stumbo · Jul 17, 2026 · Jul 22, 2026 · Oct 15, 2026 · Oct 16, 2026 · Oct 16, 2026
diff --git a/.github/workflows/gh-pages.yml b/.github/workflows/gh-pages.yml
@@ -62,11 +62,15 @@ defaults:
         shell: bash
 
 env:
-  HUGO_VERSION: 0.155.3
+  # ----------------------------------------------------------------------------
+  # Specify the deployment environment:  staging or production
+  HUGO_ENVIRONMENT: ${{ vars.HUGO_ENVIRONMENT || 'staging' }}
+  HUGO_VERSION: 0.164.0
 
 jobs:
   # ----------------------------------------------------------------------------
-  # Validate that README.md references the correct Hugo version.
+  # Validate that pinned Hugo version references stay in sync
+  # (README.md, package.json, config/_default/module.yaml).
   # Only runs on push/pull_request, not scheduled runs.
   #
   validate-docs:
@@ -77,26 +81,44 @@ jobs:
 
       - name: Check Hugo version consistency
         run: |
-          echo "Checking README.md for Hugo version $HUGO_VERSION"
-          
+          echo "Checking Hugo version consistency for $HUGO_VERSION"
+
           # Check badge
           if ! grep -q "badge/Hugo-${HUGO_VERSION}" README.md; then
             echo "::error::README.md badge does not reference Hugo version $HUGO_VERSION"
             FAILED=1
           fi
 
-          # Check download URL
-          if ! grep -q "hugo_extended_${HUGO_VERSION}_linux-amd64.deb" README.md; then
-            echo "::error::README.md download URL does not reference Hugo version $HUGO_VERSION"
+          # Check install instructions reference the pinned version.
+          # Accepts either a literal URL (hugo_extended_0.164.0_...)
+          # or the parameterized form (VER=0.164.0 + hugo_extended_${VER}_...).
+          if grep -q "hugo_extended_${HUGO_VERSION}_linux-amd64.deb" README.md; then
+            :
+          elif grep -q "VER=${HUGO_VERSION}" README.md && grep -q 'hugo_extended_${VER}_linux-amd64.deb' README.md; then
+            :
+          else
+            echo "::error::README.md install instructions do not reference Hugo version $HUGO_VERSION"
+            FAILED=1
+          fi
+
+          # Check npm wrapper stays on the pinned version (strict pin)
+          if ! grep -q "\"hugo-extended\": \"\\^${HUGO_VERSION}\"" package.json; then
+            echo "::error::package.json hugo-extended does not reference Hugo version $HUGO_VERSION (expected \"^$HUGO_VERSION\")"
+            FAILED=1
+          fi
+
+          # Check Hugo module minimum matches the pinned version
+          if ! grep -q "min: \"${HUGO_VERSION}\"" config/_default/module.yaml; then
+            echo "::error::config/_default/module.yaml hugoVersion.min does not reference Hugo version $HUGO_VERSION"
             FAILED=1
           fi
 
           if [ "$FAILED" = "1" ]; then
-            echo "Update README.md to use Hugo version $HUGO_VERSION"
+            echo "Update README.md, package.json, and config/_default/module.yaml to use Hugo version $HUGO_VERSION"
             exit 1
           fi
 
-          echo "README.md Hugo version references are consistent"
+          echo "Hugo version references are consistent"
 
   # ----------------------------------------------------------------------------
   # Expose the Hugo version from the workflow environment as a job output.

diff --git a/.gitignore b/.gitignore
@@ -15,8 +15,12 @@ _site
 public/
 tests/public_test/
 node_modules/
+# Generated by "hugo mod npm pack" (see README "Node dependencies")
+packages/hugoautogen/
 _gen/
 .hugo_build.lock
+# Locally downloaded Hugo Debian packages (see README "Installing Hugo")
+*.deb
 .coverage
 tests/__pycache__/
 _vendor/

diff --git a/README.md b/README.md
@@ -2,7 +2,7 @@
 
 [![GitHub Pages Deploy](https://github.com/Interlisp/Interlisp.github.io/actions/workflows/gh-pages.yml/badge.svg)](https://github.com/Interlisp/Interlisp.github.io/actions/workflows/gh-pages.yml)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)
-[![Hugo](https://img.shields.io/badge/Hugo-0.155.3-ff4088?logo=hugo)](https://gohugo.io/)
+[![Hugo](https://img.shields.io/badge/Hugo-0.164.0-ff4088?logo=hugo)](https://gohugo.io/)
 [![Docsy](https://img.shields.io/badge/Theme-Docsy-blue)](https://www.docsy.dev/)
 
