at the size the reader would see.

The sequence of work is well documented, though the hand skills it required have mostly been lost [@carter1969]. The punchcutter shaped the end of a steel bar into the reversed form of a letter, filing and engraving it and checking it against smoke proofs. The enclosed spaces of the letter, the counters of *a*, *e* or *o*, were usually struck into the punch with a counterpunch, which let him repeat the same counter in several letters of the fount. Fred Smeijers, who has cut punches himself, argues that the counterpunch explains much of the consistency of sixteenth-century faces: the shapes were related because they were made with the same tools [@smeijers1996].

## From punch to sort

The hardened punch was driven into a bar of copper to make a matrix. The matrix had to be justified, filed so that the letter sat at the right depth and position, and then fitted into a hand mould, an adjustable box of steel and wood into which the caster poured an alloy of lead, tin and antimony. Each pour gave one sort, and the finished type, rubbed and dressed, was sold to printers by weight [@gaskell1972].

Punches were the founder’s capital. They could be used for decades, lent, inherited or sold, and a set of strikes from them allowed another foundry to cast the same face. This is why the faces of a few French punchcutters of the mid-sixteenth century spread across Europe within a generation.

## Whose letters

It also made attribution difficult. A face appears in a printer’s book long after it was cut, under the printer’s name and not the cutter’s. Harry Carter’s survey of early typography set out the evidence available to sort these questions: specimen sheets, inventories, contracts and the books themselves [@carter1969]. Hendrik Vervliet spent decades applying it to the French Renaissance, comparing faces letter by letter across hundreds of books, and his catalogues redistributed many types long credited to Claude Garamont among his contemporaries, Robert Granjon and Pierre Haultin among them [@vervliet2008].

The name Garamond had a modern history of its own. When foundries in the early twentieth century revived “Garamond” for machine composition, several of them took as their model types that had been cut not by Garamont but by Jean Jannon, a printer at Sedan, some sixty years after Garamont’s death. Beatrice Warde pointed this out in 1926. The revivals kept the name, and many digital faces still carry it.

## What the reader sees

None of this is visible on the page as a reader meets it. The reader judges a book by how easily it reads. The bibliographer sees, in the same page, the trace of a punchcutter’s files, the wear of a matrix and the habits of the caster who justified it. Early printers bought their type by size names, pica, english, long primer, and judged it as the reader did, by the page it made [@gaskell1972]. The history of type begins in steel, but it was always written for that page.

## References {style="references"}

:::bibliography

:::references{format=bibtex}
@book{febvre1976,
  author = {Febvre, Lucien and Martin, Henri-Jean},
  title = {The Coming of the Book: The Impact of Printing, 1450--1800},
  translator = {Gerard, David}, publisher = {NLB}, address = {London}, year = 1976}
@book{carter1969,
  author = {Carter, Harry}, title = {A View of Early Typography up to about 1600},
  publisher = {Clarendon Press}, address = {Oxford}, year = 1969}
@book{smeijers1996,
  author = {Smeijers, Fred},
  title = {Counterpunch: Making Type in the Sixteenth Century, Designing Typefaces Now},
  publisher = {Hyphen Press}, address = {London}, year = 1996}
@book{gaskell1972,
  author = {Gaskell, Philip}, title = {A New Introduction to Bibliography},
  publisher = {Clarendon Press}, address = {Oxford}, year = 1972}
@book{vervliet2008,
  author = {Vervliet, Hendrik D. L.},
  title = {The Palaeotypography of the French Renaissance: Selected Papers on Sixteenth-Century Typefaces},
  publisher = {Brill}, address = {Leiden}, year = 2008}
:::
`;
// #region chapters: one document per contributor, each with its own references
// A chapter's :::bibliography lists what that document cites; one Markdown file holding all
// three essays would make every list repeat the works of the chapters before it.
const chapters = [front, lowe, okafor, ferrer].map((markdown) => ({ markdown }));
const book = () => buildBundle({ chapters, config: config(), resources: [] });
// #endregion

