diff --git a/emacs/coolj.el b/emacs/coolj.el
index 0385872f..b3e314f0 100644
--- a/emacs/coolj.el
+++ b/emacs/coolj.el
@@ -25,13 +25,13 @@
 
 ;;; Commentary:
 
-;;; This is a simple derivative of some functionality from
-;;; `longlines.el'. The key difference is that this version will
-;;; insert a prefix at the head of each wrapped line. The prefix is
-;;; calculated from the originating long line.
+;; This is a simple derivative of some functionality from
+;; `longlines.el'. The key difference is that this version will
+;; insert a prefix at the head of each wrapped line. The prefix is
+;; calculated from the originating long line.
 
-;;; No minor-mode is provided, the caller is expected to call
-;;; `coolj-wrap-region' to wrap the region of interest.
+;; No minor-mode is provided, the caller is expected to call
+;; `coolj-wrap-region' to wrap the region of interest.
 
 ;;; Code:
 
diff --git a/emacs/notmuch-address.el b/emacs/notmuch-address.el
index 71985ed7..bf29c3a0 100644
--- a/emacs/notmuch-address.el
+++ b/emacs/notmuch-address.el
@@ -25,9 +25,11 @@
 (require 'notmuch-parser)
 (require 'notmuch-lib)
 (require 'notmuch-company)
-;;
+
 (declare-function company-manual-begin "company")
 
+;;; Cache internals
+
 (defvar notmuch-address-last-harvest 0
   "Time of last address harvest.")
 
@@ -47,6 +49,8 @@ If the hash is not present it attempts to load a saved hash."
   (or notmuch-address-full-harvest-finished
       (notmuch-address--load-address-hash)))
 
+;;; Options
+
 (defcustom notmuch-address-command 'internal
   "Determines how address completion candidates are generated.
 
@@ -133,6 +137,14 @@ matching `notmuch-address-completion-headers-regexp'."
   :group 'notmuch-address
   :group 'notmuch-hooks)
 
+(defcustom notmuch-address-use-company t
+  "If available, use company mode for address completion."
+  :type 'boolean
+  :group 'notmuch-send
+  :group 'notmuch-address)
+
+;;; Setup
+
 (defun notmuch-address-selection-function (prompt collection initial-input)
   "Call (`completing-read'
       PROMPT COLLECTION nil nil INITIAL-INPUT 'notmuch-address-history)"
@@ -147,12 +159,6 @@ matching `notmuch-address-completion-headers-regexp'."
 (defun notmuch-address-message-insinuate ()
   (message "calling notmuch-address-message-insinuate is no longer needed"))
 
-(defcustom notmuch-address-use-company t
-  "If available, use company mode for address completion."
-  :type 'boolean
-  :group 'notmuch-send
-  :group 'notmuch-address)
-
 (defun notmuch-address-setup ()
   (let* ((setup-company (and notmuch-address-use-company
 			     (require 'company nil t)))
@@ -178,6 +184,8 @@ toggles the setting in this buffer."
 	(kill-local-variable 'company-idle-delay)
       (setq-local company-idle-delay nil))))
 
+;;; Completion
+
 (defun notmuch-address-matching (substring)
   "Returns a list of completion candidates matching SUBSTRING.
 The candidates are taken from `notmuch-address-completions'."
@@ -250,6 +258,8 @@ requiring external commands."
 	(ding))))
    (t nil)))
 
+;;; Harvest
+
 (defun notmuch-address-harvest-addr (result)
   (let ((name-addr (plist-get result :name-addr)))
     (puthash name-addr t notmuch-address-completions)))
@@ -406,7 +416,7 @@ appear to be an address savefile.  Not overwriting."
 	       (setq notmuch-address-full-harvest-finished t))
 	   (setq notmuch-address-last-harvest 0)))))))
 
-;;
+;;; Standalone completion
 
 (defun notmuch-address-from-minibuffer (prompt)
   (if (not notmuch-address-command)
@@ -425,7 +435,7 @@ appear to be an address savefile.  Not overwriting."
       (let ((minibuffer-local-map rmap))
 	(read-string prompt)))))
 
-;;
+;;; _
 
 (provide 'notmuch-address)
 
diff --git a/emacs/notmuch-company.el b/emacs/notmuch-company.el
index b50e73c8..4439cc15 100644
--- a/emacs/notmuch-company.el
+++ b/emacs/notmuch-company.el
@@ -102,7 +102,6 @@
        (run-hook-with-args 'notmuch-address-post-completion-functions arg))
       (no-cache t))))
 
