diff --git a/README.org b/README.org
index ab323ac..fe9efc1 100644
--- a/README.org
+++ b/README.org
@@ -37,12 +37,13 @@ the section entitled "GNU Free Documentation License".
 :CUSTOM_ID: sec:quick-start
 :END:
 
-Backup the =user-emacs-directory= (defaults often to =~/.emacs.d= on =Linux=,
-=Unix=, or =Darwin=) and execute the commands in listing [[lst:prepare-user-emacs-directory-with-https][prepare the
-=user-emacs-directory= without =ssh= access]] or in listing [[lst:prepare-user-emacs-directory-with-ssh][prepare the
-=user-emacs-directory= with =ssh= access]].  After invoking Emacs interactively
-(in interactive mode, neither in batch mode, nor in server mode), Emacs will ask
-you to install a selected set of packages.  Quit Emacs and invoke Emacs again.
+This setup requires at least Emacs-29.0.60.  Backup the =user-emacs-directory=
+(defaults often to =~/.emacs.d= on =Linux=, =Unix=, or =Darwin=) and execute the
+commands in listing [[lst:prepare-user-emacs-directory-with-https][prepare the =user-emacs-directory= without =ssh= access]] or
+in listing [[lst:prepare-user-emacs-directory-with-ssh][prepare the =user-emacs-directory= with =ssh= access]].  After invoking
+Emacs interactively (in interactive mode, neither in batch mode, nor in server
+mode), Emacs will ask you to install a selected set of packages.  Quit Emacs and
+invoke Emacs again.
 
 # #+caption[Prepare the user-emacs-directory]:
 # #+caption: Clone and initialize the user-emacs-directory.
@@ -99,18 +100,15 @@ presentations.
 
 The [[https://github.com/bdarcus/citar][Citar]] extension package provides quick filtering and selecting of
 bibliographic entries, and the option to run different commands on those
-selections.  [[https://github.com/bdarcus/citar][Citar]] requires at least [[info:org#Top][Org (info)]]-9.5 , which is already part of
-Emacs-28.1.  [[https://github.com/bdarcus/citar][Citar]] exploits the enhancements of Emacs' builtin selection
-mechanism provided by the extension packages [[https://github.com/minad/vertico][vertico]], [[https://github.com/oantolin/embark][embark]], [[https://github.com/minad/marginalia][marginalia]], and
-[[https://github.com/minad/consult][consult]].  The [[https://github.com/andras-simonyi/citeproc-el][citeproc]] extension package provides
-[[https://citationstyles.org/][CSL: citation style language]] processing
-capabilities to [[https://github.com/bdarcus/citar][citar]] and [[https://orgmode.org/][Org Mode]].  The [[https://github.com/citation-style-language/styles#readme][citation style language: style
-repository]] links to a curated repository of CSL styles.
+selections.  [[https://github.com/bdarcus/citar][Citar]] exploits the extension packages [[https://github.com/minad/vertico][Vertico]], [[https://github.com/oantolin/embark][Embark]], [[https://github.com/minad/marginalia][Marginalia]],
+and [[https://github.com/minad/consult][Consult]].  The [[https://github.com/andras-simonyi/citeproc-el][CiteProc]] extension package provides [[https://citationstyles.org/][CSL: citation style
+language]] processing capabilities to [[https://github.com/bdarcus/citar][Citar]] and [[https://orgmode.org/][Org Mode]].  A curated repository
+of CSL styles is the [[https://github.com/citation-style-language/styles#readme][citation style language repository]].
 
-The [[https://github.com/vedang/pdf-tools][pdf-tools]] extension package renders [[https://en.wikipedia.org/wiki/PDF][PDF]] file with the possibility to
+The [[https://github.com/vedang/pdf-tools][PDF-Tools]] extension package renders [[https://en.wikipedia.org/wiki/PDF][PDF]] file with the possibility to
 annotate the file or to click on anchors in the [[https://en.wikipedia.org/wiki/PDF][PDF]] file that link back to the
 original [[https://www.latex-project.org/][LaTeX]] file of the document.  An example of my work-flow are the steps
-to convert this [[info:org#Top][org]] file to [[https://en.wikipedia.org/wiki/PDF][PDF]] and to see the result with [[https://github.com/vedang/pdf-tools][pdf-tools]] in Emacs:
+to convert this [[info:org#Top][org]] file to [[https://en.wikipedia.org/wiki/PDF][PDF]] and to see the result with [[HTTPS://github.com/vedang/pdf-tools][PDF-Tools]] in Emacs:
 execute the commands ~pdf-tools-install~, ~org-babel-tangle~,
 ~org-latex-export-latex-to-latex~, and ~compile~.  This sets up an infinite
 [[https://www.latex-project.org/][LaTeX]] compilation loop to update and redisplay the [[https://en.wikipedia.org/wiki/PDF][PDF]] file after excution of
@@ -124,8 +122,9 @@ Here follows a list of interesting Emacs configurations:
    over my head.
 2. [[https://github.com/oantolin/emacs-config][Omar Antolin Camarena's configuration]] exploits built-in packages, Omar's own
    small packages, and large external packages.  Omar is the author of [[https://github.com/oantolin/orderless][orderless]]
-   and [[https://github.com/oantolin/embark][embark]].  I have stolen his idea of using ~custom-set-variables~ instead
-   of the customize interface although that is [[https://www.masteringemacs.org/article/bad-emacs-advice][bad Emacs advice]] for new users.
+   and [[https://github.com/oantolin/embark][embark]].  My use =setopt= to set Emacs options instead of the customize
+   interface comes from his idea of using =custom-set-variables= although that
+   is [[https://www.masteringemacs.org/article/bad-emacs-advice][bad Emacs advice]] for new users.
 3. [[https://gitlab.com/ambrevar/dotfiles][Pierre Neirhardt's configuration]] implements lazy loading without help of
    external packages.  I have stolen his approach of using lazy loading to
    silently ignore the setup stanzas of uninstalled extension packages.
@@ -196,165 +195,105 @@ that *Emacs is a self-documenting editor.*
 :CUSTOM_ID: sec:init-file-header
 :END:
 
-The =user-init-file= header requires =cl-lib=, backports new functions in
-Emacs-29.1 to Emacs-28.2, and customizes Emacs variables.  It consists of five
-parts in listing [[lst:backport-header]], [[lst:1st-custom-set-variables-call]],
-[[lst:2nd-custom-set-variables-call]], [[lst:3rd-custom-set-variables-call]], and
-[[lst:4th-custom-set-variables-call]] in order to limit the length of the listings
-for exporting to LaTeX.
+The =user-init-file= header requires =cl-lib= and sets Emacs options.  It
+consists of two parts in listing [[lst:1st-setopt-call]], and [[lst:2nd-setopt-call]] in
+order to limit the length of the listings for exporting to LaTeX.
 
 The [[info:elisp#Quoting][quoting (info)]] and the [[info:elisp#Backquote][backquote (info)]] pages explain how to understand the
-~'~ (quote), ~`~ (backquote), ~,~ (substitute) and ~@,~ (splice) in the
-~custom-set-variables~ function calls in listing
-[[lst:1st-custom-set-variables-call]], [[lst:2nd-custom-set-variables-call]],
-[[lst:3rd-custom-set-variables-call]], and [[lst:4th-custom-set-variables-call]].  A
-tutorial of how to use those reader macros is the [[https://mullikine.github.io/posts/macro-tutorial/][didactic emacs-lisp macro
-example]].
+~'~ (quote), ~`~ (backquote), ~,~ (substitute) and ~@,~ (splice) in in listing
+[[lst:1st-setopt-call]] and [[lst:2nd-setopt-call]].  A tutorial of how to use those
+reader macros is the [[https://mullikine.github.io/posts/macro-tutorial/][didactic emacs-lisp macro example]].
 
-The [[info:emacs#Init File][init file (info)]] does not load the ~custom-file~ as [[info:emacs#Saving Customizations][saving customizations
-(info)]] recommends because of the ~custom-set-variables~ function calls.
+The [[info:emacs#Init File][init file (info)]] does not load the ~custom-file~ in spite of the
+recommendation of [[info:emacs#Saving Customizations][saving customizations (info)]].
 
-#+caption[Header with backport of Emacs-29.1 functionality]:
-#+caption: Header with backport of Emacs-29.1 functionality.
-#+name: lst:backport-header
+#+caption[Set the first set of Emacs options]:
+#+caption: Set the first set of Emacs options.
+#+name: lst:1st-setopt-call
 #+begin_src emacs-lisp
 ;;; init.el --- user init file                    -*- lexical-binding: t -*-
 ;;; Commentary:
 ;;; Code:
 (require 'cl-lib)
 
-(when (version< emacs-version "29.0.0")
-  (defmacro setopt (&rest pairs)
-    "Set VARIABLE/VALUE pairs, and return the final VALUE.
-This is like `setq', but is meant for user options instead of
-plain variables.  This means that `setopt' will execute any
-`custom-set' form associated with VARIABLE.
+(when (version< emacs-version "29.0.60")
+  (error "This `init.el' requires at least Emacs-29.0.60"))
 
-\(fn [VARIABLE VALUE]...)"
-    (declare (debug setq))
-    (unless (zerop (mod (length pairs) 2))
-      (error "PAIRS must have an even number of variable/value members"))
-    (let ((expr nil))
-      (while pairs
-        (unless (symbolp (car pairs))
-          (error "Attempting to set a non-symbol: %s" (car pairs)))
-        (push `(setopt--set ',(car pairs) ,(cadr pairs))
-              expr)
-        (setq pairs (cddr pairs)))
-      (macroexp-progn (nreverse expr))))
-
-  (defun setopt--set (variable value)
-    (custom-load-symbol variable)
-    ;; Check that the type is correct.
-    (when-let ((type (get variable 'custom-type)))
-      (unless (widget-apply (widget-convert type) :match value)
-        (warn "Value `%S' does not match type %s" value type)))
-    (put variable 'custom-check-value (list value))
-    (funcall (or (get variable 'custom-set) #'set-default) variable value)))
-#+end_src
-
-#+caption[Customize the first set of Emacs variables]:
-#+caption: Customize the first set of Emacs variables.
-#+name: lst:1st-custom-set-variables-call
-#+begin_src emacs-lisp
-(custom-set-variables
- '(after-save-hook #'executable-make-buffer-file-executable-if-script-p)
- '(column-number-mode t)
- '(cursor-type 'box)
- `(custom-file ,(locate-user-emacs-file "custom.el"))
- '(epg-pinentry-mode 'loopback)
- '(global-hl-line-mode t)
- '(global-hl-line-sticky-flag t)
- '(history-delete-duplicates t)
- '(history-length 500)
- '(indent-tabs-mode nil)
- '(inhibit-startup-buffer-menu t)
- '(inhibit-startup-screen t)
- '(initial-buffer-choice t)
- '(initial-scratch-message "")
- `(insert-directory-program ,(or (executable-find "gls")
-                                 (executable-find "ls")))
- '(kill-ring-max 300))
-#+end_src
-
-#+caption[Customize the second set of Emacs variables]:
-#+caption: Customize the second set of Emacs variables.
-#+name: lst:2nd-custom-set-variables-call
-#+begin_src emacs-lisp
-(custom-set-variables
- ;; See https://github.com/melpa/melpa#mirrors for official Melpa mirrors.
- '(package-archives
-   '(("gnu" . "https://elpa.gnu.org/packages/")
-     ("gnu-devel" . "https://elpa.gnu.org/devel/")
-     ("melpa" . "https://melpa.org/packages/")
-     ;; ("melpa" . "https://www.mirrorservice.org/sites/melpa.org/packages/")
-     ("nongnu" . "https://elpa.nongnu.org/nongnu/")))
- ;; Pin packages to GNU ELPA for info or stability.
- '(package-pinned-packages
-   `,(delq nil `((auctex . "gnu")
-                 (compat . "gnu")
-                 (consult . "gnu-devel")
-                 ,(when (version< emacs-version "29.0.0")
-                    '(eglot . "gnu-devel"))
-                 (embark . "gnu-devel")
-                 (embark-consult . "gnu-devel")
-                 (engrave-faces . "gnu-devel")
-                 (hyperbole . "gnu-devel")
-                 (marginalia . "gnu-devel")
-                 (org . "gnu-devel")
-                 (queue . "gnu")
-                 (rainbow-mode . "gnu")
-                 (spinner . "gnu")
-                 (xr . "gnu")
-                 (vertico . "gnu-devel")))))
-#+end_src
-
-#+caption[Customize the third set of Emacs variables]:
-#+caption: Customize the third set of Emacs variables.
-#+name: lst:3rd-custom-set-variables-call
-#+begin_src emacs-lisp
-(custom-set-variables
- '(package-selected-packages
-   `,(delq nil `(async              ; asynchroneous processing
-                 debbugs            ; access the GNU bug tracker
-                 no-littering       ; keep `user-emacs-directory' clean
-                 org                ; thought organizer
-                 wgrep))))          ; open a writable grep buffer
-#+end_src
-
-#+caption[Customize the fourth set of Emacs variables]:
-#+caption: Customize the fourth set of Emacs variables.
-#+name: lst:4th-custom-set-variables-call
-#+begin_src emacs-lisp
-(custom-set-variables
- '(recentf-mode t)
- '(save-place-mode t)
- '(scroll-bar-mode nil)
- '(tab-always-indent 'complete)
- '(tab-width 8)
- '(tool-bar-mode nil)
- '(url-cookie-trusted-urls nil)
- '(url-cookie-untrusted-urls '(".*"))
- '(use-dialog-box nil)
- '(view-read-only t))
-
-(when (version< "28.0" emacs-version)
-  (custom-set-variables
-   '(mode-line-compact 'long)
-   '(next-error-message-highlight t)
-   '(use-short-answers t)))
+(setopt
+ after-save-hook #'executable-make-buffer-file-executable-if-script-p
+ column-number-mode t
+ cursor-type 'box
+ custom-file (locate-user-emacs-file "custom.el")
+ epg-pinentry-mode 'loopback
+ global-hl-line-mode t
+ global-hl-line-sticky-flag t
+ history-delete-duplicates t
+ history-length 500
+ indent-tabs-mode nil
+ inhibit-startup-buffer-menu t
+ inhibit-startup-screen t
+ initial-buffer-choice t
+ initial-scratch-message ""
+ insert-directory-program (or (executable-find "gls")
+                              (executable-find "ls"))
+ kill-ring-max 300
+ mode-line-compact 'long
+ next-error-message-highlight t
+ recentf-mode t
+ save-place-mode t
+ scroll-bar-mode nil
+ tab-always-indent 'complete
+ tab-width 8
+ tool-bar-mode nil
+ url-cookie-trusted-urls nil
+ url-cookie-untrusted-urls '(".*")
+ use-dialog-box nil
+ use-short-answers t
+ view-read-only t)
 