// ─── 3 · Fonts ──────────────────────────────────────────────────────────────
const FONTS = { // text, display and label faces (gotcha: fonts-first)
  'Libre Caslon Text': ['400', '400i', '700'],
  'Libre Caslon Display': ['400'],
  'IBM Plex Sans Condensed': ['400', '500', '600'],
};

// ─── 4 · Build & show ───────────────────────────────────────────────────────
const all = chapters.map((chapter) => chapter.markdown).join('\n');
await loadFonts(FONTS, all);
const docs = await buildWithFonts(book, all); // one VDTDocument per Markdown document
showPages(docs, { title: t({ en: 'The Working Page', es: 'La página en obra' }) });
offerPdf(() => renderToPdf(docs, { fontProvider: fontsourceProvider }), `${RECIPE}.pdf`);

// ─── Kit ── helpers shared by every Cookbook recipe · postext.dev/cookbook ─────

// ─── Kit · core v1 ── the same in every recipe · postext.dev/cookbook
function mm(value) { return { value, unit: 'mm' }; }
function pt(value) { return { value, unit: 'pt' }; }
function em(value) { return { value, unit: 'em' }; }
/** The sample language's string: t({ en: 'Figure', es: 'Figura' }). */
function t(strings) { return strings[LANG] ?? Object.values(strings)[0]; }
/** A file in this recipe's assets folder, served from the Postext repo by jsDelivr. */
function asset(file) { return `https://cdn.jsdelivr.net/gh/drnachio/postext@main/cookbook/${RECIPE}/assets/${file}`; }

// ─── Kit · fonts v2 ── the same in every recipe · postext.dev/cookbook
// Postext measures with the loaded faces and caches the widths: load every face
// before the first build, from Fontsource, the files the PDF embeds too.

/** faces = { 'Family Name': ['400', '400i', '700'] }. `text` is the sample:
 *  č ł † α χ also load latin-ext and greek files (kitSubsetsFor). With
 *  `optional`, a face Fontsource does not ship is skipped instead of failing.
 *  Resolves to the number of faces added. */
async function loadFonts(faces, text = '', { optional = false } = {}) {
  kitStatus('Loading fonts…');
  const ranges = {
    latin: 'U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,'
      + 'U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD',
    'latin-ext': 'U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,'
      + 'U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF',
    greek: 'U+0370-03FF',
  };
  const jobs = [];
  let added = 0;
  for (const [family, specs] of Object.entries(faces)) {
    const id = fontsourceId(family);
    const todo = [...new Set(specs)].map((spec) => [parseInt(spec, 10), spec.endsWith('i') ? 'italic' : 'normal'])
      .filter(([weight, style]) => !hasFace(family, weight, style)); // before any await
    const meta = optional || /[^\0-ÿ]/u.test(text) ? await fontsourceMeta(family) : null;
    const subsets = ['latin', ...kitSubsetsFor(text, meta)];
    for (const [weight, style] of todo) {
      if (optional && !(meta?.weights.includes(weight) && meta.styles.includes(style))) continue;
      for (const subset of subsets) {
        const url = `https://cdn.jsdelivr.net/npm/@fontsource/${id}@5/files/${id}-${subset}-${weight}-${style}.woff2`;
        const face = new FontFace(family, `url(${url}) format('woff2')`,
          { weight: String(weight), style, unicodeRange: ranges[subset] });
        jobs.push(face.load().then((ready) => { document.fonts.add(ready); added++; }, () => {
          if (subset === 'latin' && !optional) throw new Error(`Fontsource has no ${family} ${weight} ${style}`);
        }));
      }
    }
  }
  await Promise.all(jobs).catch((error) => { kitFail(error); throw error; });
  return added;
}