-
 (provide 'notmuch-company)
 
 ;;; notmuch-company.el ends here
diff --git a/emacs/notmuch-compat.el b/emacs/notmuch-compat.el
index 2975f4c2..c4e07780 100644
--- a/emacs/notmuch-compat.el
+++ b/emacs/notmuch-compat.el
@@ -41,8 +41,6 @@
 (unless (fboundp 'message--fold-long-headers)
   (add-hook 'message-header-hook 'notmuch-message--fold-long-headers))
 
-;; End of compatibility functions
-
 (provide 'notmuch-compat)
 
 ;;; notmuch-compat.el ends here
diff --git a/emacs/notmuch-crypto.el b/emacs/notmuch-crypto.el
index 9e6f3a9d..6d2d35a5 100644
--- a/emacs/notmuch-crypto.el
+++ b/emacs/notmuch-crypto.el
@@ -26,6 +26,8 @@
 
 (declare-function notmuch-show-get-message-id "notmuch-show" (&optional bare))
 
+;;; Options
+
 (defcustom notmuch-crypto-process-mime t
   "Whether to process cryptographic MIME parts.
 
@@ -55,6 +57,8 @@ mode."
   :type 'string
   :group 'notmuch-crypto)
 
+;;; Faces
+
 (defface notmuch-crypto-part-header
   '((((class color)
       (background dark))
@@ -96,6 +100,8 @@ mode."
   :group 'notmuch-crypto
   :group 'notmuch-faces)
 
+;;; Functions
+
 (define-button-type 'notmuch-crypto-status-button-type
   'action (lambda (button) (message (button-get button 'help-echo)))
   'follow-link t
@@ -259,7 +265,7 @@ corresponding key when the status button is pressed."
    'mouse-face 'notmuch-crypto-decryption)
   (insert "\n"))
 
-;;
+;;; _
 
 (provide 'notmuch-crypto)
 
diff --git a/emacs/notmuch-draft.el b/emacs/notmuch-draft.el
index f928be87..9ce9e736 100644
--- a/emacs/notmuch-draft.el
+++ b/emacs/notmuch-draft.el
@@ -31,6 +31,8 @@
 (declare-function notmuch-show-get-message-id "notmuch-show" (&optional bare))
 (declare-function notmuch-message-mode "notmuch-mua")
 
+;;; Options
+
 (defgroup notmuch-draft nil
   "Saving and editing drafts in Notmuch."
   :group 'notmuch)
@@ -85,6 +87,8 @@ like they are intended to be sent encrypted
   :group 'notmuch-draft
   :group 'notmuch-crypto)
 
+;;; Internal
+
 (defvar notmuch-draft-encryption-tag-regex
   "<#\\(part encrypt\\|secure.*mode=.*encrypt>\\)"
   "Regular expression matching mml tags indicating encryption of part or message.")
@@ -169,6 +173,8 @@ Really save and index an unencrypted copy? ")
   ;; but notmuch doesn't want that form, so remove them.
   (concat "draft-" (substring (message-make-message-id) 1 -1)))
 
+;;; Commands
+
 (defun notmuch-draft-save ()
   "Save the current draft message in the notmuch database.
 
@@ -226,6 +232,7 @@ applied to newly inserted messages)."
 
 (defun notmuch-draft-resume (id)
   "Resume editing of message with id ID."
+  ;; Used by command `notmuch-show-resume-message'.
   (let* ((tags (process-lines notmuch-command "search" "--output=tags"
 			      "--exclude=false" id))
 	 (draft (equal tags (notmuch-update-tags tags notmuch-draft-tags))))
@@ -265,10 +272,10 @@ applied to newly inserted messages)."
       ;; message is resaved or sent.
       (setq notmuch-draft-id (and draft id)))))
 
+;;; _
 
 (add-hook 'message-send-hook 'notmuch-draft--mark-deleted)
 
-
 (provide 'notmuch-draft)
 
 ;;; notmuch-draft.el ends here
diff --git a/emacs/notmuch-hello.el b/emacs/notmuch-hello.el
index 7bc713f3..28ffedd9 100644
--- a/emacs/notmuch-hello.el
+++ b/emacs/notmuch-hello.el
@@ -37,6 +37,8 @@
 		  (&optional query query-context target buffer-name open-target))
 
 
+;;; Options
+
 (defun notmuch-saved-search-get (saved-search field)
   "Get FIELD from SAVED-SEARCH.
 
@@ -192,6 +194,8 @@ fields of the search."
 (defvar notmuch-hello-indent 4
   "How much to indent non-headers.")
 