 (when (eq system-type 'darwin)
-  (custom-set-variables
-   '(ns-alternate-modifier nil)
-   '(ns-command-modifier 'meta)
-   '(ns-right-command-modifier 'super)))
+  (setopt ns-alternate-modifier nil
+          ns-command-modifier 'meta
+          ns-right-command-modifier 'super))
 
 (when (eq window-system 'ns)
   (add-to-list 'initial-frame-alist '(height . 51))
   (add-to-list 'initial-frame-alist '(width . 180)))
 #+end_src
 
+#+caption[Set the second set of Emacs options]:
+#+caption: Set the second set of Emacs options.
+#+name: lst:2nd-setopt-call
+#+begin_src emacs-lisp
+(setopt
+ ;; See https://github.com/melpa/melpa#mirrors for official Melpa mirrors.
+ ;; ("melpa" . "https://www.mirrorservice.org/sites/melpa.org/packages/")
+ package-archives '(("gnu" . "https://elpa.gnu.org/packages/")
+                    ("gnu-devel" . "https://elpa.gnu.org/devel/")
+                    ("melpa" . "https://melpa.org/packages/")
+                    ("nongnu" . "https://elpa.nongnu.org/nongnu/"))
+ ;; Pin packages to GNU ELPA for info or stability.
+ package-pinned-packages  '((auctex . "gnu")
+                            (compat . "gnu")
+                            (consult . "gnu-devel")
+                            (embark . "gnu-devel")
+                            (embark-consult . "gnu-devel")
+                            (engrave-faces . "gnu-devel")
+                            (hyperbole . "gnu-devel")
+                            (marginalia . "gnu-devel")
+                            (org . "gnu-devel")
+                            (queue . "gnu")
+                            (rainbow-mode . "gnu")
+                            (spinner . "gnu")
+                            (xr . "gnu")
+                            (vertico . "gnu-devel"))
+ package-selected-packages '(async         ; asynchroneous processing
+                             debbugs       ; access the GNU bug tracker
+                             no-littering  ; keep `user-emacs-directory' clean
+                             org           ; thought organizer
+                             wgrep))       ; open a writable grep buffer
+#+end_src
+
 * [[info:emacs#Package Installation][Install the selected packages (info)]]
 :PROPERTIES:
 :CUSTOM_ID: sec:install-selected-packages
@@ -425,9 +364,9 @@ the contents of packages and allows to update packages to the latest version.
 :CUSTOM_ID: sec:emacs-tree-sitter
 :END:
 
-#+caption[Customize Emacs Tree-sitter]:
-#+caption: Customize Emacs Tree-sitter.
-#+name: lst:customize-emacs-tree-sitter
+#+caption[Setup Emacs Tree-sitter]:
+#+caption: Setup Emacs Tree-sitter.
+#+name: lst:setup-emacs-tree-sitter
 #+begin_src emacs-lisp
 (when (require 'treesit nil 'noerror)
   ;; https://lists.gnu.org/archive/html/emacs-devel/2022-11/msg01372.html
@@ -446,9 +385,9 @@ the contents of packages and allows to update packages to the latest version.
 :CUSTOM_ID: sec:text-faces-or-styles
 :END:
 
-This setup does not configure [[info:emacs#Custom Themes][custom themes (info)]] in order to prevent endless
-useless tweaking.  See the [[https://protesilaos.com/codelog/2020-09-05-emacs-note-mixed-font-heights/][note on mixed font heights in Emacs]] for how to setup
-fonts properly.  It boils down to two rules:
+This setup does not use [[info:emacs#Custom Themes][custom themes (info)]] to avoid endless tweaking, but it
+does a minimal setup of fonts and faces.  See the [[https://protesilaos.com/codelog/2020-09-05-emacs-note-mixed-font-heights/][note on mixed font heights in
+Emacs]] for how to setup fonts properly.  It boils down to two rules:
 1. The height of the default face must be an integer number to make the height a
    physical quantity.
 2. The heights of all other faces must be real numbers to scale those heights
@@ -626,14 +565,16 @@ and [[lst:3rd-window-management]] implement a selection of his recommendations.
   (defun split-root-below (arg)
     "Split window below from the root or from the parent with ARG."
     (interactive "P")
-    (split-window (if arg (window-parent (selected-window))
+    (split-window (if arg
+                      (window-parent (selected-window))
                     (frame-root-window))
                   nil 'below nil))
 
   (defun split-root-right (arg)
     "Split window right from the root or from the parent with ARG."
     (interactive "P")
-    (split-window (if arg (window-parent (selected-window))
+    (split-window (if arg
+                      (window-parent (selected-window))
                     (frame-root-window))
                   nil 'right nil))
 
@@ -665,9 +606,9 @@ and [[lst:3rd-window-management]] implement a selection of his recommendations.
 #+begin_src emacs-lisp
 (with-eval-after-load 'emacs
   ;; https://www.masteringemacs.org/article/demystifying-emacs-window-manager
-  (custom-set-variables
-   '(switch-to-buffer-in-dedicated-window 'pop)
-   '(switch-to-buffer-obey-display-actions t))
+  (when (version< "29.0.0" emacs-version)
+    (setopt switch-to-buffer-in-dedicated-window 'pop
+            switch-to-buffer-obey-display-actions t))
 
   (add-to-list 'display-buffer-alist
                `(,(rx (or "*Apropos*"
@@ -787,37 +728,34 @@ of the facilities of [[info:emacs#Dired][dired (info)]] as follows:
 6. Switch to the =org-mode= buffer and use {{{kbd(C-c C-l)}}} to insert the
    =org-link= into the buffer.
 
-Listing [[lst:customize-dired]] makes the directory editor sort entries
+Listing [[lst:set-dired-options]] makes the directory editor sort entries
 alphabetically after grouping the directories before grouping the files by
 extension.
 
-#+caption[Customize =dired=]:
-#+caption: Customize =dired=.
-#+name: lst:customize-dired
+#+caption[Set =dired= options]:
+#+caption: Set =dired= options.
+#+name: lst:set-dired-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'dired
-  (custom-set-variables
-   '(dired-dwim-target t)
-   ;; | switch | action                                 |
-   ;; |--------+----------------------------------------|
-   ;; | -a     | also list hidden entries               |
-   ;; | -l     | use a long listing format              |
-   ;; | -X     | sort alphabetically by entry extension |
-   ;; | -G     | skip long listing format group names   |
-   ;; | -1     | list one entry per line                |
-   '(dired-listing-switches "-alGX1 --group-directories-first")
-   '(dired-recursive-copies 'always)
-   '(dired-recursive-deletes 'always)))
+  (setopt dired-dwim-target t
+          ;; | switch | action                                 |
+          ;; |--------+----------------------------------------|
+          ;; | -a     | also list hidden entries               |
+          ;; | -l     | use a long listing format              |
+          ;; | -X     | sort alphabetically by entry extension |
+          ;; | -G     | skip long listing format group names   |
+          ;; | -1     | list one entry per line                |
+          dired-listing-switches "-alGX1 --group-directories-first"
+          dired-recursive-copies 'always
+          dired-recursive-deletes 'always))
 
 (with-eval-after-load 'files
-  (custom-set-variables
-   ;; Ensure the use of `GNU-ls' from `coreutils' on darwin.
-   '(insert-directory-program (or (executable-find "gls")
-                                  (executable-find "ls")))))
+  ;; Ensure the use of `GNU-ls' from `coreutils' on darwin.
+  (setopt insert-directory-program (or (executable-find "gls")
+                                       (executable-find "ls"))))
 
 (with-eval-after-load 'wdired
-  (custom-set-variables
-   '(wdired-allow-to-change-permissions t)))
+  (setopt wdired-allow-to-change-permissions t))
 #+end_src
 
 Listing [[lst:extra-dired-key-bindings]] adds new key bindings to =dired-mode-map= to:
@@ -878,20 +816,19 @@ by experienced Emacs users.
 :CUSTOM_ID: sec:minibuffer-completion-styles
 :END:
 
-Listing [[lst:configure-minibuffer-completion-styles][configure minibuffer completion styles]] implements ideas of the post
-[[https://www.masteringemacs.org/article/understanding-minibuffer-completion][Understanding minibuffer completion]].
+Listing [[lst:set-minibuffer-options][set minibuffer options]] implements ideas of the post [[https://www.masteringemacs.org/article/understanding-minibuffer-completion][Understanding
+minibuffer completion]].
 