/** Runs `build` and loads any face the pages use that FONTS missed (a regular
 *  one with a warning), then clears the measurement cache and builds again. */
async function buildWithFonts(build, text = '') {
  const tried = new Set();
  for (let round = 0; round < 3; round++) {
    kitStatus('Laying out…');
    await new Promise(requestAnimationFrame);          // let the status paint first
    const result = await Promise.resolve().then(build).catch((error) => { kitFail(error); throw error; });
    const wanted = { base: {}, variants: {} };
    for (const { font, base } of [result].flat().flatMap(fontStringsOf)) {
      const { family, weight, style } = parseFont(font);
      const key = `${family}|${weight}|${style}`;
      if (tried.has(key) || hasFace(family, weight, style)) continue;
      tried.add(key);
      (wanted[base ? 'base' : 'variants'][family] ??= []).push(`${weight}${style === 'italic' ? 'i' : ''}`);
    }
    if (Object.keys(wanted.base).length) {
      console.warn(`[cookbook] FONTS does not list ${JSON.stringify(wanted.base)}: loading them.`);
    }
    const added = await loadFonts(wanted.base, text) + await loadFonts(wanted.variants, text, { optional: true });
    if (added === 0) return result;
    clearMeasurementCache();
  }
  throw new Error('The fonts did not settle after three builds.');
}

/** Every font string of the layout; `base` marks a block's own face. */
function fontStringsOf(doc) {
  const found = new Map();
  const walk = (node) => {
    if (!node || typeof node !== 'object') return;
    if (Array.isArray(node)) { node.forEach(walk); return; }
    for (const [key, value] of Object.entries(node)) {
      if (typeof value === 'string' && /fontString$/i.test(key)) {
        found.set(value, found.get(value) || key === 'fontString');
      } else if (value && typeof value === 'object') walk(value);
    }
  };
  walk(doc.pages);
  walk(doc.blocks);
  return [...found].map(([font, base]) => ({ font, base }));
}

/** '700 37.5px Open Sans' / 'italic 400 13px "Source Serif 4"' → { family, weight, style }.
 *  A string with no weight ('95.8px Young Serif', from a design text) is 400. */
function parseFont(font) {
  const m = /^(?:(italic|oblique)\s+)?(?:small-caps\s+)?(?:(\d+|bold|normal)\s+)?[\d.]+px\s+(.+)$/.exec(font.trim());
  if (!m) throw new Error(`Unexpected font string: ${font}`);
  const weight = m[2] === 'bold' ? 700 : !m[2] || m[2] === 'normal' ? 400 : Number(m[2]);
  return { family: m[3].replace(/^["']|["']$/g, ''), weight, style: m[1] ? 'italic' : 'normal' };
}

/** A loaded FontFace covers this family, weight and style (fonts.check() would
 *  also say yes for families nobody declared). */
function hasFace(family, weight, style) {
  for (const face of document.fonts) {
    if (face.status !== 'loaded' || face.style !== style) continue;
    if (face.family.replace(/^["']|["']$/g, '') !== family) continue;
    const [low, high = low] = face.weight.split(' ').map(Number);
    if (weight >= low && weight <= high) return true;
  }
  return false;
}

/** The files beyond latin `text` needs that `meta`'s family ships. */
function kitSubsetsFor(text, meta) {
  return [[/[Ā-˿ᴀ-ᶿḀ-ỿ†ℓⱠ-Ɀ꜠-ꟿ]/u, 'latin-ext'], [/[Ͱ-Ͽ]/u, 'greek']]
    .filter(([re, x]) => re.test(text) && meta?.subsets?.includes(x)).map(([, x]) => x);
}

/** Fontsource's id for a family: 'Source Serif 4' → 'source-serif-4'. */
function fontsourceId(family) { return family.toLowerCase().replace(/\s+/g, '-'); }

/** The family's Fontsource metadata (weights, styles, subsets), or null. */
function fontsourceMeta(family) {
  fontsourceMeta.cache ??= new Map();
  const id = fontsourceId(family);
  if (!fontsourceMeta.cache.has(id)) {
    fontsourceMeta.cache.set(id, fetch(`https://api.fontsource.org/v1/fonts/${id}`)
      .then((res) => (res.ok ? res.json() : null), () => null));
  }
  return fontsourceMeta.cache.get(id);
}