+(defimage notmuch-hello-logo ((:type png :file "notmuch-logo.png")))
+
 (defcustom notmuch-show-logo t
   "Should the notmuch logo be shown?"
   :type 'boolean
@@ -367,23 +371,15 @@ supported for \"Customized queries section\" items."
   :group 'notmuch-hello
   :type 'boolean)
 
+;;; Internal variables
+
 (defvar notmuch-hello-hidden-sections nil
   "List of sections titles whose contents are hidden.")
 
 (defvar notmuch-hello-first-run t
   "True if `notmuch-hello' is run for the first time, set to nil afterwards.")
 
-(defun notmuch-hello-nice-number (n)
-  (let (result)
-    (while (> n 0)
-      (push (% n 1000) result)
-      (setq n (/ n 1000)))
-    (setq result (or result '(0)))
-    (apply #'concat
-	   (number-to-string (car result))
-	   (mapcar (lambda (elem)
-		     (format "%s%03d" notmuch-hello-thousands-separator elem))
-		   (cdr result)))))
+;;; Widgets for inserters
 
 (define-widget 'notmuch-search-item 'item
   "A recent search."
@@ -419,6 +415,8 @@ supported for \"Customized queries section\" items."
 	  1    ; for the space before the [del] button
 	  5))) ; for the [del] button
 
+;;; Widget actions
+
 (defun notmuch-hello-search (widget &rest _event)
   (let ((search (widget-value widget)))
     (when search
@@ -451,6 +449,13 @@ supported for \"Customized queries section\" items."
 	    (delete search notmuch-search-history)))
     (notmuch-hello-update)))
 
+;;; Button utilities
+
+;; `notmuch-hello-query-counts', `notmuch-hello-nice-number' and
+;; `notmuch-hello-insert-buttons' are used outside this section.
+;; All other functions that are defined in this section are only
+;; used by these two functions.
+
 (defun notmuch-hello-longest-label (searches-alist)
   (or (cl-loop for elem in searches-alist
 	       maximize (length (notmuch-saved-search-get elem :name)))
@@ -585,6 +590,18 @@ the CLI and emacs interface."))
 	   (list (plist-put elem-plist :count message-count)))))
      query-list)))
 
+(defun notmuch-hello-nice-number (n)
+  (let (result)
+    (while (> n 0)
+      (push (% n 1000) result)
+      (setq n (/ n 1000)))
+    (setq result (or result '(0)))
+    (apply #'concat
+	   (number-to-string (car result))
+	   (mapcar (lambda (elem)
+		     (format "%s%03d" notmuch-hello-thousands-separator elem))
+		   (cdr result)))))
+
 (defun notmuch-hello-insert-buttons (searches)
   "Insert buttons for SEARCHES.
 
@@ -639,7 +656,7 @@ with `notmuch-hello-query-counts'."
     (unless (eq (% count tags-per-line) 0)
       (widget-insert "\n"))))
 
-(defimage notmuch-hello-logo ((:type png :file "notmuch-logo.png")))
+;;; Mode
 
 (defun notmuch-hello-update ()
   "Update the notmuch-hello buffer."
@@ -723,6 +740,8 @@ Complete list of currently available key bindings:
   ;;(setq buffer-read-only t)
   )
 
+;;; Inserters
+
 (defun notmuch-hello-generate-tag-alist (&optional hide-tags)
   "Return an alist from tags to queries to display in the all-tags section."
   (cl-mapcan (lambda (tag)
@@ -922,6 +941,8 @@ following:
     (let ((fill-column (- (window-width) notmuch-hello-indent)))
       (center-region start (point)))))
 
+;;; Hello!
+
 ;;;###autoload
 (defun notmuch-hello (&optional no-display)
   "Run notmuch and display saved searches, known tags, etc."
@@ -973,7 +994,7 @@ following:
   (run-hooks 'notmuch-hello-refresh-hook)
   (setq notmuch-hello-first-run nil))
 
-;;
+;;; _
 
 (provide 'notmuch-hello)
 
diff --git a/emacs/notmuch-jump.el b/emacs/notmuch-jump.el
index ff622055..7a27b6b3 100644
--- a/emacs/notmuch-jump.el
+++ b/emacs/notmuch-jump.el
@@ -198,8 +198,6 @@ buffer."
 		 (exit-minibuffer)))))))
     map))
 
-;;
-
 (provide 'notmuch-jump)
 
 ;;; notmuch-jump.el ends here
diff --git a/emacs/notmuch-lib.el b/emacs/notmuch-lib.el
index 0e235fa3..0b698d59 100644
--- a/emacs/notmuch-lib.el
+++ b/emacs/notmuch-lib.el
@@ -33,6 +33,8 @@
   (defconst notmuch-emacs-version "unknown"
     "Placeholder variable when notmuch-version.el[c] is not available."))
 