-#+caption[Configure =minibuffer= completion styles]:
-#+caption: Configure =minibuffer= completion styles.
-#+name: lst:configure-minibuffer-completion-styles
+#+caption[Set =minibuffer= options]:
+#+caption: Set =minibuffer= options.
+#+name: lst:set-minibuffer-options
 #+begin_src emacs-lisp
 (when (require  'minibuffer nil 'noerror)
   ;; https://www.masteringemacs.org/article/understanding-minibuffer-completion
-  (custom-set-variables
-   '(completion-category-overrides
-     '((file (styles basic substring))))
-   '(completion-ignore-case nil)
-   '(completion-styles '(basic flex partial-completion substring))))
+  (setopt
+   completion-category-overrides '((file (styles basic substring)))
+   completion-ignore-case nil
+   completion-styles '(basic flex partial-completion substring)))
 #+end_src
 
 * [[info:elisp#Processes][Processes (info)]]
@@ -939,6 +876,17 @@ or {{{kbd(C-h v)}}}.
 | info                         | help-map | {{{kbd(C-h i)}}} |
 |------------------------------+----------+------------------|
 
+#+begin_src emacs-lisp :tangle no
+(defun org-key-binding-macro (cmd)
+  (let* ((sym (intern-soft cmd))
+         (keys (and (commandp sym) (where-is-internal sym nil 'first-only)))
+         (prefix (seq-take keys (1- (length keys))))
+         (keymap (key-binding prefix 'accept-default)))
+    (format "%s %s %s {{{kbd(%s)}}}"
+            cmd keymap (help--binding-locus keys nil) (key-description keys))))
+
+(org-key-binding-macro 'consult-buffer)
+#+end_src
 
 ** [[info:emacs#Name Help][Shortdoc-display-group (info)]]
 :PROPERTIES:
@@ -1111,8 +1059,7 @@ Listing [[lst:configure-keycast]] configures =keycast=.
 ;; control buffer `ediff-setup-windows-plain' returns.
 (when (and (ensure-package-installation 'keycast)
            (require 'keycast nil 'noerror))
-  (custom-set-variables
-   '(keycast-mode-line-window-predicate 'keycast-bottom-right-window-p))
+  (setopt keycast-mode-line-window-predicate 'keycast-bottom-right-window-p)
 
   (defun keycast-log-update-buffer-plain ()
     (let ((buffer (get-buffer keycast-log-buffer-name)))
@@ -1171,11 +1118,11 @@ The code in listing [[lst:start-emacs-server]] starts the Emacs server.
 :END:
 
 The =latexmk= resource file in the next source code block shows how to use
-=emacsclient= to (re)display the PDF file in Emacs after each succesful
-(re)compilation on condition that the settings of the ~compile-command~ local
-variable in section are compatible.  The local variable ~compile-command~ in the
-[[#sec:local-variables][local variables]] section (only visible in =org= files, but not in =html= and
-=pdf= files) shows how to use the =latexmkrc= file.
+=emacsclient= to (re)display the PDF file in Emacs after each successful
+(re)compilation on condition that the local ~compile-command~ variable is
+correct.  The local ~compile-command~ variable in the [[#sec:local-variables][local variables]] section
+(only visible in =org= files, but not in =html= and =pdf= files) shows how to
+make use of the =latexmkrc= file.
 
 #+attr_latex: :options breaklines
 #+caption[Tangle the =Latexmk= resource file]:
@@ -1334,16 +1281,13 @@ file.
 #+caption: Enable =savehist-mode= and =vertico-mode=.
 #+name: lst:enable-vertico-mode
 #+begin_src emacs-lisp
-(when (fboundp 'savehist-mode)
+(when (require 'savehist nil 'noerror)
+  (setopt savehist-additional-variables '(eww-history
+                                          kill-ring
+                                          regexp-search-string
+                                          search-ring
+                                          search-string))
   (savehist-mode +1))
-(with-eval-after-load 'savehist-mode
-  (custom-set-variables
-   '(savehist-additional-variables
-     '(eww-history
-       kill-ring
-       regexp-search-string
-       search-ring
-       search-string))))
 (when (and (ensure-package-installation 'vertico)
            (fboundp 'vertico-mode))
   (vertico-mode +1))
@@ -1395,8 +1339,7 @@ file.
 #+begin_src emacs-lisp
 (when (ensure-package-installation 'marginalia)
   (with-eval-after-load 'orderless
-    (custom-set-variables
-     '(orderless-component-separator " +"))
+    (setopt orderless-component-separator " +")
 
     (defun just-one-face (fn &rest args)
       (let ((orderless-match-faces [completions-common-part]))
@@ -1410,7 +1353,7 @@ file.
 :CUSTOM_ID: sec:embark-configuration
 :END:
 
-Listing [[lst:configure-embark]] configures =embark= key bindings:
+Listing [[lst:bind-embark-commands][bind =embark= commands]] binds =embark= commands to the global key map:
 1. =embark-act= prompts the user for an action and performs it.
 2. Except for highlighting of email and web URLs, =embark-dwim= englobes the
    functionality of src_emacs-lisp{(find-library "goto-addr")} that activates
@@ -1425,9 +1368,9 @@ Listing [[lst:configure-embark]] configures =embark= key bindings:
    (for instance {{{kbd(C-x)}}} or {{{kbd(C-c)}}}) as typing {{{kbd(C-x C-h)}}}
    or {{{kbd(C-c C-h)}}} shows.
 
-#+caption[Configure =embark=]:
-#+caption: Configure =embark=.
-#+name: lst:configure-embark
+#+caption[Bind =embark= commands globally]:
+#+caption: Bind =embark= commands globally.
+#+name: lst:bind-embark-commands
 #+begin_src emacs-lisp
 (when (ensure-package-installation 'embark 'embark-consult)
   (when (fboundp 'embark-act)
@@ -1458,11 +1401,12 @@ Listing [[lst:enable-marginalia-mode]] enables =marginalia-mode=.
 
 ** [[info:consult#Top][Consult (info)]]
 :PROPERTIES:
-:CUSTOM_ID: sec:consult-configuration
+:CUSTOM_ID: sec:consult-setup
 :END:
 
-Consult provides practical commands based on the Emacs minibuffer completion
-function [[info:elisp#Minibuffer Completion][completing-read]].  Listing [[lst:configure-consult]] configures =consult=.
+[[info:consult#Top][Consult (info)]] provides practical commands based on the Emacs minibuffer
+completion function [[info:elisp#Minibuffer Completion][completing-read]].  Listing [[lst:bind-consult-commands][bind =consult= commands]] binds
+=consult= commands to different key maps.
 
 #+attr_latex: :booktabs yes :float table
 #+caption[Configuration specific key bindings]:
@@ -1511,13 +1455,11 @@ function [[info:elisp#Minibuffer Completion][completing-read]].  Listing [[lst:c
 |-----------------------------+----------------------+---------------------|
 
 
-#+caption[Configure =consult=]:
-#+caption: Configure =consult=.
-#+name: lst:configure-consult
+#+caption[Bind =consult= commands]:
+#+caption: Bind =consult= commands.
+#+name: lst:bind-consult-commands
 #+begin_src emacs-lisp
 (when (ensure-package-installation 'consult)
-  (custom-set-variables
-   '(consult-project-function #'(lambda (_) (vc-root-dir))))
   ;; C-c bindings (current-global-map)
   (global-set-key (kbd "C-c h") #'consult-history)
   (global-set-key (kbd "C-c m") #'consult-mode-command)
@@ -1551,19 +1493,18 @@ function [[info:elisp#Minibuffer Completion][completing-read]].  Listing [[lst:c
 
 ** [[https://company-mode.github.io/][Company: a modular complete anything framework for Emacs]]
 :PROPERTIES:
-:CUSTOM_ID: sec:company-configuration
+:CUSTOM_ID: sec:company-setup
 :END:
 
-Listing [[lst:configure-company]] configures =company=.
+Listing [[lst:setup-company]] configures =company=.
 
-#+caption[Configure =company=]:
-#+caption: Configure =company=.
-#+name: lst:configure-company
+#+caption[Setup =company=]:
+#+caption: Setup =company=.
+#+name: lst:setup-company
 #+begin_src emacs-lisp
 (when (fboundp 'company-mode)
-  (custom-set-variables
-   ;; https://github.com/purcell/emacs.d/issues/778
-   '(company-transformers '(company-sort-by-occurrence)))
+  ;; https://github.com/purcell/emacs.d/issues/778
+  (setopt company-transformers '(company-sort-by-occurrence))
   (dolist (hook '(LaTeX-mode-hook
                   org-mode-hook
                   emacs-lisp-mode-hook
@@ -1616,12 +1557,13 @@ of {{{kbd(M-x replace-regexp)}}} using =(regular-expression transform)= pairs.
 :END:
 
 [[https://github.com/Wilfred/deadgrep#readme][Deadgrep]] uses [[https://github.com/BurntSushi/ripgrep#readme][ripgrep]] for superfast text searching in the default directory or
-the current [[https://en.wikipedia.org/wiki/Version_control][VCS]] directory tree.  Listing [[lst:configure-deadgrep]] binds =deadgrep=
-to {{{kbd(M-s d)}}} and =deadgrep-edit-mode= to {{{kbd(C-c C-w)}}}.
+the current [[https://en.wikipedia.org/wiki/Version_control][VCS]] directory tree.  Listing [[lst:bind-deadgrep-commands][setup =deadgrep= commands]] binds
+=deadgrep= globally to {{{kbd(M-s d)}}} and =deadgrep-edit-mode= locally to
+{{{kbd(C-c C-w)}}}.
 
-#+caption[Configure =deadgrep=]:
-#+caption: Configure =deadgrep=.
-#+name: lst:configure-deadgrep
+#+caption[Bind =deadgrep= commands]:
+#+caption: Bind =deadgrep= commands.
+#+name: lst:bind-deadgrep-commands
 #+begin_src emacs-lisp
 (when (and (ensure-package-installation 'deadgrep)
            (fboundp 'deadgrep))
@@ -1637,37 +1579,34 @@ to {{{kbd(M-s d)}}} and =deadgrep-edit-mode= to {{{kbd(C-c C-w)}}}.
 
 [[https://www.genivia.com/get-ugrep.html][Ugrep]] is an ultra fast grep with interactive query UI and fuzzy search.  The
 pages [[https://github.com/Genivia/ugrep#emacs][Using ugrep within Emacs]] and [[https://manueluberti.eu/emacs/2022/08/07/emacs-ugrep/][Ugrep in Emacs]] show how to make Emacs use it
-with [[info:emacs#Grep Searching][lgrep]] and [[info:emacs#Xref][xref]].  Listing [[lst:use-ugrep]] shows my implementation of the
-suggestions on those pages.
+with [[info:emacs#Grep Searching][lgrep]] and [[info:emacs#Xref][xref]].  Listing [[lst:set-grep+xref-options][set =grep= and =xref= options]] shows my
+implementation of the suggestions on those pages.
 
-#+caption[Use =ugrep= when available]:
-#+caption: Use =ugrep= when available.
-#+name: lst:use-ugrep
+#+caption[Set =grep= and =xref= options to use =ugrep= when available]:
+#+caption: Set =grep= and =xref= options to use =ugrep= when available.
+#+name: lst:set-grep+xref-options
 #+begin_src emacs-lisp
 (when (executable-find "ugrep")
   (with-eval-after-load 'grep
-    (custom-set-variables
-     `(grep-template ,(string-join '("ugrep"
-                                     "--color=always"
-                                     "--decompress"
-                                     "--ignore-binary"
-                                     "--ignore-case"
-                                     "--include=\"<F>\""
-                                     "--line-number"
-                                     "--null"
-                                     "--recursive"
-                                     "--regexp=<R>")
-                                   " "))))
+    (setopt grep-template (string-join '("ugrep"
+                                         "--color=always"
+                                         "--decompress"
+                                         "--ignore-binary"
+                                         "--ignore-case"
+                                         "--include=\"<F>\""
+                                         "--line-number"
+                                         "--null"
+                                         "--recursive"
+                                         "--regexp=<R>")
+                                       " ")))
   (with-eval-after-load 'xref
-    (custom-set-variables
-     '(xref-search-program-alist
-       '((grep
-          . "xargs -0 grep <C> --null -snHE -e <R>")
-         (ripgrep
-          . "xargs -0 rg <C> --null -nH --no-heading --no-messages -g '!*/' -e <R>")
-         (ugrep
-          . "xargs -0 ugrep <C> --null -ns -e <R>")))
-     '(xref-search-program 'ugrep))))
+    (setopt
+     xref-search-program 'ugrep
+     xref-search-program-alist
+     `((grep . "xargs -0 grep <C> --null -snHE -e <R>")
+       (ripgrep . ,(concat "xargs -0 rg <C> --null -nH"
+                          " --no-heading --no-messages -g '!*/' -e <R>"))
+       (ugrep . "xargs -0 ugrep <C> --null -ns -e <R>")))))
 #+end_src
 
 ** [[https://github.com/mattiase/xr#readme][XR - Emacs regexp parser and analyzer]]
@@ -1699,23 +1638,23 @@ regexp strings.
 Video links to complete the [[info:ediff#Top][ediff (info)]] manual are:
 1. [[https://www.youtube.com/watch?v=6ZWp05OW1c0][Emergency Emacs]].
 2. [[https://protesilaos.com/codelog/2020-04-10-emacs-smerge-ediff/][Use =smerge= and =ediff= to resolve file conflicts]].
-Listing [[lst:configure-ediff]] configures =ediff= to display all its buffers in a
+Listing [[lst:setup-ediff]] configures =ediff= to display all its buffers in a
 single frame and to make all text visible prior to ediffing Org buffers.
 