 The documentation repository for <https://interlisp.org>, the restoration
@@ -65,18 +65,18 @@ Before working with this repository, ensure you have the following installed:
 
 | Tool | Version | Purpose |
 |------|---------|--------|
-| [Hugo Extended](https://gohugo.io/installation/) | v0.145.0+ | Static site generator |
+| [Hugo Extended](https://gohugo.io/installation/) | v0.160.1+ (CI pins v0.164.0) | Static site generator |
 | [Go](https://go.dev/doc/install) | 1.24+ | Required for Hugo modules |
-| [Node.js & npm](https://nodejs.org/) | Latest LTS | PostCSS and autoprefixer |
+| [Node.js & npm](https://nodejs.org/) | v22+ (LTS 24) | Theme npm dependencies (Bootstrap, Font Awesome) |
 | [jq](https://jqlang.github.io/jq/) | Latest | Bibliography JSON processing |
 | curl, wget | System default | Script downloads |
 
 **Verify installations:**
 
 ```bash
-hugo version      # Should show "extended" and v0.145.0+
+hugo version      # Should show "extended" and v0.160.1+
 go version        # Should show 1.24+
-node --version    # Should show v18+ or later
+node --version    # Should show v22+ or later
 jq --version      # Any recent version
 ```
 
@@ -160,42 +160,56 @@ Local testing of updates requires running Hugo locally.
 
 Instructions for installing Hugo on various operating systems are at: [Installing Hugo](https://gohugo.io/getting-started/installing). **Interlisp uses the extended version of Hugo.**
 
-For Ubuntu:
+For Ubuntu (pinned extended edition, matches CI `HUGO_VERSION`):
 
 ```bash
-wget https://github.com/gohugoio/hugo/releases/download/v0.155.3/hugo_extended_0.155.3_linux-amd64.deb
-
-sudo dpkg -i hugo_extended_0.155.3_linux-amd64.deb
+VER=0.164.0
+DEB="hugo_extended_${VER}_linux-amd64.deb"
+wget --retry-connrefused --waitretry=5 --read-timeout=30 --timeout=30 --tries=5 \
+  -O "/tmp/${DEB}" "https://github.com/gohugoio/hugo/releases/download/v${VER}/${DEB}"
+wget --retry-connrefused --waitretry=5 --read-timeout=30 --timeout=30 --tries=5 \
+  -O "/tmp/hugo_${VER}_checksums.txt" "https://github.com/gohugoio/hugo/releases/download/v${VER}/hugo_${VER}_checksums.txt"
+( cd /tmp && grep -F " ${DEB}" "hugo_${VER}_checksums.txt" | sha256sum -c - )
+sudo dpkg -i "/tmp/${DEB}"
+rm -f "/tmp/${DEB}" "/tmp/hugo_${VER}_checksums.txt"
 ```
 
 Verify installation:
 
 ```bash
 hugo version
 # Expected output:
-hugo v0.155.3-8a858213b73907e823e2be2b5640a0ce4c04d295+extended linux/amd64 BuildDate=2026-02-08T16:40:42Z VendorInfo=gohugoio
+hugo v0.164.0+extended linux/amd64 BuildDate=...
 
 ```
 
 ### Running the Development Server
 
 1. Ensure bibliography data is available (see [Bibliography Data](#bibliography-data))
 
-2. Start the Hugo development server:
+2. Install the theme's npm dependencies (Bootstrap, Font Awesome). Required — a
+   Docsy 0.16 module build reads them from `node_modules/`. `npm install` also
+   auto-generates the gitignored `packages/hugoautogen` workspace via a
+   `postinstall` hook, so there is no separate step:
+
+```bash
+npm install
+```
+
+3. Start the Hugo development server:
 
 ```bash
 hugo server --cleanDestinationDir  --disableFastRender --renderToMemory
 ```
 
