diff --git a/.claude/rules/dev-tools/dependency-updates.md b/.claude/rules/dev-tools/dependency-updates.md
new file mode 100644
index 00000000000..3f93ac33054
--- /dev/null
+++ b/.claude/rules/dev-tools/dependency-updates.md
@@ -0,0 +1,10 @@
+---
+description: "Bundled dependency version bumps (Deno, Pandoc, Dart Sass, Typst, esbuild, veraPDF)"
+paths:
+  - "configuration"
+  - "src/command/check/check.ts"
+---
+
+# Bundled Dependency Updates
+
+When updating a bundled binary, follow `dev-docs/upgrade-dependencies.md`. For Pandoc, also follow `dev-docs/update-pandoc-checklist.md`.
diff --git a/.claude/rules/formats/pandoc-templates.md b/.claude/rules/formats/pandoc-templates.md
index 68c8d56e80c..f875c8b922d 100644
--- a/.claude/rules/formats/pandoc-templates.md
+++ b/.claude/rules/formats/pandoc-templates.md
@@ -1,12 +1,19 @@
 ---
 paths:
   - "src/resources/formats/pdf/pandoc/**"
+  - "src/resources/formats/beamer/pandoc/**"
   - "src/resources/formats/typst/pandoc/**"
+  - "src/resources/formats/html/pandoc/**"
+  - "src/resources/formats/revealjs/pandoc/**"
+  - "src/resources/formats/asciidoc/pandoc/**"
   - "package/src/common/update-pandoc.ts"
+  - "dev-docs/update-pandoc-checklist.md"
 ---
 
-# Pandoc Templates (LaTeX & Typst)
+# Pandoc Templates (LaTeX, Typst, HTML, Reveal.js, AsciiDoc)
 
 For how Pandoc's LaTeX templates are copied into Quarto and restructured into a modular form (`latex.template`, `latex.common`, …), see `llm-docs/pandoc-quarto-latex-templates.md`.
 
 For the equivalent Typst template integration (`typst.template`, `template.typst`), see `llm-docs/pandoc-quarto-typst-templates.md`.
+
+When updating Pandoc templates, read `dev-docs/update-pandoc-checklist.md` for the per-format file list, reference-copy maintenance, and filename checks.
diff --git a/.github/actions/README.md b/.github/actions/README.md
new file mode 100644
index 00000000000..2503b1431cb
--- /dev/null
+++ b/.github/actions/README.md
@@ -0,0 +1,10 @@
+# Composite Actions
+
+Reusable steps shared across workflows in this repo. See also `.github/workflows/actions/` for another set of composite actions (historical split, no functional difference).
+
+| Action | Purpose |
+|--------|---------|
+| [`build-dist-tarball`](build-dist-tarball/action.yml) | Builds and uploads a versioned Quarto distribution tarball from the current checkout. |
+| [`cache-typst`](cache-typst/action.yml) | Configures caching for Typst packages. |
+| [`docker`](docker/action.yml) | Builds and pushes a Quarto Docker container to the GitHub Container Registry. |
+| [`merge-extension-tests`](merge-extension-tests/action.yml) | Copies test files from extension subtrees into the main test directories. |
diff --git a/.github/workflows/actions/README.md b/.github/workflows/actions/README.md
new file mode 100644
index 00000000000..991c7b7be0f
--- /dev/null
+++ b/.github/workflows/actions/README.md
@@ -0,0 +1,13 @@
+# Composite Actions
+
+Reusable steps shared across workflows in this repo. See also `.github/actions/` for another set of composite actions (historical split, no functional difference).
+
+| Action | Purpose |
+|--------|---------|
+| [`amplitude`](amplitude/action.yml) | Sends an event to Amplitude. |
+| [`archive`](archive/action.yml) | Archives a dependency binary to S3. |
+| [`keychain`](keychain/action.yml) | Configures a P12 certificate into the keychain for signing. |
+| [`pandoc-override`](pandoc-override/action.yml) | Installs a Pandoc release for smoke tests before S3 archival and selects it through `QUARTO_PANDOC`. |
+| [`prevent-rerun`](prevent-rerun/action.yml) | Fails if the workflow is re-run (`github.run_attempt > 1`). |
+| [`quarto-dev`](quarto-dev/action.yml) | Configures the image for Quarto development (runs `configure.sh`/`.cmd`). |
+| [`sign-files`](sign-files/action.yml) | Installs and configures the environment to sign files. |
diff --git a/.github/workflows/actions/pandoc-override/action.yml b/.github/workflows/actions/pandoc-override/action.yml
new file mode 100644
index 00000000000..e350d4b8702
--- /dev/null
+++ b/.github/workflows/actions/pandoc-override/action.yml
@@ -0,0 +1,48 @@
+name: "Pandoc Override"
+description: "Installs a Pandoc release for smoke tests before S3 archival and selects it through QUARTO_PANDOC. If pandoc-version is empty, Quarto uses the configured binary."
+
+inputs:
+  pandoc-version:
+    description: "Pandoc release tag to install and use instead of the archived/configured version (e.g. 3.10.1). Leave empty to skip."
+    required: false
+    default: ""
+
+runs:
+  using: "composite"
+  steps:
+    - name: Install Pandoc override
+      if: inputs.pandoc-version != ''
+      uses: r-lib/actions/setup-pandoc@v2
+      with:
+        pandoc-version: ${{ inputs.pandoc-version }}
+
+    - name: Point QUARTO_PANDOC at override (Linux, macOS)
+      if: runner.os != 'Windows' && inputs.pandoc-version != ''
+      shell: bash
+      run: echo "QUARTO_PANDOC=$(command -v pandoc)" >> "$GITHUB_ENV"
+
+    - name: Point QUARTO_PANDOC at override (Windows)
+      if: runner.os == 'Windows' && inputs.pandoc-version != ''
+      shell: pwsh
+      run: |
+        "QUARTO_PANDOC=$((Get-Command pandoc).Source)" >> $env:GITHUB_ENV
+
+    # Lets check-versions-no-mismatch.test.ts tell an intentional override
+    # apart from a real bundled-version mismatch. Passed via env so the
+    # dispatch input is never interpolated into the shell script.
+    - name: Record expected Pandoc version for the version-mismatch test
+      if: inputs.pandoc-version != ''
+      shell: bash
+      env:
+        PANDOC_VERSION: ${{ inputs.pandoc-version }}
+      run: echo "QUARTO_TEST_EXPECTED_PANDOC=$PANDOC_VERSION" >> "$GITHUB_ENV"
+
+    - name: Confirm Pandoc override is live (Linux, macOS)
+      if: runner.os != 'Windows' && inputs.pandoc-version != ''
+      shell: bash
+      run: quarto pandoc --version
+
+    - name: Confirm Pandoc override is live (Windows)
+      if: runner.os == 'Windows' && inputs.pandoc-version != ''
+      shell: pwsh
+      run: quarto pandoc --version
diff --git a/.github/workflows/test-smokes.yml b/.github/workflows/test-smokes.yml
index b7a76360212..9db1df1b731 100644
--- a/.github/workflows/test-smokes.yml
+++ b/.github/workflows/test-smokes.yml
@@ -71,6 +71,11 @@ on:
         required: false
         type: string
         default: ""
+      pandoc-override-version:
+        description: "Pandoc release tag to download from GitHub for smoke tests before S3 archival (e.g. 3.10.1). Quarto selects it through QUARTO_PANDOC. Leave empty to use the configured binary."
+        required: false
+        type: string
+        default: ""
 