-#+caption[Configure =ediff=]:
-#+caption: Configure =ediff=.
-#+name: lst:configure-ediff
+#+caption[Setup =ediff=]:
+#+caption: Setup =ediff=.
+#+name: lst:setup-ediff
 #+begin_src emacs-lisp
 (with-eval-after-load 'emacs
-  (custom-set-variables
-   '(ediff-merge-split-window-function #'split-window-horizontally)
-   '(ediff-split-window-function #'split-window-horizontally)
-   '(ediff-window-setup-function #'ediff-setup-windows-plain)))
+  (setopt ediff-merge-split-window-function #'split-window-horizontally
+          ediff-split-window-function #'split-window-horizontally
+          ediff-window-setup-function #'ediff-setup-windows-plain))
 (with-eval-after-load 'org
   ;; https://github.com/oantolin/emacs-config#readme
   (defun ediff-with-org-show-all ()
     "Expand all headings prior to ediffing org buffers."
-    (add-hook 'ediff-prepare-buffer-hook #'org-show-all nil t))
+    (add-hook 'ediff-prepare-buffer-hook #'org-fold-show-all nil t))
+
   (add-hook 'org-mode-hook #'ediff-with-org-show-all))
 #+end_src
 
@@ -1851,9 +1790,9 @@ In order to use [[https://github.com/vedang/pdf-tools][pdf-tools]], you have to
 installation of [[https://github.com/vedang/pdf-tools][pdf-tools]] from [[https://melpa.org/][MELPA]] or after each update of [[https://github.com/freedesktop/poppler][poppler]] to build or
 rebuild the =epdfinfo= executable that serves the [[https://en.wikipedia.org/wiki/PDF][PDF]] files to Emacs.
 
-#+caption[Configure =pdf-tools=]:
-#+caption: Configure =pdf-tools=.
-#+name: lst:configure-pdf-tools
+#+caption[Setup =pdf-tools=]:
+#+caption: Setup =pdf-tools=.
+#+name: lst:setup-pdf-tools
 #+begin_src emacs-lisp
 (when (and (ensure-package-installation 'pdf-tools 'saveplace-pdf-view)
            (fboundp 'pdf-loader-install))
@@ -1868,9 +1807,8 @@ rebuild the =epdfinfo= executable that serves the [[https://en.wikipedia.org/wik
     (define-key pdf-outline-minor-mode-map (kbd "O") #'pdf-outline))
 
   (with-eval-after-load 'pdf-view
-    (custom-set-variables
-     '(pdf-view-display-size 'fit-page)
-     `(pdf-view-use-scaling ,(eq system-type 'darwin)))
+    (setopt pdf-view-display-size 'fit-page
+            pdf-view-use-scaling (eq system-type 'darwin))
     (require 'saveplace-pdf-view nil 'noerror)))
 #+end_src
 
@@ -1890,35 +1828,35 @@ elisp library file has no autoload cookie.  Without prior loading of =tex.el=,
 Emacs will complain that ~TeX-master~ is no safe local variable in case it reads
 a LaTeX file that sets ~TeX-master~.  The list below summarizes the main [[https://en.wikipedia.org/wiki/AUCTeX][AUCTeX]]
 configuration objectives:
-1. Listing [[lst:require-tex]] ensures installation of [[https://en.wikipedia.org/wiki/AUCTeX][AUCTeX]] and initializes [[https://en.wikipedia.org/wiki/AUCTeX][AUCTeX]]
-   properly for =LuaTeX= or =LuaLaTeX=.
-2. Listing [[lst:require-tex]] also enables [[https://git.savannah.gnu.org/cgit/auctex.git/patch/?id=f464242eab092e610dda6b654e6fd197ef649d3eAA][indenting between square brackets]]
+1. Listing [[lst:set-tex-options]] ensures installation of [[https://en.wikipedia.org/wiki/AUCTeX][AUCTeX]] and initializes
+   [[https://en.wikipedia.org/wiki/AUCTeX][AUCTeX]] properly for =LuaTeX= or =LuaLaTeX=.
+2. Listing [[lst:set-tex-options]] also enables [[https://git.savannah.gnu.org/cgit/auctex.git/patch/?id=f464242eab092e610dda6b654e6fd197ef649d3eAA][indenting between square brackets]]
    which is a recent feature.
 3. Listing [[lst:update-lualatex-opentype-font-name-database]] defines a function to
    update the =OpenType Font= name database for =LuaLaTeX= when the output of
    =LuaLaTeX= shows missing fonts.
-4. Listing [[lst:configure-bibtex]] configures the Emacs =bibtex= library to use the
+4. Listing [[lst:set-bibtex-options]] configures the Emacs =bibtex= library to use the
    LaTeX =BiBTeX= dialect for backwards compatibility.
-5. Listing [[lst:configure-font-latex]] disables font scaling of section titles.
-6. Listing [[lst:configure-latex]] configures =latex= for a full featured
+5. Listing [[lst:set-font-latex-options]] disables font scaling of section titles.
+6. Listing [[lst:set-latex-options]] configures =latex= for a full featured
    =LaTeX-section-command=.
 
-#+caption[Require and configure =TeX=]:
-#+caption: Require and configure =TeX=.
-#+name: lst:require-tex
+#+caption[Ensure =AUCTeX= installation and set =TeX= option]:
+#+caption: Ensure =AUCTeX= installation and set =TeX= option.
+#+name: lst:set-tex-options
 #+begin_src emacs-lisp
 (when (ensure-package-installation 'auctex)
   ;; Use `require' to make `TeX-master' a safe local variable.
   (when (require 'tex nil 'noerror)
-    (custom-set-variables
-     '(TeX-auto-save t)
-     '(TeX-engine 'luatex)
-     '(TeX-indent-close-delimiters "]")
-     '(TeX-indent-open-delimiters "[")
-     '(TeX-install-font-lock #'font-latex-setup)
-     '(TeX-parse-self t)
+    (setopt
+     TeX-auto-save t
+     TeX-engine 'luatex
+     TeX-indent-close-delimiters "]"
+     TeX-indent-open-delimiters "["
+     TeX-install-font-lock #'font-latex-setup
+     TeX-parse-self t
      ;; Disable `TeX-electric-math' to prevent collisions with `smartparens'.
-     '(TeX-electric-math nil))))
+     TeX-electric-math nil)))
 #+end_src
 
 #+caption[Update the =LuaLaTeX OpenType Font=  name database]:
@@ -1937,35 +1875,33 @@ configuration objectives:
         (error "%s" (string-trim output))))))
 #+end_src
 
-#+caption[Configure =bibtex=]:
-#+caption: Configure =bibtex=.
-#+name: lst:configure-bibtex
+#+caption[Set =bibtex= options]:
+#+caption: Set =bibtex= options.
+#+name: lst:set-bibtex-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'bibtex
-  (custom-set-variables '(bibtex-dialect 'BibTeX)))
+  (setopt bibtex-dialect 'BibTeX))
 #+end_src
 
-#+caption[Configure =font-latex=]:
-#+caption: Configure =font-latex=.
-#+name: lst:configure-font-latex
+#+caption[Set =font-latex= options]:
+#+caption: Set =font-latex= options.
+#+name: lst:set-font-latex-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'font-latex
-  (custom-set-variables
-   '(font-latex-fontify-sectioning 1.0)))
+  (setopt font-latex-fontify-sectioning 1.0))
 #+end_src
 
-#+caption[Configure =latex=]:
-#+caption: Configure =latex=.
-#+name: lst:configure-latex
+#+caption[Set =latex= options]:
+#+caption: Set =latex= options.
+#+name: lst:set-latex-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'latex
-  (custom-set-variables
-   '(LaTeX-electric-left-right-brace t)
-   '(LaTeX-section-hook '(LaTeX-section-heading
-                          LaTeX-section-title
-                          LaTeX-section-toc
-                          LaTeX-section-section
-                          LaTeX-section-label))))
+  (setopt LaTeX-electric-left-right-brace t
+          LaTeX-section-hook '(LaTeX-section-heading
+                               LaTeX-section-title
+                               LaTeX-section-toc
+                               LaTeX-section-section
+                               LaTeX-section-label)))
 #+end_src
 
 *** [[https://gitlab.com/matsievskiysv/math-preview/-/blob/master/README.md][Math-preview]]
@@ -1976,9 +1912,9 @@ configuration objectives:
 [[https://gitlab.com/matsievskiysv/math-preview/-/blob/master/README.md][Math-preview]] uses [[https://docs.mathjax.org/en/latest/][Mathjax-3]] to display [[https://www.latex-project.org/][LaTeX]], [[https://www.w3.org/Math/][MathML]],and [[http://asciimath.org/][asciimath]] in Emacs
 buffers with help of an external [[https://nodejs.org][node.js]] program.
 
-#+caption[Configure =math-preview=]:
-#+caption: Configure =math-preview=.
-#+name: lst:configure-math-preview
+#+caption[Setup =math-preview=]:
+#+caption: Setup =math-preview=.
+#+name: lst:setup-math-preview
 #+begin_src emacs-lisp
 (when (ensure-package-installation 'math-preview)
   (with-eval-after-load 'math-preview
@@ -2031,7 +1967,7 @@ zeromatrix zmat")))
 
 *** TODO Improve the AUCTeX configuration slowly
 :PROPERTIES:
-:CUSTOM_ID: sec:configure-auctex-slowly
+:CUSTOM_ID: sec:setup-auctex-slowly
 :END:
 
 [[https://github.com/thisirs/dotemacs/blob/master/lisp/init-auctex.el][AUCTeX setup of an experienced user]]
@@ -2061,11 +1997,11 @@ of the [[info:org#Top][Org (info)]] manual.
 :CUSTOM_ID: sec:activate-org
 :END:
 
-#+caption[Activate =Org=]:
-#+caption: Activate =Org=.
-#+name: lst:activate-org
+#+caption[Bind =Org= commands globally]:
+#+caption: Bind =Org= commands globally.
+#+name: lst:bind-org-commands
 #+begin_src emacs-lisp
-(when (cl-every #'fboundp '(org-agenda org-capture))
+(with-eval-after-load 'emacs
   (global-set-key (kbd "C-c a") #'org-agenda)
   (global-set-key (kbd "C-c c") #'org-capture)
   (with-eval-after-load 'ol
@@ -2073,41 +2009,41 @@ of the [[info:org#Top][Org (info)]] manual.
     (global-set-key (kbd "C-c C-l") #'org-insert-link-global)))
 #+end_src
 
-*** Org customization
+*** Setup Org
 :PROPERTIES:
-:CUSTOM_ID: sec:customize-org
+:CUSTOM_ID: sec:setup-org
 :END:
 
-I have split the initial customization of [[https://orgmode.org/][Org-mode]] over several listings.  Here,
-follows a list detailing and motivating each listing:
-1. Listing [[lst:customize-org]] handles basic customization of [[https://orgmode.org/][Org-mode]] variables
-2. Listing [[lst:customize-org-babel]] handles basic customization of [[https://orgmode.org/][Org-mode]]
-   variables specific to [[info:org#Working with Source Code][working with source code (info)]] and it selects the
-   Python interpreter by means of
+I have split the initial [[https://orgmode.org/][Org-mode]] setup over several listings.  Here, follows a
+list detailing and motivating each listing:
+1. Listing [[lst:set-org-options]] handles basic [[https://orgmode.org/][Org-mode]] options.
+2. Listing [[lst:set-org-babel-options]] handles basic [[https://orgmode.org/][Org-mode]] options specific to
+   [[info:org#Working with Source Code][work with source code (info)]] and it
+   selects the Python interpreter by means of
    src_emacs-lisp{(choose-common-python-interpreter)} defined in listing
    [[lst:choose-common-python-interpreter]].
-3. Listing [[lst:customize-org-link]] handle basic customization of [[https://orgmode.org/][Org-mode]]
-   variables specific to [[info:org#Hyperlinks][hyperlinks (info)]].
-4. Listing [[lst:configure-org-mode-map]] extends the =org-mode-map= with useful
+3. Listing [[lst:set-org-link-options]] handles [[https://orgmode.org/][Org-mode]] options specific to
+   [[info:org#Hyperlinks][hyperlinks (info)]].
+4. Listing [[lst:setup-org-mode-map]] extends the =org-mode-map= with useful
    key-bindings.
-5. Listing [[lst:customize-org-src]] facilitates [[info:org#Editing Source Code][editing Python source code blocks]],
+5. Listing [[lst:setup-org-src]] facilitates [[info:org#Editing Source Code][editing Python source code blocks]],
    and it provides a function to remove the indentation of all =org-src-mode=
    blocks without =-i= switch.
-6. Listing [[lst:customize-ob-python]] allows to pretty-print Python session source
+6. Listing [[lst:setup-ob-python]] allows to pretty-print Python session source
    block values with [[https://github.com/psf/black#readme][black]] instead of [[https://docs.python.org/3/library/pprint.html][pprint]].
-7. Listing [[lst:customize-org-export-ui]] selects the =non-intrusive= expert user
+7. Listing [[lst:set-org-export-options]] selects the =non-intrusive= expert user
    interface for export dispatching.
-8. Listing [[lst:customize-org-for-lualatex-export]] and
-   [[lst:customize-ox-latex-for-lualatex-export]] configure [[https://orgmode.org/][Org-mode]] to generate
+8. Listing [[lst:setup-org-for-lualatex-export]] and
+   [[lst:set-ox-latex-options-for-lualatex-export]] configure [[https://orgmode.org/][Org-mode]] to generate
    output for the LuaLaTeX compiler.
-9. Listing [[lst:customize-org-latex-classes]] defines [[info:org#LaTeXspecificexportsettings][org-latex-classes (info)]] for
+9. Listing [[lst:setup-org-latex-classes]] defines [[info:org#LaTeXspecificexportsettings][org-latex-classes (info)]] for
    backward compatibility. See table [[tab:org-latex-class-tag-placeholder]] and
    type {{{kbd(C-hv org-latex-classes)}}} for an explanation of the code in
-   listing [[lst:customize-org-latex-classes]].
+   listing [[lst:setup-org-latex-classes]].
 