+;;; Groups
+
 (defgroup notmuch nil
   "Notmuch mail reader for Emacs."
   :group 'mail)
@@ -78,6 +80,8 @@
   "Graphical attributes for displaying text"
   :group 'notmuch)
 
+;;; Options
+
 (defcustom notmuch-command "notmuch"
   "Name of the notmuch binary.
 
@@ -125,11 +129,6 @@ the user's needs:
 		 (string :tag "Custom script"))
   :group 'notmuch-external)
 
-;;
-
-(defvar notmuch-search-history nil
-  "Variable to store notmuch searches history.")
-
 (defcustom notmuch-archive-tags '("-inbox")
   "List of tag changes to apply to a message or a thread when it is archived.
 
@@ -144,6 +143,11 @@ For example, if you wanted to remove an \"inbox\" tag and add an
   :group 'notmuch-search
   :group 'notmuch-show)
 
+;;; Variables
+
+(defvar notmuch-search-history nil
+  "Variable to store notmuch searches history.")
+
 (defvar notmuch-common-keymap
   (let ((map (make-sparse-keymap)))
     (define-key map "?" 'notmuch-help)
@@ -177,6 +181,8 @@ For example, if you wanted to remove an \"inbox\" tag and add an
 		  (select-window (posn-window (event-start last-input-event)))
 		  (button-activate button)))
 
+;;; CLI Utilities
+
 (defun notmuch-command-to-string (&rest args)
   "Synchronously invoke \"notmuch\" with the given list of arguments.
 
@@ -234,6 +240,8 @@ displays both values separately."
 	       (concat cli-version
 		       " (emacs mua version " notmuch-emacs-version ")")))))
 
+;;; Notmuch Configuration
+
 (defun notmuch-config-get (item)
   "Return a value from the notmuch configuration."
   (let* ((val (notmuch-command-to-string "config" "get" item))
@@ -263,6 +271,8 @@ displays both values separately."
 (defun notmuch-user-emails ()
   (cons (notmuch-user-primary-email) (notmuch-user-other-email)))
 
+;;; Commands
+
 (defun notmuch-poll ()
   "Run \"notmuch new\" or an external script to import mail.
 
@@ -287,6 +297,8 @@ it, in which case it is killed."
       (bury-buffer)
     (kill-buffer)))
 
+;;; Describe Key Bindings
+
 (defun notmuch-prefix-key-description (key)
   "Given a prefix key code, return a human-readable string representation.
 
@@ -297,7 +309,6 @@ This is basically just `format-kbd-macro' but we also convert ESC to M-."
 	"M-"
       (concat desc " "))))
 
-
 (defun notmuch-describe-key (actual-key binding prefix ua-keys tail)
   "Prepend cons cells describing prefix-arg ACTUAL-KEY and ACTUAL-KEY to TAIL.
 
@@ -435,6 +446,8 @@ of its command symbol."
 	  (insert desc)))
       (pop-to-buffer (help-buffer)))))
 
+;;; Refreshing Buffers
+
 (defvar-local notmuch-buffer-refresh-function nil
   "Function to call to refresh the current buffer.")
 
@@ -466,6 +479,8 @@ be displayed."
 	(with-current-buffer buffer
 	  (notmuch-refresh-this-buffer))))))
 
+;;; String Utilities
+
 (defun notmuch-prettify-subject (subject)
   ;; This function is used by `notmuch-search-process-filter' which
   ;; requires that we not disrupt its' matching state.
@@ -509,8 +524,6 @@ This replaces spaces, percents, and double quotes in STR with
   (replace-regexp-in-string
    "[ %\"]" (lambda (match) (format "%%%02x" (aref match 0))) str))
 
-;;
-
 (defun notmuch-common-do-stash (text)
   "Common function to stash text in kill ring, and display in minibuffer."
   (if text
@@ -522,7 +535,7 @@ This replaces spaces, percents, and double quotes in STR with
     (kill-new "")
     (message "Nothing to stash!")))
 