 # this is required to cleanup julia cache
 permissions:
@@ -504,6 +509,12 @@ jobs:
             echo "QUARTO_TEST_EXPECTED_VERSION=$QUARTO_VERSION_INPUT" >> "$GITHUB_ENV"
           fi
 
+      # Guarded at the step so runs on older refs, which lack this action, never load it.
+      - if: inputs.pandoc-override-version != ''
+        uses: ./.github/workflows/actions/pandoc-override
+        with:
+          pandoc-version: ${{ inputs.pandoc-override-version }}
+
       - name: Install Tinytex
         env:
           GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/dev-docs/update-pandoc-checklist.md b/dev-docs/update-pandoc-checklist.md
index abc4206d779..bd33f84cb5a 100644
--- a/dev-docs/update-pandoc-checklist.md
+++ b/dev-docs/update-pandoc-checklist.md
@@ -1,13 +1,39 @@
 ## Updating the bundled version of Pandoc
 
-Carlos needs to run this:
+Updating Pandoc happens in two phases. Phase 1 (prep) needs no S3 access and can be done by anyone; Phase 2 (archival) is done by whoever holds S3 write credentials, right before merge.
 
-- [ ] Ensure archives are upgraded
-- [ ] Run `AWS_PROFILE=... ./package/src/quarto-bld update-pandoc PANDOC_VERSION`
-- [ ] look at `git diff`, specifically for changes in Pandoc templates, and adjust as needed.
+### Phase 1 - prep (no S3, anyone)
 
-As a reminder, our templates are kept in the same directories as Pandoc's templates, but with different names. `git diff` will show the diff in Pandoc's template; we have to manually patch
-ours. (We can't just use `patch` because the templates have diverged too much)
+Regenerate the reference copies and `src/core/pandoc/format-extension.ts`, port relevant changes to Quarto's templates, and verify rendering. Keep `configuration`'s `export PANDOC=` line at the archived version so `./configure.sh`/`.cmd` continues to work.
+
+Run the template/variant regeneration with `--skip-archive`, pointing `QUARTO_PANDOC` at an executable of the target version:
+
+```bash
+QUARTO_PANDOC=/path/to/pandoc-3.10.1/bin/pandoc \
+  ./package/src/quarto-bld update-pandoc 3.10.1 --skip-archive
+```
+
+`--skip-archive` skips S3 archival, the `configureDependency` download, and the `configuration` rewrite. It still runs `writePandocTemplates` to regenerate the mapped template files and `writeVariants` to regenerate `format-extension.ts`.
+
+`QUARTO_PANDOC` is required: `writeVariants` uses that binary to enumerate formats and extensions. The command checks its version before regenerating files. Review and commit the resulting working-tree diff.
+
+`writePandocTemplates` overwrites the reference copies and mapped Pandoc partials such as `fonts.latex` and `hypersetup.latex`. Port relevant changes to Quarto's templates using the [file list below](#pandoc-templates). Review generated changes to `format-extension.ts` as well. The same review applies to the full Phase 2 run.
+
+To smoke-test rendering before archival, dispatch `.github/workflows/test-smokes.yml` with `pandoc-override-version` set to the new release tag (e.g. `3.10.1`). The workflow downloads Pandoc from GitHub and uses it via `QUARTO_PANDOC` for that run, without S3 access. Limit `buckets` to the relevant smoke-all directories (e.g. `typst`, `latex`, `table`) for a faster run.
+
+For a full-suite run, the action sets `QUARTO_TEST_EXPECTED_PANDOC`. The version check accepts either OK or a strict-mismatch note for the requested version, normalized as in `check.ts`.
+
+### Phase 2 - archival (S3 credential holder, before merge)
+
+Whoever holds S3 write credentials does this last, right before merging:
+
+- [ ] Bump `configuration`'s `export PANDOC=` line and the `Pandoc` entry in `src/command/check/check.ts`'s `versionConstraints` array to the new version (this constraint tracks the bundled version exactly).
+- [ ] Ensure archives are upgraded.
+- [ ] Run `AWS_PROFILE=... ./package/src/quarto-bld update-pandoc PANDOC_VERSION` (without `--skip-archive`) to archive the binary to S3, configure it locally, and regenerate templates/variants.
+- [ ] Review `git diff` for regenerated reference copies, mapped Pandoc partials, and `format-extension.ts`. Port any remaining upstream changes to Quarto's templates and reapply any Quarto changes overwritten in mapped partials.
+- [ ] Run the `create-release.yml` dry-run signing/notarization gate (see `dev-docs/upgrade-dependencies.md`), then merge.
+
+Quarto's templates share directories with the Pandoc reference copies, but use different names. Review the reference-copy diffs and port relevant changes manually; the templates have diverged too much to use `patch`.
 