-#+caption[Customize =Org=]:
-#+caption: Customize =Org=.
-#+name: lst:customize-org
+#+caption[Set basic =Org= options]:
+#+caption: Set basic =Org= options.
+#+name: lst:set-org-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'org
   (custom-set-variables
@@ -2131,74 +2067,69 @@ follows a list detailing and motivating each listing:
                  ,(when (and (fboundp 'choose-common-python-interpreter)
                              (fboundp 'choose-common-python-linter))
                     '(python . t))
-                 (shell . t))))
-   '(org-export-backends '(ascii beamer html icalendar latex odt texinfo))
-   '(org-file-apps '((auto-mode . emacs)
-                     (directory . emacs)
-                     ("\\.mm\\'" . default)
-                     ("\\.x?html?\\'" . default)
-                     ("\\.pdf\\'" . emacs)))
-   '(org-modules '(ol-bibtex
-                   ol-doi
-                   ol-eww
-                   ol-info
-                   org-id
-                   org-protocol
-                   org-tempo))
-   '(org-structure-template-alist '(("a" . "export ascii")
-                                    ("c" . "center")
-                                    ("C" . "comment")
-                                    ("e" . "example")
-                                    ("E" . "export")
-                                    ("h" . "export html")
-                                    ("l" . "export latex")
-                                    ("q" . "quote")
-                                    ("s" . "src")
-                                    ("p" . "src python -i :session")
-                                    ("v" . "verse")))))
+                 (shell . t)))))
+  (setopt
+   org-export-backends '(ascii beamer html icalendar latex odt texinfo)
+   org-file-apps '((auto-mode . emacs)
+                   (directory . emacs)
+                   ("\\.mm\\'" . default)
+                   ("\\.x?html?\\'" . default)
+                   ("\\.pdf\\'" . emacs))
+   org-modules '(ol-bibtex
+                 ol-doi
+                 ol-eww
+                 ol-info
+                 org-id
+                 org-protocol
+                 org-tempo)
+   org-structure-template-alist '(("a" . "export ascii")
+                                  ("c" . "center")
+                                  ("C" . "comment")
+                                  ("e" . "example")
+                                  ("E" . "export")
+                                  ("h" . "export html")
+                                  ("l" . "export latex")
+                                  ("q" . "quote")
+                                  ("s" . "src")
+                                  ("p" . "src python -i :session")
+                                  ("v" . "verse"))))
 #+end_src
 
-#+caption[Customize =org-babel=]:
-#+caption: Customize =org-babel=.
-#+name: lst:customize-org-babel
+#+caption[Set =org-babel= options]:
+#+caption: Set =org-babel=.
+#+name: lst:set-org-babel-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'ob-core
-  (custom-set-variables
-   '(org-confirm-babel-evaluate nil)))
+  (setopt org-confirm-babel-evaluate nil))
 
 (with-eval-after-load 'ob-latex
-  (custom-set-variables
-   '(org-babel-latex-preamble
-     (lambda (_)
-       "\\documentclass[preview]{standalone}\n"))
-   '(org-babel-latex-begin-env
-     (lambda (_)
-       "\\begin{document}\n"))
-   '(org-babel-latex-end-env
-     (lambda (_)
-       "\\end{document}\n"))))
+  (setopt
+   org-babel-latex-preamble (lambda (_)
+                              "\\documentclass[preview]{standalone}\n")
+   org-babel-latex-begin-env (lambda (_)
+                               "\\begin{document}\n")
+   org-babel-latex-end-env (lambda (_)
+                             "\\end{document}\n")))
 
 (with-eval-after-load 'ob-lisp
   (with-eval-after-load 'sly
-    (custom-set-variables
-     '(org-babel-lisp-eval-fn #'sly-eval))))
+    (setopt org-babel-lisp-eval-fn #'sly-eval)))
 
 (with-eval-after-load 'ob-python
   (choose-common-python-interpreter 'python))
 #+end_src
 
-#+caption[Customize =org-link=]:
-#+caption: Customize =org-link=.
-#+name: lst:customize-org-link
+#+caption[Set =org-link= options]:
+#+caption: Set =org-link= options.
+#+name: lst:set-org-link-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'ol
-  (custom-set-variables
-   '(org-link-file-path-type 'relative)))
+  (setopt org-link-file-path-type 'relative))
 #+end_src
 
-#+caption[Configure =org-mode-map=]:
-#+caption: Configure =org-mode-map=.
-#+name: lst:configure-org-mode-map
+#+caption[Setup =org-mode-map=]:
+#+caption: Setup =org-mode-map=.
+#+name: lst:setup-org-mode-map
 #+begin_src emacs-lisp
 (with-eval-after-load 'emacs
   ;; From: "Nicolas Richard" <theonewiththeevillook@yahoo.fr>
@@ -2242,14 +2173,13 @@ When called twice, replace the previously inserted \\(\\) by one $."
     (define-key org-mode-map (kbd "M-q") #'org-fill-paragraph)))
 #+end_src
 
-#+caption[Customize =org-src=]:
-#+caption: Customize =org-src=.
-#+name: lst:customize-org-src
+#+caption[Setup =org-src=]:
+#+caption: Setup =org-src=.
+#+name: lst:setup-org-src
 #+begin_src emacs-lisp
 (with-eval-after-load 'emacs
   (with-eval-after-load 'org-src
-    (custom-set-variables
-     '(org-src-preserve-indentation t)))
+    (setopt org-src-preserve-indentation t))
 
   (declare-function org-babel-map-src-blocks "ext:ob-core" (file &rest body))
   (declare-function org-do-remove-indentation "ext:org-macs" (n skip-fl))
@@ -2272,9 +2202,9 @@ When called twice, replace the previously inserted \\(\\) by one $."
               (insert new))))))))
 #+end_src
 
-#+caption[Customize =ob-python=]:
-#+caption: Customize =ob-python=.
-#+name: lst:customize-ob-python
+#+caption[Setup =ob-python=]:
+#+caption: Setup =ob-python=.
+#+name: lst:setup-ob-python
 #+begin_src emacs-lisp
 (with-eval-after-load 'ob-python
   (defun org-babel-python-format-session-value-override
@@ -2311,18 +2241,17 @@ else:
               :override #'org-babel-python-format-session-value-override))
 #+end_src
 
-#+caption[Customize =org-export=]:
-#+caption: Customize =org-export=.
-#+name: lst:customize-org-export-ui
+#+caption[Set =org-export= options]:
+#+caption: Set =org-export= options.
+#+name: lst:set-org-export-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'ox
-  (custom-set-variables
-   '(org-export-dispatch-use-expert-ui t)))
+  (setopt org-export-dispatch-use-expert-ui t))
 #+end_src
 
-#+caption[Customize =org= for export to LuaLaTeX]:
-#+caption: Customize =org= for export to LuaLaTeX.
-#+name: lst:customize-org-for-lualatex-export
+#+caption[Setup =org= for export to LuaLaTeX]:
+#+caption: Setup =org= for export to LuaLaTeX.
+#+name: lst:setup-org-for-lualatex-export
 #+begin_src emacs-lisp
 (with-eval-after-load 'org
   ;; https://list.orgmode.org/87o84fd4oi.fsf@posteo.net/
@@ -2339,34 +2268,30 @@ else:
      :latex-header nil
      :latex-compiler ("lualatex -interaction nonstopmode -output-directory %o %f")
      :image-converter ("convert -density %D -trim -antialias %f -quality 100 %O")))
-  (custom-set-variables
-   '(org-preview-latex-default-process 'luamagick)
-   '(org-latex-default-packages-alist '(("" "fontspec" t ("lualatex"))
-                                        ("AUTO" "inputenc" t ("pdflatex"))
-                                        ("T1" "fontenc" t ("pdflatex"))
-                                        ("" "graphicx" t)
-                                        ("" "longtable" nil)
-                                        ("" "wrapfig" nil)
-                                        ("" "rotating" nil)
-                                        ("normalem" "ulem" t)
-                                        ("" "amsmath" t)
-                                        ("" "amssymb" t)
-                                        ("" "capt-of" nil)
-                                        ("" "hyperref" nil)))))
+  (setopt
+   org-preview-latex-default-process 'luamagick
+   org-latex-default-packages-alist '(("" "fontspec" t ("lualatex"))
+                                      ("AUTO" "inputenc" t ("pdflatex"))
+                                      ("T1" "fontenc" t ("pdflatex"))
+                                      ("" "graphicx" t)
+                                      ("" "longtable" nil)
+                                      ("" "wrapfig" nil)
+                                      ("" "rotating" nil)
+                                      ("normalem" "ulem" t)
+                                      ("" "amsmath" t)
+                                      ("" "amssymb" t)
+                                      ("" "capt-of" nil)
+                                      ("" "hyperref" nil))))
 #+end_src
 
-#+caption[Customize =ox-latex= for export to LuaLaTeX]:
-#+caption: Customize =ox-latex= for export to LuaLaTeX.
-#+name: lst:customize-ox-latex-for-lualatex-export
+#+caption[Set =ox-latex= options for export to LuaLaTeX]:
+#+caption: Set =ox-latex= options for export to LuaLaTeX.
+#+name: lst:set-ox-latex-options-for-lualatex-export
 #+begin_src emacs-lisp
 (with-eval-after-load 'ox-latex
-  (custom-set-variables
-   '(org-latex-pdf-process
-     ;; https://tecosaur.github.io/emacs-config/#compiling
-     `(,(concat "latexmk -f -pdf -%latex"
-                " -interaction=nonstopmode -shell-escape -outdir=%o %f")))
-   '(org-latex-compiler "lualatex")
-   '(org-latex-hyperref-template "\\hypersetup{
+  (setopt
+   org-latex-compiler "lualatex"
+   org-latex-hyperref-template "\\hypersetup{
   pdfauthor={%a},
   pdftitle={%t},
   pdfkeywords={%k},
@@ -2380,28 +2305,30 @@ else:
   linkcolor=blue,
   unicode=true,
   urlcolor=blue,
-}\n")
-   `,(if (version< emacs-version "29.0.0")
-         '(org-latex-listings 'minted)
-       '(org-latex-src-block-backend 'minted))
-   '(org-latex-minted-langs '((cc "c++")
-                              (conf "text")
-                              (cperl "perl")
-                              (diff "diff")
-                              (shell-script "bash")
-                              (json "json")
-                              (org "text")
-                              (toml "toml")))
-   '(org-latex-minted-options '(("bgcolor" "LightGoldenrodYellow")))
-   `(org-latex-logfiles-extensions
-     ',(cl-union '("lof" "lot") org-latex-logfiles-extensions :test #'equal))
-   '(org-latex-prefer-user-labels t)
-   '(org-latex-subtitle-separate t)))
+}\n"
+   org-latex-src-block-backend 'minted
+   org-latex-minted-langs '((cc "c++")
+                            (conf "text")
+                            (cperl "perl")
+                            (diff "diff")
+                            (shell-script "bash")
+                            (json "json")
+                            (org "text")
+                            (toml "toml"))
+   org-latex-minted-options '(("bgcolor" "LightGoldenrodYellow"))
+   org-latex-logfiles-extensions
+   (cl-union '("lof" "lot") org-latex-logfiles-extensions :test #'equal)
+   ;; https://tecosaur.github.io/emacs-config/#compiling
+   org-latex-pdf-process (list (concat "latexmk -f -pdf -%latex"
+                                       " -interaction=nonstopmode"
+                                       " -shell-escape -outdir=%o %f"))
+   org-latex-prefer-user-labels t
+   org-latex-subtitle-separate t))
 #+end_src
 