-Hugo will automatically download the Docsy theme and its dependencies as Hugo modules. Expected output:
+Hugo will automatically download the Docsy theme as a Hugo module, and reads
+Bootstrap and Font Awesome from `node_modules/` (installed above). Expected output:
 
 ```bash
 Watching for changes in <project-root>/archetypes, <project-root>/assets/{css,icons,js,scss}, <project-root>/content/en/{history,project,software}, <project-root>/layouts/{_default,_partials,_shortcodes,bibliography,redirect}, <project-root>/package.json, <project-root>/static/{Resources,data,docs,documentation,favicons}
 Watching for config changes in <project-root>/config/_default, <project-root>/config/development, <project-root>/go.mod
 Start building sites … 
-hugo v0.155.3-8a858213b73907e823e2be2b5640a0ce4c04d295+extended linux/amd64 BuildDate=2026-02-08T16:40:42Z VendorInfo=gohugoio
-
-WARN  WARNING: 298 sidebar entries have been truncated. To avoid this, increase `params.ui.sidebar_menu_truncate` to at least 398 (from 100) in your config file. Section: /history/bibliography
+hugo v0.164.0+extended linux/amd64 BuildDate=...
 
                   │  EN  
 ──────────────────┼──────
@@ -286,7 +300,7 @@ The following repository variables control the build and deployment process:
 | Variable | Description | Values | Default |
 |----------|-------------|--------|---------|
 | `HUGO_ENVIRONMENT` | Build environment used by the production workflow | `development`, `staging`, `production` | `production` |
-| `HUGO_VERSION` | Hugo version used in CI/CD | Semantic version (e.g., `0.155.3`) | Set in workflow |
+| `HUGO_VERSION` | Hugo version used in CI/CD | Semantic version (e.g., `0.164.0`) | Set in workflow |
 
 `HUGO_ENVIRONMENT` is resolved in `.github/workflows/gh-pages.yml` and passed
 as the `hugo-environment` input to the shared build workflow.  The staging
@@ -398,22 +412,29 @@ The repository follows the standard [Hugo directory structure](https://gohugo.io
 
 | Module | Version | Purpose |
 |--------|---------|---------|
-| [google/docsy](https://github.com/google/docsy) | v0.14.3 | Technical documentation theme |
-| docsy/dependencies | v0.7.2 | Docsy's required dependencies |
+| [google/docsy/theme](https://github.com/google/docsy) | v0.16.0 | Technical documentation theme |
 
 Hugo modules are automatically downloaded when you run `hugo server` or `hugo build`.
 
 **npm Packages (package.json):**
 
 | Package | Purpose |
 |---------|---------|
-| autoprefixer | Adds vendor prefixes to CSS for browser compatibility |
 | hugo-extended | Hugo binary for npm-based workflows |
-| postcss / postcss-cli | CSS transformation pipeline |
 | jquery | JavaScript library used by some Docsy components |
 | tabpanel | Accessible tab panel widget |
 
-Install npm dependencies with `npm install` (optional for local development).
+The Docsy theme's own npm dependencies (Bootstrap and Font Awesome) are declared
+in `packages/hugoautogen/package.json`, which is **auto-generated and gitignored**.
+A `postinstall` hook runs `hugo mod npm pack` on every `npm install`/`npm ci`, so this
+file — and the Bootstrap/Font Awesome install — is kept up to date automatically; there
+is no need to run the pack step by hand or commit anything under `packages/`. When you
+update Docsy, just run `npm install` and commit the updated `package.json` and
+`package-lock.json`.
+
+Install npm dependencies with `npm install` (or `npm ci`). Since Docsy 0.16 sources Bootstrap
+and Font Awesome from npm, this is **required** (not optional) for both local
+development and CI builds.
 
 ### Search Configuration
 

diff --git a/config/_default/imaging.yaml b/config/_default/imaging.yaml
@@ -4,6 +4,10 @@
 #
 # Configuration information available at:
 # https://gohugo.io/content-management/image-processing/#resampling-filter
+#