-;;
+;;; Generic Utilities
 
 (defun notmuch-plist-delete (plist property)
   (let* ((xplist (cons nil plist))
@@ -533,6 +546,8 @@ This replaces spaces, percents, and double quotes in STR with
       (setq pred (cddr pred)))
     (cdr xplist)))
 
+;;; MML Utilities
+
 (defun notmuch-match-content-type (t1 t2)
   "Return t if t1 and t2 are matching content types, taking wildcards into account."
   (let ((st1 (split-string t1 "/"))
@@ -673,6 +688,8 @@ current buffer, if possible."
 	    (mm-display-part handle)
 	    t))))))
 
+;;; Generic Utilities
+
 ;; Converts a plist of headers to an alist of headers. The input plist should
 ;; have symbols of the form :Header as keys, and the resulting alist will have
 ;; symbols of the form 'Header as keys.
@@ -739,6 +756,8 @@ returned by FUNC."
       (put-text-property start next prop (funcall func value) object)
       (setq start next))))
 
+;;; Running Notmuch
+
 (defun notmuch-logged-error (msg &optional extra)
   "Log MSG and EXTRA to *Notmuch errors* and signal MSG.
 
@@ -967,6 +986,8 @@ status."
 
 (defvar-local notmuch-show-process-crypto nil)
 
+;;; Generic Utilities
+
 (defun notmuch-interactive-region ()
   "Return the bounds of the current interactive region.
 
@@ -981,6 +1002,8 @@ region if the region is active, or both `point' otherwise."
   'notmuch-interactive-region
   "notmuch 0.29")
 
+;;; _
+
 (provide 'notmuch-lib)
 
 ;;; notmuch-lib.el ends here
diff --git a/emacs/notmuch-maildir-fcc.el b/emacs/notmuch-maildir-fcc.el
index 32b8100e..5de03cc2 100644
--- a/emacs/notmuch-maildir-fcc.el
+++ b/emacs/notmuch-maildir-fcc.el
@@ -29,6 +29,8 @@
 
 (defvar notmuch-maildir-fcc-count 0)
 
+;;; Options
+
 (defcustom notmuch-fcc-dirs "sent"
   "Determines the Fcc Header which says where to save outgoing mail.
 
@@ -83,8 +85,7 @@ directory if it does not exist yet when sending a mail."
 		 (const :tag "Use simple fcc" nil))
   :group 'notmuch-send)
 
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; Functions which set up the fcc header in the message buffer.
+;;; Functions which set up the fcc header in the message buffer.
 
 (defun notmuch-fcc-header-setup ()
   "Add an Fcc header to the current message buffer.
@@ -142,9 +143,7 @@ Insert header anyway? " subdir)))
 		subdir
 	      (concat (notmuch-database-path) "/" subdir))))))
 
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; Functions for saving a message either using notmuch insert or file
-;; fcc. First functions common to the two cases.
+;;; Functions for saving a message using either method.
 
 (defmacro with-temporary-notmuch-message-buffer (&rest body)
   "Set-up a temporary copy of the current message-mode buffer."
@@ -204,8 +203,7 @@ normal fcc."
       (notmuch-maildir-fcc-with-notmuch-insert fcc-header)
     (notmuch-maildir-fcc-file-fcc fcc-header)))
 
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; Functions for saving a message using notmuch insert.
+;;; Functions for saving a message using notmuch insert.
 
 (defun notmuch-maildir-notmuch-insert-current-buffer (folder &optional create tags)
   "Use notmuch insert to put the current buffer in the database.
@@ -251,9 +249,7 @@ If CREATE is non-nil then create the folder if necessary."
 	   (?e (notmuch-maildir-fcc-with-notmuch-insert
 		(read-from-minibuffer "Fcc header: " fcc-header)))))))))
 
-
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; Functions for saving a message using file fcc.
+;;; Functions for saving a message using file fcc.
 
 (defun notmuch-maildir-fcc-host-fixer (hostname)
   (replace-regexp-in-string "/\\|:"
@@ -362,6 +358,8 @@ return t if successful, and nil otherwise."
 	  (delete-file (concat destdir "/tmp/" msg-id))))
       t)))
 
+;;; _
+
 (provide 'notmuch-maildir-fcc)
 
 ;;; notmuch-maildir-fcc.el ends here
diff --git a/emacs/notmuch-mua.el b/emacs/notmuch-mua.el
index c38cb5aa..6fe5f6d0 100644
--- a/emacs/notmuch-mua.el
+++ b/emacs/notmuch-mua.el
@@ -38,7 +38,7 @@
 (declare-function notmuch-draft-postpone "notmuch-draft" ())
 (declare-function notmuch-draft-save "notmuch-draft" ())
 