 ### Pandoc templates
 
@@ -25,6 +51,36 @@ Partials:
 - Ours:
   - src/resources/formats/beamer/pandoc/common.latex
 
+#### pdf / latex
+
+- Pandoc's: src/resources/formats/pdf/pandoc/latex.template
+- Ours: src/resources/formats/pdf/pandoc/template.tex (see `llm-docs/pandoc-quarto-latex-templates.md` for the full partial breakdown, including `latex.common`/`common.latex`)
+
+#### html
+
+- Pandoc's: src/resources/formats/html/pandoc/html.template, src/resources/formats/html/pandoc/html.styles
+- Ours: src/resources/formats/html/pandoc/template.html, src/resources/formats/html/pandoc/styles.html
+
+#### revealjs
+
+- Pandoc's: src/resources/formats/revealjs/pandoc/revealjs.template
+- Ours: src/resources/formats/revealjs/pandoc/template.html
+
+#### asciidoc
+
+- Pandoc's: src/resources/formats/asciidoc/pandoc/asciidoc.template
+- Ours: src/resources/formats/asciidoc/pandoc/template.asciidoc
+
+#### typst
+
+Typst keeps Pandoc's `template.typst` partial under its original name alongside the renamed `typst.template`. See `llm-docs/pandoc-quarto-typst-templates.md` for Quarto's partials.
+
+The files labelled "Pandoc's" are reference copies used to review upstream changes. Rendering uses the corresponding "Ours" files and their partials, such as `tables.tex` and `toc.tex`.
+
+- Regenerate reference copies from upstream with `writePandocTemplates`; apply rendering changes to Quarto's templates and partials.
+- Keep reference copies identical to upstream, including any upstream typos. Manual edits are overwritten on regeneration. Fix upstream bugs in Quarto's templates.
+- List the directory without filtering by extension when checking the files: `*.latex` excludes `latex.common`, which ends in `.common`.
+
 ## Manual steps
 
 - [ ] Update schemas by inspecting [their changelog](https://github.com/jgm/pandoc/blob/main/changelog.md) for new commands, deprecation removals, etc
diff --git a/dev-docs/upgrade-dependencies.md b/dev-docs/upgrade-dependencies.md
index b51f82d1121..718eb98a918 100644
--- a/dev-docs/upgrade-dependencies.md
+++ b/dev-docs/upgrade-dependencies.md
@@ -1,6 +1,8 @@
 Change version numbers in `./configuration` to correspond to new versions.
 
-Update hardcoded version strings in `src/command/check/check.ts` (the `versionConstraints` array in `checkVersions`) so that they match the new versions in `configuration`. The `configuration` file warns about this in a comment, and `tests/smoke/check/check-versions-no-mismatch.test.ts` fails until they match.
+Update hardcoded version strings in `src/command/check/check.ts` (the `versionConstraints` array in `checkVersions`) so that they match the new versions in `configuration`. The `configuration` file warns about this in a comment, and `tests/smoke/check/check-versions-no-mismatch.test.ts` fails until they match. The constraint tracks the bundled version exactly, not a minimum floor.
+
+For Pandoc, follow [update-pandoc-checklist.md](update-pandoc-checklist.md) for template updates and filename conventions, schema and Lua type checks, and CI smoke tests using `QUARTO_PANDOC` before S3 archival.
 