-#+caption[Customize =org-latex-classes= for backwards compatibility]:
-#+caption: Customize =org-latex-classes= for backwards compatibility.
-#+name: lst:customize-org-latex-classes
+#+caption[Setup =org-latex-classes= for backwards compatibility]:
+#+caption: Setup =org-latex-classes= for backwards compatibility.
+#+name: lst:setup-org-latex-classes
 #+begin_src emacs-lisp
 (with-eval-after-load 'ox-latex
   (mapc (function (lambda (element)
@@ -2450,8 +2377,8 @@ else:
 #+end_src
 
 #+attr_latex: :booktabs yes :float table
-#+caption[The relation tag-placeholder in listing [[lst:customize-org-latex-classes]]]:
-#+caption: The relation tag-placeholder in listing [[lst:customize-org-latex-classes]].
+#+caption[The relation tag-placeholder in listing [[lst:setup-org-latex-classes]]]:
+#+caption: The relation tag-placeholder in listing [[lst:setup-org-latex-classes]].
 #+name: tab:org-latex-class-tag-placeholder
 | tag | placeholder           |
 |-----+-----------------------|
@@ -2471,20 +2398,19 @@ else:
 well as CSL JSON bibliographic data with LaTeX, markdown, and org-cite editing
 support.  In combination with vertico, embark, marginalia, and consult, [[https://github.com/bdarcus/citar][Citar]]
 provides quick filtering and selecting of bibliographic entries from the
-minibuffer, as well as the option to run different commands on those
+minibuffer as well as the option to run different commands on those
 selections. The article [[https://kristofferbalintona.me/posts/202206141852/][Citations in org-mode: Org-cite and Citar]] tries to walk
 you from understanding the general context (bibliography producer, text
 processor, text to product convertor) to an Emacs setup.  Listing
-[[lst:configure-oc-cite+citar]] shows my =org-cite=, =citar=, and =org=
-configuration.
+[[lst:set-org-cite+citar-options]] shows my =org-cite=, =citar=, and =org= setup.
 
-#+caption[Configure =org-cite= with =citar=]:
-#+caption: Configure =oc-cite= with =citar=.
-#+name: lst:configure-oc-cite+citar
+#+caption[Set =org-cite= and =citar= options]:
+#+caption: Set =org-cite= and =citar= options.
+#+name: lst:set-org-cite+citar-options
 #+begin_src emacs-lisp
 (with-eval-after-load 'oc
   ;; Org-9.5 needs the requirements, but Org-9.6 does not.
-  (when (version< (org-version) "9.5.99")
+  (when (version< (org-version) "9.6")
     (require 'oc-biblatex)
     (require 'oc-csl)))
 
@@ -2497,22 +2423,19 @@ configuration.
       (citar-embark-mode +1)))
 
   (when (require 'citar nil 'noerror)
-    (custom-set-variables
-     '(citar-bibliography '("~/VCS/research/refs.bib"))
-     '(citar-library-file-extensions '("djvu" "pdf"))
-     '(citar-library-paths '("~/VCS/research/papers/"))))
+    (setopt citar-bibliography '("~/VCS/research/refs.bib")
+            citar-library-file-extensions '("djvu" "pdf")
+            citar-library-paths '("~/VCS/research/papers/")))
 
   (with-eval-after-load 'oc
-    (custom-set-variables
-     '(org-cite-export-processors '((latex biblatex)
-                                    (t csl)))
-     '(org-cite-global-bibliography '("~/VCS/research/refs.bib")))
+    (setopt org-cite-export-processors '((latex biblatex)
+                                         (t csl))
+            org-cite-global-bibliography '("~/VCS/research/refs.bib"))
 
     (when (require 'citar nil 'noerror)
-      (custom-set-variables
-       '(org-cite-activate-processor 'citar)
-       '(org-cite-follow-processor 'citar)
-       '(org-cite-insert-processor 'citar)))))
+      (setopt org-cite-activate-processor 'citar
+              org-cite-follow-processor 'citar
+              org-cite-insert-processor 'citar))))
 #+end_src
 
 Ref. [cite:@Schulte.MCSE.2011.41] shows that [[https://orgmode.org/][Org-mode]] is a simple, plain-text
@@ -2624,7 +2547,7 @@ this facility to a level acceptable for my workflow:
 (defun org-latex-engraved-source-block-filter (data _backend _info)
   "Replace \"Code\" with \"Breakable\" in non-floating environments.
 
-Customize `org-latex-engraved-preamble' to define a Breakable (non-floating)
+Set `org-latex-engraved-preamble' to define a Breakable (non-floating)
 environment and an unbreakable Code (floating) environment."
   (unless (string-match "^\\\\DeclareTColorBox\\[\\]{Breakable}"
                         org-latex-engraved-preamble)
@@ -3290,8 +3213,7 @@ prefixes all lines with \"#+latex_header: \"."
     '((:exports . "results") (:results . "raw")))
 
   (with-eval-after-load 'org-src
-    (custom-set-variables
-     '(org-src-window-setup 'current-window))
+    (setopt org-src-window-setup 'current-window)
 
     (add-to-list 'org-src-lang-modes '("toml" . conf-toml))
     (add-to-list 'org-src-lang-modes '("latex-header" . latex))
@@ -3896,15 +3818,14 @@ etymology, or thesaurus back-ends (currently limited to [[https://en.wikipedia.o
   ;; http://download.huzheng.org/dict.org/stardict-dictd_www.dict.org_gcide-2.4.2.tar.bz2
   (with-eval-after-load 'lexic
     (if-let ((lpp (executable-find "sdcv")))
-        (custom-set-variables
-         '(lexic-program-path lpp)
-         '(lexic-dictionary-alist '(("full" . t)))
+        (setopt
+         lexic-program-path lpp
+         lexic-dictionary-alist '(("full" . t))
          ;; sdcv --data-dir .local/share -l
-         '(lexic-dictionary-list
-           '("Webster's Revised Unabridged Dictionary (1913)"
-             "dictd_www.dict.org_gcide"))
-         '(lexic-dictionary-path "~/.local/share"))
-    (message "`lexic' fails to find the `sdcv' executable"))))
+         lexic-dictionary-list '("Webster's Revised Unabridged Dictionary (1913)"
+                                 "dictd_www.dict.org_gcide")
+         lexic-dictionary-path "~/.local/share")
+      (message "`lexic' fails to find the `sdcv' executable"))))
 #+end_src
 
 *** [[https://wordnet.princeton.edu/][Wordnet]]                                                        :noexport:
@@ -3923,8 +3844,7 @@ the [[https://github.com/gromnitsky/wordnut#readme][wordnut]] prerequisites.
 (when (ensure-package-installation 'wordnut)
   (with-eval-after-load 'wordnut
     (if-let ((wn (executable-find "wn")))
-        (custom-set-variables
-         '(wordnut-cmd wn))
+        (setopt wordnut-cmd wn)
       (message "`wordnut' fails to find the `wn' executable"))))
 #+end_src
 
@@ -3982,9 +3902,6 @@ mode independent [[https://github.com/joaotavora/eglot][Eglot]] configuration:
 #+name: lst:minimal-eglot-setup
 #+begin_src emacs-lisp
 (with-eval-after-load 'emacs
-  (when (version< emacs-version "29.0.0")
-    (ensure-package-installation 'eglot))
-
   ;; Replace `nil' with `t' for debugging.
   (when nil
     (when (require 'eglot nil t)
@@ -3992,19 +3909,19 @@ mode independent [[https://github.com/joaotavora/eglot][Eglot]] configuration:
             `(((python-ts-mod python-mode)
                . ,(eglot-alternatives
                    '(("pylsp" "-vv")
-                     ("ruff-lsp"))))))))
+                     ("ruff-lsp")))))))))
 
-  (with-eval-after-load 'eglot
-    (define-key eglot-mode-map (kbd "C-c n") 'flymake-goto-next-error)
-    (define-key eglot-mode-map (kbd "C-c p") 'flymake-goto-prev-error)
-    (define-key eglot-mode-map (kbd "C-c r") 'eglot-rename)))
+(with-eval-after-load 'eglot
+  (define-key eglot-mode-map (kbd "C-c n") 'flymake-goto-next-error)
+  (define-key eglot-mode-map (kbd "C-c p") 'flymake-goto-prev-error)
+  (define-key eglot-mode-map (kbd "C-c r") 'eglot-rename))
 #+end_src
 
 #+caption[Help to setup any =org-src-mode= buffers for =eglot=]:
 #+caption: Help to setup any =org-src-mode= buffers for =eglot=.
 #+name: lst:help-setup-org-src-mode-for-eglot
 #+begin_src emacs-lisp
-(when (fboundp 'eglot-ensure)
+(with-eval-after-load 'emacs
   (defcustom eglot-maybe-ensure-modes '(python-mode)
     "Modes where maybe `eglot-ensure' should be or has been called.
 This may be in the case of proper directory local variables or in
@@ -4049,7 +3966,7 @@ the Org-mode source block code before calling `eglot-ensure'."
 #+caption: Setup Python =org-src-mode= buffers for =eglot=.
 #+name: lst:setup-python-org-src-mode-for-eglot
 #+begin_src emacs-lisp
-(when (fboundp 'eglot-ensure)
+(with-eval-after-load 'emacs
   ;; https://www.reddit.com/r/emacs/comments/w4f4u3
   ;; /using_rustic_eglot_and_orgbabel_for_literate/
   (defun undo-eglot-org-babel-edit-prep()
@@ -4079,8 +3996,7 @@ This is to advice `org-edit-src-exit' and `org-edit-src-save'."
 #+caption: Experimental =narrow-format-all:python=.
 #+name: lst:narrow-format-all-python
 #+begin_src emacs-lisp
-(when (and (fboundp 'eglot-ensure)
-           (fboundp 'format-all-buffer))
+(when (fboundp 'format-all-buffer)
   (defun narrow-format-all:python ()
     "Format narrowed Python `org-src-mode' buffers correctly.
 Use this function instead of `format-all-buffer' on `org-babel-edit-prep:python'
@@ -4113,7 +4029,7 @@ prepared buffers."
 #+caption: Start =eglot= in case of a proper =dir-local-variables-alist=.
 #+name: lst:eglot-maybe-ensure
 #+begin_src emacs-lisp
-(when (fboundp 'eglot-ensure)
+(with-eval-after-load 'emacs
   (defun eglot-maybe-ensure ()
     (when (and (apply #'derived-mode-p eglot-maybe-ensure-modes)
                (assoc 'eglot-workspace-configuration dir-local-variables-alist))
@@ -4195,15 +4111,16 @@ Listing [[lst:sbcl-core-for-sly]] tangles to a script to dump such a [[http://ww
 #+begin_src emacs-lisp
 (when (ensure-package-installation 'sly)
   (with-eval-after-load 'sly
-    (custom-set-variables
-     ;; Customize `sly-default-lisp' instead of `inferior-lisp-program',
-     ;; because `sly' uses `inferior-lisp-program' only as a backwards
-     ;; compatibility fallback option.
-     '(sly-default-lisp 'sbcl)
-     `(sly-lisp-implementations
-       '((sbcl (,(executable-find "sbcl")
-                "--core"
-                ,(no-littering-expand-var-file-name "sbcl.core-for-sly"))))))
+    ;; Set `sly-default-lisp' instead of `inferior-lisp-program',
+    ;; because `sly' uses `inferior-lisp-program' only as a backwards
+    ;; compatibility fallback option.
+    ;; The warning "Value ‘sbcl’ does not match type function" is due to
+    ;; the buggy `defcustom' type of `sbcl-default-lisp' in `sly.el'.
+    (setopt sly-default-lisp 'sbcl
+            sly-lisp-implementations
+            `((sbcl (,(executable-find "sbcl")
+                     "--core"
+                     ,(no-littering-expand-var-file-name "sbcl.core-for-sly")))))
 
     (add-hook 'sly-mode-hook
               (defun on-sly-mode-hook ()
@@ -4323,7 +4240,7 @@ Here is a list of links describing how to program and debug [[info:elisp#Top][Em
 Ref. [cite:@Monnier.ACM-PL.4.1] exposes the evolution of Emacs Lisp and explains
 many Emacs Lisp idioms.
 