+# NOTE: The global `quality` setting was deprecated in Hugo 0.163.0 in favor
+# of per-format settings. It was removed here because its previous value (75)
+# matches Hugo's default. Set per-format `quality` under `imaging.<format>`
+# (e.g. `jpeg`, `webp`) if a non-default value is ever needed.
 resampleFilter: CatmullRom
-quality: 75
 anchor: smart
diff --git a/config/_default/languages.yaml b/config/_default/languages.yaml
@@ -5,11 +5,12 @@
 # See:  https://gohugo.io/content-management/multilingual/
 #
 en:
-  languageName: English
-  languageCode: en-us
+  label: English
+  locale: en-US
   # Weight used for sorting.
   weight: 1
   contentDir: content/en
+  direction: ltr
   params:
     description: "Dedicated to restoring and preserving the Interlisp experience"
 

diff --git a/config/_default/module.yaml b/config/_default/module.yaml
@@ -1,11 +1,9 @@
   proxy: "direct"
   # uncomment line below for temporary local development of module
-  # replacements = "github.com/google/docsy -> ../../docsy"
+  # replacements = "github.com/google/docsy/theme -> ../../docsy/theme"
   hugoVersion:
     extended: true
-    min: "0.155.2"
+    min: "0.164.0"
   imports:
-    - path: "github.com/google/docsy"
+    - path: "github.com/google/docsy/theme"
       disable: false
-    - path: "github.com/google/docsy/dependencies"
-      disable: false
diff --git a/config/_default/params.yaml b/config/_default/params.yaml
@@ -32,6 +32,12 @@ url_latest_version: https://example.com
 # in `markup.yaml`
 prism_syntax_highlighting: false
 
+#  author: site author information (used in RSS feed, etc.)
+#
+author:
+  name: Interlisp.org
+  email: info@interlisp.org
+
 #  copyright:  site copyright information
 #    authors:  text list of authors
 #    from_year:  year in copyright statement

diff --git a/config/staging/hugo.yaml b/config/staging/hugo.yaml
@@ -1,6 +1,6 @@
 baseURL: https://interlisp.github.io/Interlisp.staging/
 
-languageCode: en-us
+locale: en-us
 
 # title
 #  Insert Staging Environment onto every page to make clear

diff --git a/config/testing/hugo.yaml b/config/testing/hugo.yaml
@@ -11,6 +11,10 @@
 # The module.mounts block must re-declare all standard project-level mounts
 # because adding any mount replaces Hugo's defaults for the project.
 # Theme (Docsy) mounts defined within that module are unaffected.
+#
+# Note: the mounts below do not set `lang` — that option was deprecated in Hugo
+# 0.153.0. This is a single-language site, so mounts apply to the default
+# (English) language without it.
 
 baseURL: "http://localhost/"
 
@@ -30,7 +34,6 @@ module:
     # URLs are generated without an /en/ prefix (matching production behavior).
     - source: content/en
       target: content
-      lang: en
     - source: static
       target: static
     - source: layouts
@@ -47,4 +50,3 @@ module:
     # Mount alongside the real bibliography content for the English language.
     - source: tests/fixtures/bibliography
       target: content/history/bibliography
-      lang: en
diff --git a/go.mod b/go.mod
@@ -2,7 +2,4 @@ module github.com/Interlisp/Interlisp.github.io
 
 go 1.24
 
-require (
-	github.com/google/docsy v0.14.3 // indirect
-	github.com/google/docsy/dependencies v0.7.2 // indirect
-)
+require github.com/google/docsy/theme v0.16.0 // indirect
diff --git a/go.sum b/go.sum
@@ -1,11 +1,2 @@
-github.com/FortAwesome/Font-Awesome v0.0.0-20230327165841-0698449d50f2/go.mod h1:IUgezN/MFpCDIlFezw3L8j83oeiIuYoj28Miwr/KUYo=
-github.com/FortAwesome/Font-Awesome v0.0.0-20241216213156-af620534bfc3/go.mod h1:IUgezN/MFpCDIlFezw3L8j83oeiIuYoj28Miwr/KUYo=
-github.com/google/docsy v0.14.2 h1:XJud05ZWCUFgvE9G1KdxhGsDdr7OmWYdnWPxrclIPWE=
-github.com/google/docsy v0.14.2/go.mod h1:1Fj1W1O3esZh7IBQ8XAYtxtg10udBXuGI89+LUQc1AU=
-github.com/google/docsy v0.14.3 h1:4uFgPWTPj4NT79IboVkXGi49LLQadLVfU4WNOfD/s74=
-github.com/google/docsy v0.14.3/go.mod h1:1Fj1W1O3esZh7IBQ8XAYtxtg10udBXuGI89+LUQc1AU=