// ─── Kit · viewer v1 ── the same in every recipe · postext.dev/cookbook
/** The pages as spreads on a dark desk, page 1 alone, then verso | recto,
 *  each painted when it scrolls near. */
function showPages(docs, { title, width = 460 } = {}) {
  const root = viewer(title);
  const pages = [docs].flat().flatMap((doc) =>
    doc.pages.map((page) => ({ doc, page, n: (doc.pageIndexOffset ?? 0) + page.index })));
  const spreads = [];
  let verso = null;
  for (const p of pages) {
    if (p.n % 2 === 1) { if (verso) spreads.push([verso, null]); verso = p; }
    else { spreads.push([verso, p]); verso = null; }
  }
  if (verso) spreads.push([verso, null]);
  const density = Math.min(window.devicePixelRatio || 1, 2);
  showPages.painter?.disconnect();
  const painter = new IntersectionObserver((entries) => {
    for (const { isIntersecting, target } of entries) {
      if (!isIntersecting) continue;
      painter.unobserve(target);
      const { doc, page } = target.postext;
      renderPageToCanvas(page, doc, target, { scale: (width * density) / page.width });
    }
  }, { rootMargin: '800px' });
  showPages.painter = painter;
  root.replaceChildren(...spreads.map((pair) => {
    const spread = document.createElement('div');
    spread.className = 'pt-spread';
    for (const p of pair) {
      const figure = document.createElement('figure');
      if (p) {
        const label = p.page.pageLabel || String(p.n + 1);
        const canvas = document.createElement('canvas');
        canvas.postext = p;
        canvas.style.aspectRatio = `${p.page.width} / ${p.page.height}`;
        canvas.setAttribute('role', 'img');
        canvas.setAttribute('aria-label', `Page ${label}`);
        const folio = document.createElement('figcaption');
        folio.textContent = label;
        figure.append(canvas, folio);
        painter.observe(canvas);
      } else figure.className = 'pt-blank';
      spread.append(figure);
    }
    return spread;
  }));
  kitStatus(`${pages.length} ${pages.length === 1 ? 'page' : 'pages'}`);
  document.documentElement.dataset.postext = 'ready';
  return pages.length;
}

/** The desk, the bar and the error reporting, created once. */
function viewer(title) {
  if (!document.getElementById('pt-kit')) {
    document.head.insertAdjacentHTML('beforeend', `<style id="pt-kit">
      :root { color-scheme: dark; }
      body { margin: 0; background: #0e1014; color: #b9bcc4; font: 13px/1.45 system-ui, sans-serif; }
      #pt-bar { position: sticky; top: 0; z-index: 1; display: flex; flex-wrap: wrap; align-items: center;
        gap: 6px 16px; padding: 10px 16px; background: rgb(14 16 20 / .92); backdrop-filter: blur(6px);
        border-bottom: 1px solid #23262d; }
      #pt-bar strong { color: #f4f1ea; font-weight: 600; }
      #pt-actions { display: flex; gap: 12px; margin-left: auto; }
      #pt-actions a, #pt-actions button { color: #d8a21a; font: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
      #pages { display: grid; justify-items: center; gap: 48px; padding: 32px 16px 72px; }
      .pt-spread { display: flex; }
      .pt-spread figure { margin: 0; width: min(460px, 44vw); }
      .pt-spread canvas { display: block; width: 100%; background: #fff;
        box-shadow: 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figure:first-child canvas { box-shadow: inset -14px 0 14px -14px rgb(0 0 0 / .18), 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figcaption { margin-top: 10px; text-align: center; font: 600 10px/1 system-ui, sans-serif;
        letter-spacing: .18em; text-transform: uppercase; color: #6c7079; }
      .pt-blank { visibility: hidden; }
      @media (max-width: 760px) {
        .pt-spread { flex-direction: column; gap: 32px; }
        .pt-spread figure { width: min(460px, 92vw); }
        .pt-blank { display: none; }
      }
    </style>`);
    document.body.insertAdjacentHTML('afterbegin',
      '<header id="pt-bar"><strong id="pt-title"></strong><span id="pt-status" role="status"></span><span id="pt-actions"></span></header>');
    document.getElementById('pt-title').textContent = document.title || 'Postext';
    addEventListener('error', (event) => kitFail(event.error ?? event.message));
    addEventListener('unhandledrejection', (event) => kitFail(event.reason));
  }
  if (title) document.getElementById('pt-title').textContent = title;
  return document.getElementById('pages')
    ?? document.body.appendChild(Object.assign(document.createElement('main'), { id: 'pages' }));
}

function kitStatus(text) {
  viewer();
  document.getElementById('pt-status').textContent = text;
}

function kitFail(error) {
  document.documentElement.dataset.postext = 'error';
  kitStatus(`Error: ${error?.message ?? error}`);
}