-Listing [[lst:setup-ielm][setup ielm]] customizes the [[https://wikemacs.org/wiki/IELM][Interactive Emacs Lisp Mode]] for better
+Listing [[lst:setup-ielm][setup ielm]] configures the [[https://wikemacs.org/wiki/IELM][Interactive Emacs Lisp Mode]] for better
 interoperability with [[https://smartparens.readthedocs.io/en/latest/][Smartparens]]: get help on the key bindings by means of
 src_emacs-lisp{(describe-function 'inferior-emacs-lisp-mode)}.
 
@@ -4511,32 +4428,28 @@ Finally, listing [[lst:flake8-nocolor][flake8-nocolor]] and [[lst:ruff-nocolor][
     (when (boundp 'org-babel-python-command)
       (pcase choice
         ("python"
-         (custom-set-variables
-          `(org-babel-python-command
-            ,(concat (or (executable-find "python3")
-                         (executable-find "python"))
-                     " -E"))))
+         (setopt org-babel-python-command
+                 (concat (or (executable-find "python3")
+                             (executable-find "python"))
+                         " -E")))
         ("ipython"
-         (custom-set-variables
-          `(org-babel-python-command
-            ,(concat (or (executable-find "ipython3")
-                         (executable-find "ipython"))
-                     " --simple-prompt --HistoryAccessor.enabled=False")))))
+         (setopt org-babel-python-command
+                 (concat (or (executable-find "ipython3")
+                              (executable-find "ipython"))
+                         " --simple-prompt --HistoryAccessor.enabled=False"))))
       (message "Now `org-babel-python-command' equals %S"
                org-babel-python-command))
     (when (boundp 'python-shell-interpreter)
       (pcase choice
         ("python"
-         (custom-set-variables
-          `(python-shell-interpreter
-            ,(or (executable-find "python3") (executable-find "python")))
-          '(python-shell-interpreter-args "-E -i")))
+         (setopt python-shell-interpreter (or (executable-find "python3")
+                                              (executable-find "python"))
+                 python-shell-interpreter-args "-E -i"))
         ("ipython"
-         (custom-set-variables
-          `(python-shell-interpreter
-            ,(or (executable-find "ipython3") (executable-find "ipython"))))
-         (setq python-shell-interpreter-args
-               "--simple-prompt --HistoryAccessor.enabled=False")))
+         (setopt python-shell-interpreter (or (executable-find "ipython3")
+                                              (executable-find "ipython"))
+                 python-shell-interpreter-args
+                 "--simple-prompt --HistoryAccessor.enabled=False")))
       (message "Now `python-shell-interpreter' equals %S"
                python-shell-interpreter))))
 #+end_src
@@ -4558,18 +4471,15 @@ Finally, listing [[lst:flake8-nocolor][flake8-nocolor]] and [[lst:ruff-nocolor][
     (when (and (boundp 'python-check-command) (boundp 'python-flymake-command))
       (pcase choice
         ("flake8-nocolor"
-         (custom-set-variables
-          `(python-check-command ,(executable-find choice))
-          `(python-flymake-command (list ,(executable-find choice) "-"))))
+         (setopt python-check-command (executable-find choice)
+                 python-flymake-command (list (executable-find choice) "-")))
         ("pyflakes"
-         (custom-set-variables
-          `(python-check-command ,(executable-find choice))
-          `(python-flymake-command `(,(executable-find choice)))))
+         (setopt python-check-command (executable-find choice)
+                 python-flymake-command `(,(executable-find choice))))
         ("ruff-nocolor"
-         (custom-set-variables
-          `(python-check-command ,(executable-find choice))
-          `(python-flymake-command
-            (list ,(executable-find choice) "--stdin-filename" "stdin" "-")))))
+         (setopt python-check-command (executable-find choice)
+                 python-flymake-command (list (executable-find choice)
+                                              "--stdin-filename" "stdin" "-"))))
       (when (bound-and-true-p python-check-custom-command)
         (setq python-check-custom-command nil))
       (message "Python checker commands are %S and %S"
@@ -4581,9 +4491,9 @@ Finally, listing [[lst:flake8-nocolor][flake8-nocolor]] and [[lst:ruff-nocolor][
 #+name: lst:setup-python-mode
 #+begin_src emacs-lisp
 (with-eval-after-load 'python
-  (custom-set-variables
-   '(python-indent-guess-indent-offset nil)
-   '(python-shell-completion-native-disabled-interpreters '("ipython3" "pypy")))
+  (setopt python-indent-guess-indent-offset nil
+          python-shell-completion-native-disabled-interpreters '("ipython3"
+                                                                 "pypy"))
   (choose-common-python-interpreter 'python)
   (choose-common-python-linter 'ruff-nocolor))
 #+end_src
@@ -5026,8 +4936,7 @@ setup and requires no configuration.
 #+begin_src emacs-lisp
 (when (and (ensure-package-installation 'ws-butler)
            (require 'ws-butler nil 'noerror))
-  (custom-set-variables
-   '(ws-butler-keep-whitespace-before-point nil))
+  (setopt ws-butler-keep-whitespace-before-point nil)
   (add-hook 'prog-mode-hook #'ws-butler-mode)
   (add-hook 'text-mode-hook #'ws-butler-mode))
 #+end_src
@@ -5080,10 +4989,9 @@ contrary to for instance [[https://github.com/Fanael/rainbow-delimiters#readme][
            ;; Require `smartparens-config' instead of `smartparens' to
            ;; disable pairing of the quote character for lisp modes.
            (require 'smartparens-config nil 'noerror))
-  (custom-set-variables
-   '(sp-base-key-bindings 'sp)
-   '(sp-override-key-bindings '(("C-(" . sp-backward-barf-sexp)
-                                ("C-)" . sp-forward-slurp-sexp))))
+  (setopt sp-base-key-bindings 'sp
+          sp-override-key-bindings '(("C-(" . sp-backward-barf-sexp)
+                                     ("C-)" . sp-forward-slurp-sexp)))
 
   (dolist (hook '(conf-toml-mode-hook prog-mode-hook text-mode-hook))
     (add-hook hook #'smartparens-mode))
@@ -5139,9 +5047,8 @@ code formatter for Python]].
 #+name: lst:enable-yas-global-mode
 #+begin_src emacs-lisp
 (when (ensure-package-installation 'yasnippet)
-  (custom-set-variables
-   ;; Set `yas-alias-to-yas/prefix-p' before loading `yasnippet'.
-   '(yas-alias-to-yas/prefix-p nil))
+  ;; Set `yas-alias-to-yas/prefix-p' before loading `yasnippet'.
+  (setopt yas-alias-to-yas/prefix-p nil)
   (when (require 'yasnippet nil 'noerror)
     (yas-global-mode +1)))
 #+end_src
@@ -5168,8 +5075,7 @@ and later.  Listing [[lst:setup-python-tempo]] configures =tempo= for =python-mo
 #+name: lst:configure-tempo-ui
 #+begin_src emacs-lisp
 (with-eval-after-load 'tempo
-  (custom-set-variables
-   '(tempo-interactive t))
+  (setopt tempo-interactive t)
 
   (defun setup-local-tempo-key-bindings ()
     "Initialize local `tempo' key bindings."
@@ -5290,7 +5196,7 @@ on any Org table, Org source block, Org block, or Org subtree.
 #+name: lst:configure-narrow-or-widen-dwim
 #+begin_src emacs-lisp
 (with-eval-after-load 'emacs
-  (autoload 'org-at-table-p "org-table")
+  (declare-function org-at-table-p "org" (&optional table-type))
 
   (defun org-narrow-to-table ()
     "Narrow buffer to table at point."
@@ -5346,16 +5252,14 @@ and names in buffers for debugging.
 #+begin_src emacs-lisp
 (when (and (ensure-package-installation 'rainbow-mode)
            (fboundp 'rainbow-mode))
-  (custom-set-variables
-   '(rainbow-x-colors-major-mode-list
-     '(c++-mode
-       c-mode
-       emacs-lisp-mode
-       inferior-emacs-lisp-mode
-       java-mode
-       lisp-interaction-mode
-       org-mode
-       python-mode)))
+  (setopt rainbow-x-colors-major-mode-list '(c++-mode
+                                             c-mode
+                                             emacs-lisp-mode
+                                             inferior-emacs-lisp-mode
+                                             java-mode
+                                             lisp-interaction-mode
+                                             org-mode
+                                             python-mode))
   (rainbow-mode +1))
 #+end_src
 
@@ -5424,12 +5328,11 @@ Listing [[lst:configure-browse-url]] configures =browse-url=.
             (seq (+? nonl) (or ".mp4" ".webm") eos)))
     "Match hyperlinks to open with mpv.")
 
-  (custom-set-variables
-   `(browse-url-generic-program ,(or (when (eq system-type 'darwin) "open")
-                                     (executable-find "firefox")))
-   '(browse-url-handlers
-     `((,browse-url-mpv-regexp . browse-url-mpv)
-       ("." . eww-browse-url)))))
+  (setopt
+   browse-url-generic-program (or (when (eq system-type 'darwin) "open")
+                                  (executable-find "firefox"))
+   browse-url-handlers `((,browse-url-mpv-regexp . browse-url-mpv)
+                         ("." . eww-browse-url))))
 #+end_src
 
 *** [[https://en.wikipedia.org/wiki/Eww_(web_browser)][Emacs Web Wowser]]
@@ -5572,50 +5475,50 @@ application/pdf; emacsclient %s
 :CUSTOM_ID: sec:webjump
 :END:
 
-Listing [[lst:configure-webjump]] binds {{{kbd(C-c j)}}} to =webjump= and
-initializes a list of =webjump-sites=.
+Listing [[lst:set-webjump-options]] binds {{{kbd(C-c j)}}} to =webjump= and
+sets the =webjump-sites= option.
 