-;;
+;;; Options
 
 (defcustom notmuch-mua-send-hook nil
   "Hook run before sending messages."
@@ -120,7 +120,7 @@ to `notmuch-mua-send-hook'."
   :type 'regexp
   :group 'notmuch-send)
 
-;;
+;;; Various functions
 
 (defun notmuch-mua-attachment-check ()
   "Signal an error if the message text indicates that an
@@ -215,6 +215,8 @@ Typically this is added to `notmuch-mua-send-hook'."
   (funcall original-func header references)
   (unless (bolp) (insert "\n")))
 
+;;; Mua reply
+
 (defun notmuch-mua-reply (query-string &optional sender reply-all)
   (let ((args '("reply" "--format=sexp" "--format-version=4"))
 	(process-crypto notmuch-show-process-crypto)
@@ -318,6 +320,8 @@ Typically this is added to `notmuch-mua-send-hook'."
   (message-goto-body)
   (set-buffer-modified-p nil))
 
+;;; Mode and keymap
+
 (defvar notmuch-message-mode-map
   (let ((map (make-sparse-keymap)))
     (define-key map (kbd "C-c C-c") #'notmuch-mua-send-and-exit)
@@ -333,6 +337,8 @@ Typically this is added to `notmuch-mua-send-hook'."
 
 (put 'notmuch-message-mode 'flyspell-mode-predicate 'mail-mode-flyspell-verify)
 
+;;; New messages
+
 (defun notmuch-mua-pop-to-buffer (name switch-function)
   "Pop to buffer NAME, and warn if it already exists and is modified.
 Like `message-pop-to-buffer' but enable `notmuch-message-mode'
@@ -528,6 +534,8 @@ will be addressed to all recipients of the source message."
     (notmuch-mua-reply query-string sender reply-all)
     (deactivate-mark)))
 
+;;; Checks
+
 (defun notmuch-mua-check-no-misplaced-secure-tag ()
   "Query user if there is a misplaced secure mml tag.
 
@@ -570,6 +578,8 @@ The <#secure> tag at the start of the body is not followed by a
 newline. It is likely that the message will be sent unsigned and
 unencrypted.  Really send? "))))
 
+;;; Finishing commands
+
 (defun notmuch-mua-send-common (arg &optional exit)
   (interactive "P")
   (run-hooks 'notmuch-mua-send-hook)
@@ -593,7 +603,7 @@ unencrypted.  Really send? "))))
   (interactive)
   (message-kill-buffer))
 
-;;
+;;; _
 
 (define-mail-user-agent 'notmuch-user-agent
   'notmuch-mua-mail 'notmuch-mua-send-and-exit
@@ -603,8 +613,6 @@ unencrypted.  Really send? "))))
 ;; composing a message.
 (notmuch-mua-add-more-hidden-headers)
 
-;;
-
 (provide 'notmuch-mua)
 
 ;;; notmuch-mua.el ends here
diff --git a/emacs/notmuch-print.el b/emacs/notmuch-print.el
index 6dd9f775..d7b2fcce 100644
--- a/emacs/notmuch-print.el
+++ b/emacs/notmuch-print.el
@@ -25,6 +25,8 @@
 
 (declare-function notmuch-show-get-prop "notmuch-show" (prop &optional props))
 
+;;; Options
+
 (defcustom notmuch-print-mechanism 'notmuch-print-lpr
   "How should printing be done?"
   :group 'notmuch-show
@@ -36,7 +38,7 @@
 	  (function :tag "Use muttprint then evince" notmuch-print-muttprint/evince)
 	  (function :tag "Using a custom function")))
 
-;; Utility functions:
+;;; Utility functions
 
 (defun notmuch-print-run-evince (file)
   "View FILE using 'evince'."
@@ -54,7 +56,7 @@ Optional OUTPUT allows passing a list of flags to muttprint."
 	 "--printed-headers" "Date_To_From_CC_Newsgroups_*Subject*_/Tags/"
 	 output))
 
-;; User-visible functions:
+;;; User-visible functions
 
 (defun notmuch-print-lpr (msg)
   "Print a message buffer using lpr."
@@ -91,6 +93,8 @@ Optional OUTPUT allows passing a list of flags to muttprint."
   (set-buffer-modified-p nil)
   (funcall notmuch-print-mechanism msg))
 
+;;; _
+
 (provide 'notmuch-print)
 
 ;;; notmuch-print.el ends here
diff --git a/emacs/notmuch-query.el b/emacs/notmuch-query.el
index 3cfccbc3..72ddd2ce 100644
--- a/emacs/notmuch-query.el
+++ b/emacs/notmuch-query.el
@@ -23,6 +23,8 @@
 
 (require 'notmuch-lib)
 
+;;; Basic query function
+
 (defun notmuch-query-get-threads (search-terms)
   "Return a list of threads of messages matching SEARCH-TERMS.
 