 ## Verify installer signing & notarization before merging (bundled binaries)
 
diff --git a/llm-docs/localization-architecture.md b/llm-docs/localization-architecture.md
index 0fe590714ae..e4d6fe904b9 100644
--- a/llm-docs/localization-architecture.md
+++ b/llm-docs/localization-architecture.md
@@ -16,14 +16,13 @@ key_files:
   - src/resources/filters/modules/authors.lua
   - src/resources/filters/modules/callouts.lua
   - src/resources/filters/layout/meta.lua
-  - src/resources/formats/html/pandoc/html.template
+  - src/resources/formats/html/pandoc/template.html
+  - src/resources/formats/html/pandoc/toc.html
   - src/resources/formats/html/pandoc/title-block.html
   - src/resources/formats/html/templates/title-metadata.html
-  - src/resources/formats/pdf/pandoc/latex.template
   - src/resources/formats/pdf/pandoc/babel-lang.tex
   - src/resources/formats/pdf/pandoc/toc.tex
-  - src/resources/formats/beamer/pandoc/beamer.template
-  - src/resources/formats/typst/pandoc/typst.template
+  - src/resources/formats/beamer/pandoc/toc.tex
   - src/resources/formats/typst/pandoc/quarto/typst-template.typ
   - src/resources/formats/typst/pandoc/quarto/typst-show.typ
   - src/resources/extension-subtrees/orange-book/_extensions/orange-book/typst-show.typ
@@ -151,12 +150,14 @@ These bypass both Pandoc metadata and Lua filters. The string lands directly in
 
 `quarto.*` is an internal namespace. The user-facing override path for localized strings is the top-level `language:` YAML key (resolved by `formatLanguage`, already merged into `options.format.language` before the builder runs). The schema does not advertise `variables.quarto.*` as a user option, but the merge in `generateDefaults` honors a user-set value on collision: it deep-merges via `mergeConfigs` (`src/core/config.ts`) so user-supplied keys win at any nesting depth while all other localized values remain available. For example, a user setting `variables.quarto.language.crossref-ch-prefix: Bouquin` overrides only that one leaf — `$quarto.language.toc-title-document$` still resolves to the localized fallback. (Same helper is used in `src/core/language.ts:formatLanguage` to merge user-supplied `language:` onto `_language.yml` defaults.) A non-object `variables.quarto` (string, number, array) is ignored defensively. New contributors to this file should design around the `language:` path, not around the escape hatch.
 
-From any Pandoc template — built-in (`html.template`, `latex.template`, `typst-template.typ`), extension partial, or custom user template — every localized key is then accessible as:
+From any Pandoc template — built-in (`template.html`, `template.tex`, `typst-template.typ`), extension partial, or custom user template — every localized key is then accessible as:
 
 ```pandoc
 $quarto.language.<key>$
 ```
 
+> **Naming note**: Citations below refer to Quarto's rendering templates: `template.html` (HTML), `template.tex` (LaTeX/PDF and Beamer), and `quarto/typst-template.typ` (Typst). See `dev-docs/update-pandoc-checklist.md` for the corresponding Pandoc reference copies.
+
 For example, `$quarto.language.crossref-ch-prefix$` resolves to `Chapitre` when `lang: fr` is set. Hyphens within the leaf segment are valid Pandoc template-variable syntax (manual: *"Variable names can include letters, numbers, underscores, hyphens, and periods"*).
 
 This is the channel of choice for new template consumers because:
@@ -173,9 +174,9 @@ It does **not** replace 2a — Lua filters still need `param("key")` because Pan
 
 Localization paths used:
 
-- **Document `lang` attribute**: `_language.yml` lookup not involved. `lang:` flows as Pandoc-native metadata, template renders `<html lang="$lang$" xml:lang="$lang$">` (`html.template:2`).
-- **TOC title**: `$toc-title$` resolved via channel 2b. Used in `html.template:60`, `toc.html:3`.
-- **Abstract title**: `$abstract-title$` resolved via 2b. Used in `html.template:51`, `title-block.html:15`.
+- **Document `lang` attribute**: `_language.yml` lookup not involved. `lang:` flows as Pandoc-native metadata, template renders `<html$if(lang)$ lang="$lang$" xml:lang="$lang$"$endif$>` (`template.html:2`).
+- **TOC title**: `$toc-title$` resolved via channel 2b. Used in `toc.html:3`.
+- **Abstract title**: `$abstract-title$` resolved via 2b. Used in `title-block.html:15`.
 - **Title block labels** (`Authors`, `Affiliations`, `Published`, `Modified`, `Doi`, `Abstract`, `Keywords`): `$labels.*$` written into meta by `modules/authors.lua:854-913` (`computeLabels`). Templates: `title-metadata.html:3,4,32,43,52,61,74,83`, `manuscript/title-metadata.html:6,7,37,48,57,66,83,92`.
 - **Crossref text** (`Figure 1.1`, `Table 2.1`): assembled in Lua by `crossref/format.lua` using `title()` / `refPrefix()` which call `param("crossref-<type>-title"/"-prefix")`. Written as inline text directly into the AST. By the time Pandoc renders HTML, the localized prefix is already document content.
 - **Callout titles** (`Tip`, `Note`, etc.): `modules/callouts.lua:15,185` reads `param("callout-<type>-title", default)`, writes into the callout node.
@@ -191,7 +192,7 @@ Three localization paths layered:
 
    Other Lua filters use `metaInjectLatex` for non-language LaTeX customization (`crossref/custom.lua:78`, `layout/meta.lua`, `quarto-post/landscape.lua`, etc. — they inject packages or styling, not localized strings).
 
-3. **Pandoc template `$var$`** — `pdf/pandoc/toc.tex:3` and `pdf/pandoc/latex.template:93-94` use `$toc-title$` to set `\contentsname`. Beamer templates (`beamer/pandoc/beamer.template:146-151`, `beamer/pandoc/toc.tex:3`) likewise.
+3. **Pandoc template `$var$`** — `pdf/pandoc/toc.tex:2-3` uses `$toc-title$` to set `\contentsname`. Beamer's `beamer/pandoc/toc.tex:2-3` does the same.
 