// ─── Kit · pdf v2 ── the same in every recipe that exports a PDF
/** The Fontsource files the screen used, as TrueType: the nearest weight the
 *  family ships, upright if it has no italic; latin, then what the face's
 *  letters need (kitSubsetsFor). */
async function fontsourceProvider(family, weight, style, request) {
  const id = fontsourceId(family);
  const meta = await fontsourceMeta(family);
  const weights = meta?.weights?.length ? meta.weights : [400, 700];
  const w = weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a));
  const s = style === 'italic' && meta && !meta.styles.includes('italic') ? 'normal' : style;
  const text = String.fromCodePoint(...(request?.codePoints ?? []));
  const more = kitSubsetsFor(text, meta);
  const files = await Promise.all(['latin', ...more].map(async (subset) => {
    const res = await fetch(`https://cdn.jsdelivr.net/npm/@fontsource/${id}@5/files/${id}-${subset}-${w}-${s}.woff2`);
    if (!res.ok) throw new Error(`Fontsource has no ${family} ${w} ${s} ${subset}`);
    return decompressWoff2(new Uint8Array(await res.arrayBuffer()));
  }));
  return files.length === 1 ? files[0] : files;
}

/** A "Build the PDF" button; then "Open the PDF" (a new tab: CodePen's frame
 *  shows no PDFs) and a download link. */
function offerPdf(makePdf, filename) {
  viewer();
  const button = Object.assign(document.createElement('button'), { type: 'button', textContent: 'Build the PDF' });
  button.dataset.postextPdf = filename;
  button.addEventListener('click', async () => {
    button.disabled = true;
    button.textContent = 'Building the PDF…';
    try {
      const bytes = await makePdf();
      const url = URL.createObjectURL(new Blob([bytes], { type: 'application/pdf' }));
      const size = `${Math.max(1, Math.round(bytes.length / 1024))} KB`;
      button.replaceWith(
        Object.assign(document.createElement('a'), { href: url, target: '_blank', rel: 'noopener', textContent: 'Open the PDF ↗' }),
        Object.assign(document.createElement('a'), { href: url, download: filename, textContent: `Download ${filename} · ${size}` }));
    } catch (error) {
      button.disabled = false;
      button.textContent = 'Build the PDF';
      kitFail(error);
    }
  });
  document.getElementById('pt-actions').append(button);
}

// ─── /Kit ───────────────────────────────────────────────────────────────────────
```

## Variações

### Uma lista para o volume inteiro

Algumas editoras reúnem todas as obras numa única bibliografia no fim. Mude o alcance e tire os três títulos `## References`; a lista passa a vir depois do último capítulo.

```diff
-    scope: 'chapter',
-    title: '', // nenhum parágrafo de título em negrito: cada capítulo tem o seu próprio título ## References
+    scope: 'book',
+    title: 'Bibliography',
```

### Cite em APA

Um volume de ciências sociais muda o estilo e mais nada.