@@ -35,8 +37,7 @@ is a possibly empty forest of replies."
     (setq args (append args search-terms))
     (apply #'notmuch-call-notmuch-sexp args)))
 
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; Mapping functions across collections of messages.
+;;; Mapping functions across collections of messages
 
 (defun notmuch-query-map-aux  (mapper function seq)
   "Private function to do the actual mapping and flattening."
@@ -64,8 +65,7 @@ Flatten results to a list.  See the function
 `notmuch-query-get-threads' for more information."
   (cons (funcall fn (car tree)) (notmuch-query-map-forest fn (cadr tree))))
 
-;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; Predefined queries
+;;; Predefined queries
 
 (defun notmuch-query-get-message-ids (&rest search-terms)
   "Return a list of message-ids of messages that match SEARCH-TERMS."
diff --git a/emacs/notmuch-show.el b/emacs/notmuch-show.el
index 056c4e30..7dfbb327 100644
--- a/emacs/notmuch-show.el
+++ b/emacs/notmuch-show.el
@@ -59,6 +59,8 @@
 (declare-function notmuch-read-query "notmuch" (prompt))
 (declare-function notmuch-draft-resume "notmuch-draft" (id))
 
+;;; Options
+
 (defcustom notmuch-message-headers '("Subject" "To" "Cc" "Date")
   "Headers that should be shown in a message, in this order.
 
@@ -162,6 +164,8 @@ indentation."
   :type '(choice (const nil) regexp)
   :group 'notmuch-show)
 
+;;; Variables
+
 (defvar-local notmuch-show-thread-id nil)
 
 (defvar-local notmuch-show-parent-buffer nil)
@@ -182,6 +186,8 @@ handlers is discarded. When set to t the stdout and stderr from
 each attachment handler is logged in buffers with names beginning
 \" *notmuch-part*\".")
 
+;;; Options
+
 (defcustom notmuch-show-stash-mlarchive-link-alist
   '(("Gmane" . "https://mid.gmane.org/")
     ("MARC" . "https://marc.info/?i=")
@@ -260,6 +266,8 @@ position of the message in the thread."
   :type 'boolean
   :group 'notmuch-show)
 
+;;; Utilities
+
 (defmacro with-current-notmuch-show-message (&rest body)
   "Evaluate body with current buffer set to the text of current message."
   `(save-excursion
@@ -275,6 +283,8 @@ position of the message in the thread."
   "Enable Visual Line mode."
   (visual-line-mode t))
 
+;;; Commands
+
 ;; DEPRECATED in Notmuch 0.16 since we now have convenient part
 ;; commands.  We'll keep the command around for a version or two in
 ;; case people want to bind it themselves.
@@ -355,6 +365,8 @@ operation on the contents of the current buffer."
   (interactive)
   (notmuch-show-with-message-as-text 'notmuch-print-message))
 
+;;; Headers
+
 (defun notmuch-show-fontify-header ()
   (let ((face (cond
 	       ((looking-at "[Tt]o:")
@@ -493,6 +505,8 @@ message at DEPTH in the current thread."
 	(narrow-to-region start (point-max))
 	(run-hooks 'notmuch-show-markup-headers-hook)))))
 
+;;; Parts
+
 (define-button-type 'notmuch-show-part-button-type
   'action 'notmuch-show-part-button-default
   'follow-link t
@@ -548,7 +562,7 @@ message at DEPTH in the current thread."
 	      (overlay-put overlay 'invisible (not show))
 	      t)))))))
 
-;; Part content ID handling
+;;; Part content ID handling
 
 (defvar notmuch-show--cids nil
   "Alist from raw content ID to (MSG PART).")
@@ -811,7 +825,8 @@ will return nil if the CID is unknown or cannot be retrieved."
 	  (gnus-blocked-images notmuch-show-text/html-blocked-images))
       (notmuch-show-insert-part-*/* msg part content-type nth depth button))))
 
-;; These functions are used by notmuch-show--insert-part-text/html-shr
+;;; Functions used by notmuch-show--insert-part-text/html-shr
+
 (declare-function libxml-parse-html-region "xml.c")
 (declare-function shr-insert-document "shr")
 
@@ -836,7 +851,7 @@ will return nil if the CID is unknown or cannot be retrieved."
   (notmuch-mm-display-part-inline msg part content-type notmuch-show-process-crypto)
   t)
 
-;; Functions for determining how to handle MIME parts.
+;;; Functions for determining how to handle MIME parts.
 