 PDF-side TS code does not read `format.language` directly except `src/format/pdf/format-pdf.ts:242` which registers `"babel-lang"` as a Quarto partial.
 
diff --git a/llm-docs/pandoc-quarto-latex-templates.md b/llm-docs/pandoc-quarto-latex-templates.md
index c75e11f5d9b..31a007ef89b 100644
--- a/llm-docs/pandoc-quarto-latex-templates.md
+++ b/llm-docs/pandoc-quarto-latex-templates.md
@@ -1,3 +1,16 @@
+---
+main_commit: d30cdbb9e
+analyzed_date: 2026-07-23
+key_files:
+  - package/src/common/update-pandoc.ts
+  - src/format/pdf/format-pdf.ts
+  - src/resources/formats/pdf/pandoc/template.tex
+  - src/resources/formats/pdf/pandoc/common.latex
+  - src/resources/formats/pdf/pandoc/pandoc.tex
+  - src/resources/formats/pdf/pandoc/document-metadata.latex
+  - src/resources/formats/beamer/pandoc/template.tex
+---
+
 # Pandoc and Quarto LaTeX Templates
 
 This document describes how Quarto integrates Pandoc's LaTeX templates and transforms them into a modular structure suitable for Quarto's extended functionality.
@@ -13,7 +26,7 @@ The `writePandocTemplates` function in `package/src/common/update-pandoc.ts` han
 
 ### Files Copied
 
-Seven files are copied from Pandoc for LaTeX support:
+The `templateDirFiles` mapping in `update-pandoc.ts` omits `document-metadata.latex`. Check `partialNamesPandoc` in `format-pdf.ts` for the complete list of Pandoc-derived partials.
 
 | Pandoc Source                 | Quarto Destination | Notes                                              |
 | ----------------------------- | ------------------ | -------------------------------------------------- |
@@ -24,6 +37,7 @@ Seven files are copied from Pandoc for LaTeX support:
 | `font-settings.latex`         | (unchanged)        | User font configuration                            |
 | `fonts.latex`                 | (unchanged)        | Font engine detection                              |
 | `passoptions.latex`           | (unchanged)        | Package options passthrough                        |
+| `document-metadata.latex`     | (unchanged)        | PDF standard metadata (PDF/A, PDF/UA, PDF/X); added in Quarto 1.7 following Pandoc 3.6.3 support; **not copied by `update-pandoc.ts`'s current mapping** |
 
 ### Purpose of Each Pandoc File
 
@@ -41,6 +55,8 @@ Seven files are copied from Pandoc for LaTeX support:
 
 **passoptions.latex**: Package options passthrough mechanism for hyperref, xcolor, and xeCJK.
 
+**document-metadata.latex**: Emits a `\DocumentMetadata{...}` block (LuaLaTeX, 2023+ LaTeX) for PDF/A, PDF/UA, and PDF/X standards support, driven by the `pdfstandard` variable. Called first, before `passoptions.latex()`, in the pdf `template.tex`. **Beamer does not use this partial** — its `template.tex` has no `document-metadata.latex()` call, and `format-pdf.ts` filters it out of `beamerPartialNamesPandoc`.
+
 ## 2. Quarto's Modular Template Structure
 
 Quarto breaks the Pandoc templates into a modular structure in `src/resources/formats/pdf/pandoc/`. This allows for:
@@ -68,7 +84,7 @@ Assembles the document by including all partials in order. This is Quarto's main
 
 Quarto maintains two versions of the common preamble:
 
-**latex.common** (264 lines): Pandoc's original, kept as reference. Contains the full common preamble: paragraph formatting, verbatim, highlighting, tables, graphics, strikeout, CSL citations, Babel, page style, tight lists, subfigure support, text direction, natbib/biblatex configuration.
+**latex.common** (265 lines): Pandoc's original, kept as reference. Contains the full common preamble: paragraph formatting, verbatim, highlighting, tables, graphics, strikeout, CSL citations, Babel, page style, tight lists, subfigure support, text direction, natbib/biblatex configuration.
 
 **common.latex** (66 lines): Quarto's shortened version that:
 
@@ -77,6 +93,8 @@ Quarto maintains two versions of the common preamble:
 
 This allows Quarto to selectively override specific parts of the common preamble while maintaining compatibility with Pandoc updates.
 
+Pandoc's `common.latex` is copied as `latex.common`; Quarto maintains its own `common.latex`. See `dev-docs/update-pandoc-checklist.md` for reference-copy maintenance and filename checks.
+
 ### Quarto Partials (\*.tex)
 