 #+attr_latex: :options breaklines
-#+caption[Configure =webjump=]:
-#+caption: Configure =webjump=.
-#+name: lst:configure-webjump
+#+caption[Set =webjump= options and bind the =webjump= command]:
+#+caption: Set =webjump= options and bind the =webjump= command.
+#+name: lst:set-webjump-options
 #+begin_src emacs-lisp
 (when (fboundp 'webjump)
   (global-set-key (kbd "C-c j") 'webjump)
   (with-eval-after-load 'webjump
-    (custom-set-variables
-     '(webjump-sites
-       '(("CS 325 AI Programming" . "courses.cs.northwestern.edu/325")
-         ("Emacs News" . "sachachua.com/blog/category/emacs-news")
-         ("Mastering Emacs" . "www.masteringemacs.org")
-         ("Planet Emacs Life" . "planet.emacslife.com")
-         ("Real Python" . "realpython.com")
-         ("Worg - Org Mode Community" . "orgmode.org/worg")
-         ("Git: Emacs" . "git.savannah.gnu.org/cgit/emacs.git")
-         ("Git: Emacs Core Python Mode" .
-          "git.savannah.gnu.org/cgit/emacs.git/log/lisp/progmodes/python.el")
-         ("Git: GNU ELPA" . "git.savannah.gnu.org/cgit/emacs/elpa.git")
-         ("Git: NonGNU ELPA" . "git.savannah.gnu.org/cgit/emacs/nongnu.git")
-         ("Git: Org Mode" . "git.savannah.gnu.org/cgit/emacs/org-mode.git")
-         ("List: Org Mode" . "list.orgmode.org")
-         ("List: Emacs Developer Archives" .
-          "lists.gnu.org/archive/html/emacs-devel/")
-         ("List: Help GNU Emacs Archives" .
-          "lists.gnu.org/archive/html/help-gnu-emacs/")
-         ("Asian Pacific Journal Japan Focus" . "apjjf.org")
-         ("Counterpunch" . "www.counterpunch.org")
-         ("Dictionary FR" . [simple-query "www.cnrtl.fr"
-                                          "www.cnrtl.fr/definition/" ""])
-         ("Dictionary NL" . [simple-query "www.woorden.org"
-                                          "www.woorden.org/woord/" ""])
-         ("Le Figaro" . "www.lefigaro.fr")
-         ("Le Monde" . "www.lemonde.fr")
-         ("Libération" . "www.liberation.fr")
-         ("Monde Diplomatique" . "www.monde-diplomatique.fr")
-         ("NRC". "www.nrc.nl")
-         ("The Guardian" . "www.theguardian.com/international")
-         ("Trouw" . "www.trouw.nl")
-         ("Volkskrant" . "www.volkskrant.nl"))))))
+    (setopt
+     webjump-sites
+     '(("CS 325 AI Programming" . "courses.cs.northwestern.edu/325")
+       ("Emacs News" . "sachachua.com/blog/category/emacs-news")
+       ("Mastering Emacs" . "www.masteringemacs.org")
+       ("Planet Emacs Life" . "planet.emacslife.com")
+       ("Real Python" . "realpython.com")
+       ("Worg - Org Mode Community" . "orgmode.org/worg")
+       ("Git: Emacs" . "git.savannah.gnu.org/cgit/emacs.git")
+       ("Git: Emacs Core Python Mode" .
+        "git.savannah.gnu.org/cgit/emacs.git/log/lisp/progmodes/python.el")
+       ("Git: GNU ELPA" . "git.savannah.gnu.org/cgit/emacs/elpa.git")
+       ("Git: NonGNU ELPA" . "git.savannah.gnu.org/cgit/emacs/nongnu.git")
+       ("Git: Org Mode" . "git.savannah.gnu.org/cgit/emacs/org-mode.git")
+       ("List: Org Mode" . "list.orgmode.org")
+       ("List: Emacs Developer Archives" .
+        "lists.gnu.org/archive/html/emacs-devel/")
+       ("List: Help GNU Emacs Archives" .
+        "lists.gnu.org/archive/html/help-gnu-emacs/")
+       ("Asian Pacific Journal Japan Focus" . "apjjf.org")
+       ("Counterpunch" . "www.counterpunch.org")
+       ("Dictionary FR" . [simple-query "www.cnrtl.fr"
+                                        "www.cnrtl.fr/definition/" ""])
+       ("Dictionary NL" . [simple-query "www.woorden.org"
+                                        "www.woorden.org/woord/" ""])
+       ("Le Figaro" . "www.lefigaro.fr")
+       ("Le Monde" . "www.lemonde.fr")
+       ("Libération" . "www.liberation.fr")
+       ("Monde Diplomatique" . "www.monde-diplomatique.fr")
+       ("NRC". "www.nrc.nl")
+       ("The Guardian" . "www.theguardian.com/international")
+       ("Trouw" . "www.trouw.nl")
+       ("Volkskrant" . "www.volkskrant.nl")))))
 #+end_src
 
 ** [[info:gnus#Top][Reading News and Mail (info)]]
@@ -5652,22 +5555,19 @@ initializes a list of =webjump-sites=.
 #+name: lst:configure-gnus
 #+begin_src emacs-lisp
 (with-eval-after-load 'gnus
-  (custom-set-variables
-   '(gnus-select-method '(nntp "news.gmane.io"))))
+  (setopt gnus-select-method '(nntp "news.gmane.io")))
 
 (with-eval-after-load 'gnus-start
-  (custom-set-variables
-   '(gnus-check-bogus-newsgroups nil)
-   '(gnus-check-new-newsgroups 'ask-server)
-   '(gnus-read-newsrc-file t)
-   '(gnus-read-active-file 'some)
-   '(gnus-save-killed-list t)
-   '(gnus-save-newsrc-file t)
-   '(gnus-use-dribble-file t)))
+  (setopt gnus-check-bogus-newsgroups nil
+          gnus-check-new-newsgroups 'ask-server
+          gnus-read-newsrc-file t
+          gnus-read-active-file 'some
+          gnus-save-killed-list t
+          gnus-save-newsrc-file t
+          gnus-use-dribble-file t))
 
 (with-eval-after-load 'gnus-sum
-  (custom-set-variables
-   '(gnus-thread-hide-subtree t)))
+  (setopt gnus-thread-hide-subtree t))
 #+end_src
 
 ** [[info:emacs#Sending Mail][Sending Mail (info)]]
@@ -5687,12 +5587,10 @@ initializes a list of =webjump-sites=.
 #+caption: Configure =message=.
 #+name: lst:configure-message
 #+begin_src emacs-lisp
-(custom-set-variables
- '(user-full-name "Gerard Vermeulen")
- '(user-mail-address "gerard.vermeulen@posteo.net"))
+(setopt user-full-name "Gerard Vermeulen"
+        user-mail-address "gerard.vermeulen@posteo.net")
 (with-eval-after-load 'message
-  (custom-set-variables
-   '(message-sendmail-envelope-from 'header)))
+  (setopt message-sendmail-envelope-from 'header))
 #+end_src
 
 #+caption[Configure =sendmail=]:
@@ -5700,11 +5598,10 @@ initializes a list of =webjump-sites=.
 #+name: lst:configure-sendmail
 #+begin_src emacs-lisp
 (with-eval-after-load 'sendmail
-  (custom-set-variables
-   '(mail-specify-envelope-from t)
-   '(mail-envelope-from 'header)
-   '(send-mail-function #'sendmail-send-it)
-   `(sendmail-program ,(executable-find "msmtp"))))
+  (setopt mail-specify-envelope-from t
+          mail-envelope-from 'header
+          send-mail-function #'sendmail-send-it
+          sendmail-program (executable-find "msmtp")))
 #+end_src
 
 #+attr_latex: :options breaklines
@@ -5778,41 +5675,40 @@ user gerard.vermeulen@neel.cnrs.fr
 :CUSTOM_ID: sec:emacs-web-feed-reader
 :END:
 
-Listing [[lst:configure-elfeed]] configures =elfeed= and makes a minimal attempt to
-enable =emms=.
+Listing [[lst:set-elfeed-options]] sets =elfeed= options, binds the =elfeed=
+command, and makes a minimal attempt to enable =emms=.
 
 #+attr_latex: :options breaklines
-#+caption[Configure =elfeed=]:
-#+caption: Configure =elfeed=.
-#+name: lst:configure-elfeed
+#+caption[Set =elfeed= options and bind =elfeed= command]:
+#+caption: Set =elfeed= options and bind =elfeed= command.
+#+name: lst:set-elfeed-options
 #+begin_src emacs-lisp
 (when (and (ensure-package-installation 'elfeed)
            (fboundp 'elfeed))
   (global-set-key (kbd "C-x w") #'elfeed)
 
   (with-eval-after-load 'elfeed
-    (custom-set-variables
-     '(elfeed-feeds
-       '(("http://www.howardism.org/index.xml" h-abrams)
-         ("https://bitspook.in/archive/feed.xml" c-singh)
-         ("https://emacshorrors.com/feed.atom" v-schneidermann)
-         ("https://emacsninja.com/emacs.atom" v-schneidermann)
-         ("https://feeds.feedburner.com/InterceptedWithJeremyScahill"
-          j-scahill)
-         ("https://frame.work/fr/fr/blog.rss" framework)
-         ("https://nullprogram.com/feed/" c-wellons)
-         ("https://oremacs.com/atom.xml" o-krehel)
-         ("https://planet.emacslife.com/atom.xml" planet-emacs)
-         ("https://protesilaos.com/codelog.xml" p-stavrou)
-         ("https://sachachua.com/blog/category/emacs/feed" s-chua)
-         ("https://sciencescitoyennes.org/feed/" sciences)
-         ("https://tdodge.consulting/blog/rss.xml" t-dodge)
-         ("https://talkpython.fm/episodes/rss" talk-python)
-         ("https://updates.orgmode.org/feed/updates" org-updates)
-         ("https://www.bof.nl/rss/" bof)
-         ("https://www.democracynow.org/podcast-video.xml" dn)
-         ("https://www.laquadrature.net/fr/rss.xml" lqdn)
-         ("https://www.lemonde.fr/blog/huet/feed/" sciences)))))
+    (setopt
+     elfeed-feeds
+     '(("http://www.howardism.org/index.xml" h-abrams)
+       ("https://bitspook.in/archive/feed.xml" c-singh)
+       ("https://emacshorrors.com/feed.atom" v-schneidermann)
+       ("https://emacsninja.com/emacs.atom" v-schneidermann)
+       ("https://feeds.feedburner.com/InterceptedWithJeremyScahill" j-scahill)
+       ("https://frame.work/fr/fr/blog.rss" framework)
+       ("https://nullprogram.com/feed/" c-wellons)
+       ("https://oremacs.com/atom.xml" o-krehel)
+       ("https://planet.emacslife.com/atom.xml" planet-emacs)
+       ("https://protesilaos.com/codelog.xml" p-stavrou)
+       ("https://sachachua.com/blog/category/emacs/feed" s-chua)
+       ("https://sciencescitoyennes.org/feed/" sciences)
+       ("https://tdodge.consulting/blog/rss.xml" t-dodge)
+       ("https://talkpython.fm/episodes/rss" talk-python)
+       ("https://updates.orgmode.org/feed/updates" org-updates)
+       ("https://www.bof.nl/rss/" bof)
+       ("https://www.democracynow.org/podcast-video.xml" dn)
+       ("https://www.laquadrature.net/fr/rss.xml" lqdn)
+       ("https://www.lemonde.fr/blog/huet/feed/" sciences))))
 
   (with-eval-after-load 'elfeed-show
     (when (fboundp 'emms-all)
@@ -5825,46 +5721,39 @@ enable =emms=.
 :END:
 
 The link [[https://sqrtminusone.xyz/posts/2021-09-07-emms/][my emms and elfeed setup]] is a nice introduction to configuring and
-using =emms= with =elfeed=.  Listing [[lst:configure-emms]] configures =emms=.
+using =emms= with =elfeed=.  Listing [[lst:set-emms-options]] configures =emms=.
 
-#+caption[Configure =emms=]:
-#+caption: Configure =emms=.
-#+name: lst:configure-emms
+#+caption[Set =emms= options]:
+#+caption: Set =emms= options.
+#+name: lst:set-emms-options
 #+begin_src emacs-lisp
 (when (ensure-package-installation 'emms)
   (with-eval-after-load 'emms
-    (custom-set-variables
-     '(emms-player-list '(emms-player-mpd emms-player-mpv)))
+    (setopt emms-player-list '(emms-player-mpd emms-player-mpv))
     (emms-all))
 
   (with-eval-after-load 'emms-mode-line
-    (custom-set-variables
-     '(emms-mode-line-format "")))
+    (setopt emms-mode-line-format ""))
 
   (with-eval-after-load 'emms-player-mpd
-    (custom-set-variables
-     `(emms-player-mpd-music-directory ,(expand-file-name "~/Music"))
-     '(emms-player-mpd-server-name "localhost")
-     '(emms-player-mpd-server-port "6600")
-     '(emms-player-mpd-verbose t)))
+    (setopt emms-player-mpd-music-directory (expand-file-name "~/Music")
+            emms-player-mpd-server-name "localhost"
+            emms-player-mpd-server-port "6600"
+            emms-player-mpd-verbose t))
 
   (with-eval-after-load 'emms-player-mpv
-    (custom-set-variables
-     '(emms-player-mpv-ipc-method 'ipc-server)
-     '(emms-player-mpv-update-metadata t)))
+    (setopt emms-player-mpv-ipc-method 'ipc-server
+            emms-player-mpv-update-metadata t))
 
   (with-eval-after-load 'emms-playing-time
-    (custom-set-variables
-     '(emms-playing-time-display-format " %s ")))
+    (setopt emms-playing-time-display-format " %s "))
 
   (with-eval-after-load 'emms-playlist-mode
-    (custom-set-variables
-     '(emms-playlist-mode-center-when-go t)))
+    (setopt emms-playlist-mode-center-when-go t))
 
   (with-eval-after-load 'emms-streams
-    (custom-set-variables
-     `(emms-streams-file
-       ,(no-littering-expand-etc-file-name "emms/streams.emms")))))
+    (setopt emms-streams-file
+            (no-littering-expand-etc-file-name "emms/streams.emms"))))
 #+end_src
 
 *** Hiding spurious buffers