-github.com/google/docsy/dependencies v0.7.2 h1:+t5ufoADQAj4XneFphz4A+UU0ICAxmNaRHVWtMYXPSI=
-github.com/google/docsy/dependencies v0.7.2/go.mod h1:gihhs5gmgeO+wuoay4FwOzob+jYJVyQbNaQOh788lD4=
-github.com/twbs/bootstrap v4.6.2+incompatible/go.mod h1:fZTSrkpSf0/HkL0IIJzvVspTt1r9zuf7XlZau8kpcY0=
-github.com/twbs/bootstrap v5.2.3+incompatible/go.mod h1:fZTSrkpSf0/HkL0IIJzvVspTt1r9zuf7XlZau8kpcY0=
-github.com/twbs/bootstrap v5.3.8+incompatible/go.mod h1:fZTSrkpSf0/HkL0IIJzvVspTt1r9zuf7XlZau8kpcY0=
+github.com/google/docsy/theme v0.16.0 h1:9uV9qEhk7UpJ8KYbSpTPQlq6htH+8hYskedgGZVnNsU=
+github.com/google/docsy/theme v0.16.0/go.mod h1:NX/JqXCbZBn9Q2Hj7ez9Xeh9z4XcLiwmDYZXhB4RhRM=
diff --git a/layouts/_default/rss.xml b/layouts/_default/rss.xml
@@ -2,11 +2,15 @@
 {{- printf "<?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"yes\"?>" | safeHTML }}
 
 {{- $authorName := "" }}
+{{- $authorEmail := "" }}
 {{- with .Site.Params.author }}
   {{- if reflect.IsMap . }}
     {{- with .name }}
       {{- $authorName = . }}
     {{- end }}
+    {{- with .email }}
+      {{- $authorEmail = . }}
+    {{- end }}
   {{- else }}
     {{- $authorName  = . }}
   {{- end }}
@@ -50,10 +54,10 @@
     <title>Updates from the new Medley Interlisp Project</title>
     <link>{{ .Permalink }}</link>
     <description>Updates from the Medley Interlisp Project</description>
-    <generator>Hugo -- gohugo.io</generator>{{ with .Site.LanguageCode }}
-    <language>{{.}}</language>{{end}}{{ with .Site.Author.email }}
-    <managingEditor>{{.}}{{ with $.Site.Author.name }} ({{.}}){{end}}</managingEditor>{{end}}{{ with .Site.Author.email }}
-    <webMaster>{{.}}{{ with $.Site.Author.name }} ({{.}}){{end}}</webMaster>{{end}}{{ with .Site.Copyright }}
+    <generator>Hugo -- gohugo.io</generator>{{ with .Site.Language.Locale }}
+    <language>{{.}}</language>{{end}}{{ with $authorEmail }}
+    <managingEditor>{{.}}{{ with $authorName }} ({{.}}){{end}}</managingEditor>{{end}}{{ with $authorEmail }}
+    <webMaster>{{.}}{{ with $authorName }} ({{.}}){{end}}</webMaster>{{end}}{{ with .Site.Copyright }}
     <copyright>{{.}}</copyright>{{end}}{{ if not .Date.IsZero }}
     <lastBuildDate>{{ .Date.Format "Mon, 02 Jan 2006 15:04:05 -0700" | safeHTML }}</lastBuildDate>{{ end }}
     {{ with .OutputFormats.Get "RSS" }}
@@ -64,7 +68,7 @@
       <title>{{ .Title }}</title>
       <link>{{ .Permalink }}</link>
       <pubDate>{{ .Date.Format "Mon, 02 Jan 2006 15:04:05 -0700" | safeHTML }}</pubDate>
-      {{ with .Site.Author.email }}<author>{{.}}{{ with $.Site.Author.name }} ({{.}}){{end}}</author>{{end}}
+      {{ with $authorEmail }}<author>{{.}}{{ with $authorName }} ({{.}}){{end}}</author>{{end}}
       <guid>{{ .Permalink }}</guid>
       <description>{{ .Summary | html }}</description>
       {{ range .Params.tags }}

diff --git a/layouts/_partials/page-meta-links.html b/layouts/_partials/page-meta-links.html
@@ -12,10 +12,10 @@
 <div class="td-page-meta ms-2 pb-1 pt-2 mb-0">
 	{{ if $gh_repo -}}
 		{{ $gh_repo_path := printf "%s/content/%s" $gh_branch $pathFormatted -}}
-		{{ if and ($gh_subdir) (.Site.Language.Lang) -}}
-		{{ $gh_repo_path = printf "%s/%s/content/%s/%s" $gh_branch $gh_subdir ($.Site.Language.Lang) $pathFormatted -}}
-		{{ else if .Site.Language.Lang -}}
-		{{ $gh_repo_path = printf "%s/content/%s/%s" $gh_branch ($.Site.Language.Lang) $pathFormatted -}}
+		{{ if and ($gh_subdir) (.Site.Language.Name) -}}
+		{{ $gh_repo_path = printf "%s/%s/content/%s/%s" $gh_branch $gh_subdir ($.Site.Language.Name) $pathFormatted -}}
+		{{ else if .Site.Language.Name -}}
+		{{ $gh_repo_path = printf "%s/content/%s/%s" $gh_branch ($.Site.Language.Name) $pathFormatted -}}
 		{{ else if $gh_subdir -}}
 		{{ $gh_repo_path = printf "%s/%s/content/%s" $gh_branch $gh_subdir $pathFormatted -}}
 	{{ end -}}