 **Document Structure:**
@@ -120,37 +138,38 @@ The `template.tex` orchestrates the full document:
 
 ### Preamble (before `\begin{document}`)
 
-1. `$passoptions.latex()$` - Package options passthrough
-2. `$doc-class.tex()$` - `\documentclass[...]{...}` declaration
-3. (inline) - beamerarticle, xcolor, geometry, amsmath
-4. (inline) - Section numbering configuration
-5. `$fonts.latex()$` - Font engine detection (ifPDFTeX, ifXeTeX, ifLuaTeX)
-6. `$font-settings.latex()$` - User font configuration
-7. `$common.latex()$` - Common preamble setup, which internally calls:
+1. `$document-metadata.latex()$` - `\DocumentMetadata{...}` for PDF/A, PDF/UA, PDF/X (pdf only — beamer's `template.tex` omits this call)
+2. `$passoptions.latex()$` - Package options passthrough
+3. `$doc-class.tex()$` - `\documentclass[...]{...}` declaration
+4. (inline) - beamerarticle, xcolor, geometry, amsmath
+5. (inline) - Section numbering configuration
+6. `$fonts.latex()$` - Font engine detection (ifPDFTeX, ifXeTeX, ifLuaTeX)
+7. `$font-settings.latex()$` - User font configuration
+8. `$common.latex()$` - Common preamble setup, which internally calls:
    - `$pandoc.tex()$` → `$tables.tex()$`, `$graphics.tex()$`, `$citations.tex()$`, `$babel-lang.tex()$`, `$tightlist.tex()$`, `$biblio-config.tex()$`
-8. `$after-header-includes.latex()$` - Bookmark, URL packages
-9. `$hypersetup.latex()$` - Hyperref configuration
-10. `$before-title.tex()$` - Pre-title content
-11. `$title.tex()$` - `\title{}`, `\author{}`, `\date{}`
+9. `$after-header-includes.latex()$` - Bookmark, URL packages
+10. `$hypersetup.latex()$` - Hyperref configuration
+11. `$before-title.tex()$` - Pre-title content
+12. `$title.tex()$` - `\title{}`, `\author{}`, `\date{}`
 
 ### Document Body
 
-12. `\begin{document}`
-13. `$before-body.tex()$` - Frontmatter, `\maketitle`, abstract
-14. (loop) - include-before content
-15. `$toc.tex()$` - Table of contents
-16. (inline) - linestretch, mainmatter
-17. `$body$` - Document content
-18. `$before-bib.tex()$` - Pre-bibliography content
-19. (inline) - backmatter, nocite
-20. `$biblio.tex()$` - Bibliography rendering
-21. (loop) - include-after content
-22. `$after-body.tex()$` - Post-body content
-23. `\end{document}`
+13. `\begin{document}`
+14. `$before-body.tex()$` - Frontmatter, `\maketitle`, abstract
+15. (loop) - include-before content
+16. `$toc.tex()$` - Table of contents
+17. (inline) - linestretch, mainmatter
+18. `$body$` - Document content
+19. `$before-bib.tex()$` - Pre-bibliography content
+20. (inline) - backmatter, nocite
+21. `$biblio.tex()$` - Bibliography rendering
+22. (loop) - include-after content
+23. `$after-body.tex()$` - Post-body content
+24. `\end{document}`
 