```diff
-  style: 'chicago-author-date', // o autor-data das humanidades: (Eisenstein 1979)
+  style: 'apa',
```

## Erros comuns

- **Uma chave definida duas vezes mantém a primeira entrada, sem aviso.** As referências valem para o livro inteiro: uma chave escrita em dois capítulos mantém a primeira definição, e a segunda é ignorada sem aviso. Em um livro de vários autores, use um prefixo nas chaves de cada colaborador.
- **Qualquer objeto headings desativa a quebra de página do H1.** Por padrão, um H1 salta para uma página ímpar (always-odd), mas passar qualquer objeto headings redefine esse padrão, então os capítulos ficam emendados e span: 'page' não faz nada. Declare de novo headings.levels[0].breakBefore: { enabled: true, parity } em toda configuração.
- **buildBundle não passa metadados entre capítulos; {totalPages} é por capítulo.** buildBundle não passa metadados de um capítulo para o seguinte: {title}, {author} e os demais vêm só do frontmatter do próprio capítulo, então todo capítulo sem frontmatter os imprime vazios (e o Sandbox descarta o frontmatter de todos os capítulos depois do primeiro), e {totalPages} conta as páginas de cada capítulo. Escreva o título do livro literalmente nos cabeços.
- **Valores de atributo: sem { ou }; aspas simples se tiver ".** Um valor de atributo termina na chave de fechamento, por isso não pode conter { nem }. Um valor que contém aspas duplas vai entre aspas simples; o cifrão não causa problema.
- **Um estilo de título herda a quebra de página do seu nível.** Uma entrada de headingStyles recebe do seu nível de título todos os campos que não define, inclusive breakBefore. Um sumário ou um colofão com estilo sobre um H1 depois de um :::pagebreak herda a paridade 'odd' e cai depois de uma página em branco. Dê a esse estilo breakBefore: { enabled: false }.
- **Carregue todas as fontes antes do layout.** O motor de layout mede o texto com as fontes que o navegador carregou e guarda as larguras em cache, então uma fonte que chega depois da primeira composição deixa quebras de linha erradas e um PDF que não corresponde mais à tela. Carregue antes todos os pesos e estilos e chame clearMeasurementCache() antes de recompor quando alguma chegar atrasada.
- **Coloque entre aspas cada valor do frontmatter.** O YAML lê title: 1984 como número e uma data como objeto Date, e valores que não são strings saem vazios nos placeholders e deixam o PDF sem título. Coloque cada valor entre aspas: title: "1984".
- **A configuração fica em cache pela identidade: crie um objeto novo.** O motor guarda em cache as configurações resolvidas pela identidade do objeto, então alterar uma configuração no próprio objeto e compor de novo reaproveita o resultado antigo. Crie um objeto novo a cada composição; por isso a configuração de uma receita é uma função, config().

- `scope: 'chapter'` lista o que o documento cita antes do `:::bibliography`, não o que a sua seção H1 cita. Com todos os ensaios num único arquivo Markdown, a segunda lista repete as obras do primeiro ensaio e a terceira repete as dos dois.
- No livro inteiro vale a primeira definição de cada chave. Se dois autores usarem `smith2001` para obras diferentes, o ensaio posterior cita sem aviso o livro do autor anterior: ponha um prefixo nas chaves de cada autor, ou confira as listas com os originais.
- A desambiguação é calculada para o livro inteiro. Duas obras diferentes de Smith de 2001 em capítulos diferentes podem sair como 2001a e 2001b, mesmo quando a lista de um capítulo contém só uma delas.

## Créditos

- Receita: Ignacio Ferro ([@drnachio](https://github.com/drnachio))
- Tipos: Libre Caslon Text (OFL-1.1), Libre Caslon Display (OFL-1.1), IBM Plex Sans Condensed (OFL-1.1)
- Código: MIT · Conteúdo de exemplo: CC-BY-4.0

## Relacionadas

- [Nº 087 · Um capítulo de tese citado em APA 7](https://postext.dev/pt/cookbook/apa-thesis-with-bibtex.md): Um capítulo de tese de doutorado cujas citações [@key, p. 33] saem em APA 7 pelo citeproc-js, com a lista de referências montada a partir de um bloco BibTeX. · Nível 2 (Intermediário) · Artigos e trabalhos acadêmicos, Relatórios
- [Nº 030 · Antologia com assinaturas de autor](https://postext.dev/pt/cookbook/anthology-with-bylines.md): Três ensaios sobre caminhar cujos títulos levam autor, ano e revista: a abertura imprime os três; os cabeços das páginas pares e o sumário, só o autor. · Nível 2 (Intermediário) · Ficção, teatro e prosa literária
- [Nº 007 · Um livro feito de capítulos separados](https://postext.dev/pt/cookbook/book-from-chapters.md): buildBundle junta cinco arquivos Markdown num livro: cada capítulo abre em página ímpar, e páginas, capítulos e figuras seguem numerados de arquivo em arquivo. · Nível 3 (Avançado) · Manuais, guias e obras de referência