 ## 4. TypeScript Configuration
 
-The `pdfFormat` function in `src/format/pdf/format-pdf.ts` (lines 236-284) defines the template configuration:
+The template configuration is defined inline inside `src/format/pdf/format-pdf.ts` (around lines 241-267, in the function that builds the PDF format):
 
 ```typescript
 // Quarto-maintained partials (.tex)
@@ -176,6 +195,7 @@ const partialNamesQuarto: string[] = [
 const partialNamesPandoc: string[] = [
   "after-header-includes",
   "common",
+  "document-metadata",
   "font-settings",
   "fonts",
   "hypersetup",
@@ -188,6 +208,8 @@ The template context maps these to files:
 - Quarto partials: `pandoc/${name}.tex`
 - Pandoc partials: `pandoc/${name}.latex`
 
+Beamer builds its own `beamerPartialNamesPandoc` by filtering `document-metadata` out of `partialNamesPandoc` (`.filter((name) => name !== "document-metadata")`), since beamer's `template.tex` never calls it.
+
 ## 5. Parameter Summary Table
 
 ### Font Parameters (XeTeX/LuaTeX)
diff --git a/llm-docs/pandoc-quarto-typst-templates.md b/llm-docs/pandoc-quarto-typst-templates.md
index c0182dd640c..a94cb9175ed 100644
--- a/llm-docs/pandoc-quarto-typst-templates.md
+++ b/llm-docs/pandoc-quarto-typst-templates.md
@@ -1,3 +1,15 @@
+---
+main_commit: d30cdbb9e
+analyzed_date: 2026-07-23
+key_files:
+  - package/src/common/update-pandoc.ts
+  - src/format/typst/format-typst.ts
+  - src/resources/formats/typst/pandoc/quarto/definitions.typ
+  - src/resources/formats/typst/pandoc/quarto/template.typ
+  - src/resources/formats/typst/pandoc/typst.template
+  - src/resources/formats/typst/pandoc/template.typst
+---
+
 # Pandoc and Quarto Typst Templates
 
 This document describes how Quarto integrates Pandoc's typst templates and transforms them into a more modular structure suitable for Quarto's extended functionality.
@@ -172,9 +184,21 @@ Handles bibliography rendering:
 - Sets bibliography style from CSL file or bibliography style option
 - Renders bibliography from specified files
 
-### typst.template - Reference Copy
+### typst.template and template.typst - Reference Copies
+
+`typst.template` (Pandoc's `default.typst`) and `template.typst` (kept under its original name) are reference copies. `format-typst.ts` uses the `quarto/` template and partials described above for rendering.
+
+During a Pandoc update, review their diffs and port relevant changes to `quarto/definitions.typ` and the other Quarto partials. See `dev-docs/update-pandoc-checklist.md` for the regeneration and reference-copy maintenance procedure.
+
+### Writer-Level Changes vs. Template-Level Changes
+
+Pandoc's Typst writer converts the AST into body markup. Changes to its output can affect rendering regardless of the template used.
+
+For example, Pandoc 3.10.1 changed `HorizontalRule` output from `#horizontalrule` to `#divider()`, a native function added in Typst 0.15. The bundled Typst version is 0.15.1, so this call needs no local definition. Quarto's `quarto/definitions.typ` still defines `horizontalrule` for use by `notes.typ`.
+
+The same release changed definition-list output: descriptions are emitted directly rather than wrapped in `#block[...]`, relying on an external `#set terms(hanging-indent: ...)`. Quarto's `#show terms.item` rule reformats the description in either case. Neither change required a template change for Quarto.
 
-This is the copy of Pandoc's `default.typst`, kept for reference. It is used when rendering without Quarto's template context (e.g., when a user provides a custom template).
+When updating Pandoc, render a document with both versions using `QUARTO_PANDOC` and compare the generated `.typ` body content. Template diffs alone do not show changes in writer output.
 
 ## 3. Parameter Summary Table
 
diff --git a/package/src/common/update-pandoc.ts b/package/src/common/update-pandoc.ts
index 9b99c17ca6a..560394ca343 100644
--- a/package/src/common/update-pandoc.ts
+++ b/package/src/common/update-pandoc.ts
@@ -7,7 +7,7 @@
 import { Command } from "cliffy/command/mod.ts";
 import { join } from "../../../src/deno_ral/path.ts";
 import { ensureDirSync } from "../../../src/deno_ral/fs.ts";
-import { info } from "../../../src/deno_ral/log.ts";
+import { error, info } from "../../../src/deno_ral/log.ts";
 
 import {
   Configuration,
@@ -33,61 +33,134 @@ import {
 
 import * as ld from "../../../src/core/lodash.ts";
 
+import { execProcess } from "../../../src/core/process.ts";
+import { pandocBinaryPath } from "../../../src/core/resources.ts";
+
 export function updatePandoc() {
   return new Command()
     .name("update-pandoc")
     .arguments("<version:string>")
     .description("Updates Pandoc to the specified version")
-    .action(async (_args, version: string) => {
+    .option(
+      "--skip-archive",
+      "Regenerate templates and format-extension.ts without archiving to S3, configuring the binary, or updating configuration. Requires QUARTO_PANDOC to resolve to the requested version.",
+    )
+    // deno-lint-ignore no-explicit-any
+    .action(async (options: any, version: string) => {
       info(`Updating Pandoc to ${version}`);
 
       const configuration = readConfiguration();
+      const skipArchive = !!options.skipArchive;
 
-      // Update the configuration file
-      info("  updating configuration file.");
-      const configFilePath = join(
-        configuration.directoryInfo.root,
-        "configuration",
-      );
-      const configText = Deno.readTextFileSync(configFilePath);
-      const configLines = lines(configText);
-      const outputLines: string[] = [];
-      for (const line of configLines) {
-        if (line.startsWith("export PANDOC=")) {
-          outputLines.push(`export PANDOC=${version}`);
-        } else {
-          outputLines.push(line);
+      if (skipArchive) {
+        // writeVariants() needs the target Pandoc binary to enumerate formats/extensions.
+        const overridePath = Deno.env.get("QUARTO_PANDOC");
+        if (!overridePath) {
+          error(
+            `QUARTO_PANDOC is not set. Set it to a Pandoc ${version} executable ` +
+              "before using --skip-archive.",
+          );
+          throw new Error("QUARTO_PANDOC is not set");
         }
-      }
-      Deno.writeTextFileSync(configFilePath, outputLines.join("\n"));
 
-      const pandocDependency = pandoc(version);
+        // An unresolved QUARTO_PANDOC can fall back to the bundled binary.
+        // Verify the version before generating format-extension.ts.
+        let reported: string | undefined;
+        try {
+          reported = lines(
+            (await execProcess({
+              cmd: pandocBinaryPath(),
+              args: ["--version"],
+              stdout: "piped",
+            })).stdout!,
+          )[0]?.split(" ")[1];
+        } catch (_e) {
+          error(
+            "Could not run the QUARTO_PANDOC binary to verify its version. " +
+              `QUARTO_PANDOC is set to "${overridePath}". Confirm it points at a ` +
+              "runnable Pandoc executable.",
+          );
+          throw new Error("QUARTO_PANDOC binary is not runnable");
+        }
+        if (
+          normalizePandocVersion(reported) !== normalizePandocVersion(version)
+        ) {
+          error(
+            `The Pandoc binary resolved via QUARTO_PANDOC reports version ` +
+              `${reported}, not the requested ${version}. QUARTO_PANDOC is set to ` +
+              `"${overridePath}". An unresolved override can fall back to the ` +
+              `bundled binary. Set QUARTO_PANDOC to a Pandoc ${version} executable ` +
+              "and retry.",
+          );
+          throw new Error("QUARTO_PANDOC does not resolve to the requested version");
+        }
+      } else {
+        info("  updating configuration file.");
+        const configFilePath = join(
+          configuration.directoryInfo.root,
+          "configuration",
+        );
+        const configText = Deno.readTextFileSync(configFilePath);
+        const configLines = lines(configText);
+        const outputLines: string[] = [];
+        for (const line of configLines) {
+          if (line.startsWith("export PANDOC=")) {
+            outputLines.push(`export PANDOC=${version}`);
+          } else {
+            outputLines.push(line);
+          }
+        }
+        Deno.writeTextFileSync(configFilePath, outputLines.join("\n"));
+      }
 
-      // Call archive-bin-deps for this file
       await withWorkingDir(async (workingDir) => {
-        await archiveBinaryDependency(pandocDependency, workingDir);
+        if (!skipArchive) {
+          const pandocDependency = pandoc(version);
 
-        // Configure this version of pandoc
-        await configureDependency(
-          pandocDependency,
-          join(configuration.directoryInfo.bin, "tools"),
-          configuration,
-        );
+          await archiveBinaryDependency(pandocDependency, workingDir);
+
+          await configureDependency(
+            pandocDependency,
+            join(configuration.directoryInfo.bin, "tools"),
+            configuration,
+          );
+        }
 
-        // Generate templates
+        // Templates are downloaded from Pandoc's source archive on GitHub.
         await writePandocTemplates(configuration, version, workingDir);
 
-        // Generate variants
+        // Generate format extensions using the resolved Pandoc binary,
+        // including any QUARTO_PANDOC override.
         await writeVariants(configuration);
       });
 
-      // print the warning to complete the checklist
-      console.log(bgBlack(brightWhite(bold(
-        "\n** Remember to complete the checklist in /dev-docs/update-pandoc-checklist.md! **",
-      ))));
+      if (skipArchive) {
+        console.log(bgBlack(brightWhite(bold(
+          "\n** Templates and src/core/pandoc/format-extension.ts regenerated. **" +
+            "\n** Review `git diff` and port relevant upstream changes to Quarto's templates. **" +
+            "\n** Configuration is unchanged. Complete dev-docs/update-pandoc-checklist.md before merging. **",
+        ))));
+      } else {
+        console.log(bgBlack(brightWhite(bold(
+          "\n** Remember to complete the checklist in /dev-docs/update-pandoc-checklist.md! **",
+        ))));
+      }
     });
 }
 
+// Pad a Pandoc version to at least 3 parts so "3.10" matches "3.10.0".
+// Longer versions keep every part: 3.1.6.1 and 3.1.6.2 are distinct releases.
+function normalizePandocVersion(version: string | undefined): string {
+  if (!version) {
+    return "";
+  }
+  const parts = version.split(".");
+  if (parts.length < 3) {
+    return parts.concat(Array(3 - parts.length).fill("0")).join(".");
+  }
+  return parts.join(".");
+}
+
 // Starting in Pandoc 3, we saw a number of variants that appear to be supported
 // disappear from the --list-extensions command, so for the time being we're just
 // hard adding them here
diff --git a/tests/smoke/check/check-versions-no-mismatch.test.ts b/tests/smoke/check/check-versions-no-mismatch.test.ts
index b080ab19c0e..326eee93ee0 100644
--- a/tests/smoke/check/check-versions-no-mismatch.test.ts
+++ b/tests/smoke/check/check-versions-no-mismatch.test.ts
@@ -5,21 +5,57 @@
 *
 */
 
-import { testQuartoCmd } from "../../test.ts";
+import { testQuartoCmd, type Verify } from "../../test.ts";
 import { printsMessage } from "../../verify.ts";
 
-// If this test fails, it indicates that there is a version mismatch 
-// Check 'src\command\check\check.ts' for the recorded versions, and compare to 'configuration' file
+// For unexpected mismatches, compare versionConstraints in
+// src/command/check/check.ts with configuration.
+
+// QUARTO_TEST_EXPECTED_PANDOC records an intentional override. Accept either
+// OK or a strict-mismatch note for that version, normalized as in check.ts.
+const expectedPandocOverride = Deno.env.get("QUARTO_TEST_EXPECTED_PANDOC");
+
+// Mirrors the padding/truncation check.ts applies before its strict
+// comparison, so a requested "3.10" matches the reported "3.10.0".
+const normalizePandocVersion = (version: string): string => {
+  const parts = version.split(".");
+  if (parts.length > 3) {
+    return parts.slice(0, 3).join(".");
+  }
+  return parts.concat(Array(3 - parts.length).fill("0")).join(".");
+};
+
+const verifies: Verify[] = [
+  printsMessage({
+    level: "INFO",
+    regex: "(Dart Sass|Deno|Typst) version .*does not strictly match",
+    negate: true,
+  }),
+];
+
+if (expectedPandocOverride) {
+  verifies.push(
+    printsMessage({
+      level: "INFO",
+      regex: `Pandoc version ${
+        normalizePandocVersion(expectedPandocOverride).replaceAll(".", "\\.")
+      }(: OK| does not strictly match)`,
+    }),
+  );
+} else {
+  verifies.push(
+    printsMessage({
+      level: "INFO",
+      regex: "Pandoc version .*does not strictly match",
+      negate: true,
+    }),
+  );
+}
+
 testQuartoCmd(
   "check",
   ["versions"],
-  [
-    printsMessage({
-      level: "INFO",
-      regex: "does not strictly match",
-      negate: true  // Verify this message does NOT appear
-    })
-  ],
+  verifies,
   undefined,
-  "check versions --strict should not show version mismatches"
+  "check versions should report expected dependency versions",
 );
diff --git a/tools/runtime-boundary-baseline.json b/tools/runtime-boundary-baseline.json
index cf99f8c67f6..fb072f47d04 100644
--- a/tools/runtime-boundary-baseline.json
+++ b/tools/runtime-boundary-baseline.json
@@ -12,11 +12,11 @@
     "stdImportFiles": 1
   },
   "package/src": {
-    "denoCalls": 240,
+    "denoCalls": 241,
     "stdImportFiles": 3
   },
   "tests": {
-    "denoCalls": 774,
+    "denoCalls": 775,
     "stdImportFiles": 176
   }
 }