 (defun notmuch-show-handlers-for (content-type)
   "Return a list of content handlers for a part of type CONTENT-TYPE."
@@ -852,7 +867,7 @@ will return nil if the CID is unknown or cannot be retrieved."
 		(intern (concat "notmuch-show-insert-part-" content-type))))
     result))
 
-;; 
+;;; Parts
 
 (defun notmuch-show-insert-bodypart-internal (msg part content-type nth depth button)
   ;; Run the handlers until one of them succeeds.
@@ -1098,6 +1113,8 @@ is t, hide the part initially and show the button."
     (notmuch-show-message-visible msg (and (plist-get msg :match)
 					   (not (plist-get msg :excluded))))))
 
+;;; Toggle commands
+
 (defun notmuch-show-toggle-process-crypto ()
   "Toggle the processing of cryptographic MIME parts."
   (interactive)
@@ -1126,6 +1143,8 @@ is t, hide the part initially and show the button."
 	     "Content is not indented."))
   (notmuch-show-refresh-view))
 
+;;; Main insert functions
+
 (defun notmuch-show-insert-tree (tree depth)
   "Insert the message tree TREE at depth DEPTH in the current thread."
   (let ((msg (car tree))
@@ -1143,6 +1162,8 @@ is t, hide the part initially and show the button."
   "Insert the forest of threads FOREST."
   (mapc (lambda (thread) (notmuch-show-insert-thread thread 0)) forest))
 
+;;; Link buttons
+
 (defvar notmuch-id-regexp
   (concat
    ;; Match the id: prefix only if it begins a word (to disallow, for
@@ -1203,6 +1224,8 @@ buttons for a corresponding notmuch search."
 			  'help-echo "Mouse-1, RET: search for this message"
 			  'face goto-address-mail-face)))))
 
+;;; Show command
+
 ;;;###autoload
 (defun notmuch-show (thread-id &optional elide-toggle parent-buffer query-context buffer-name)
   "Run \"notmuch show\" with the given thread ID and display results.
@@ -1325,6 +1348,8 @@ If no messages match the query return NIL."
     ;; Report back to the caller whether any messages matched.
     forest))
 
+;;; Refresh command
+
 (defun notmuch-show-capture-state ()
   "Capture the state of the current buffer.
 
@@ -1399,6 +1424,8 @@ reset based on the original query."
       (ding)
       (message "Refreshing the buffer resulted in no messages!"))))
 
+;;; Keymaps
+
 (defvar notmuch-show-stash-map
   (let ((map (make-sparse-keymap)))
     (define-key map "c" 'notmuch-show-stash-cc)
@@ -1479,6 +1506,8 @@ reset based on the original query."
     map)
   "Keymap for \"notmuch show\" buffers.")
 
+;;; Mode
+
 (define-derived-mode notmuch-show-mode fundamental-mode "notmuch-show"
   "Major mode for viewing a thread with notmuch.
 
@@ -1515,6 +1544,8 @@ All currently available key bindings:
   (setq imenu-extract-index-name-function
 	#'notmuch-show-imenu-extract-index-name-function))
 
+;;; Tree commands
+
 (defun notmuch-tree-from-show-current-query ()
   "Call notmuch tree with the current query."
   (interactive)
@@ -1529,17 +1560,14 @@ All currently available key bindings:
 		      notmuch-show-query-context
 		      (notmuch-show-get-message-id)))
 
+;;; Movement related functions.
+
 (defun notmuch-show-move-to-message-top ()
   (goto-char (notmuch-show-message-top)))
 
 (defun notmuch-show-move-to-message-bottom ()
   (goto-char (notmuch-show-message-bottom)))
 
-(defun notmuch-show-message-adjust ()
-  (recenter 0))
-
-;; Movement related functions.
-
 ;; There's some strangeness here where a text property applied to a
 ;; region a->b is not found when point is at b. We walk backwards
 ;; until finding the property.
@@ -1583,8 +1611,7 @@ effects."
     (cl-loop do (funcall function)
 	     while (notmuch-show-goto-message-next))))
 
-;; Functions relating to the visibility of messages and their
-;; components.
+;;; Functions relating to the visibility of messages and their components.
 
 (defun notmuch-show-message-visible (props visible-p)
   (overlay-put (plist-get props :message-overlay) 'invisible (not visible-p))
@@ -1594,8 +1621,7 @@ effects."
   (overlay-put (plist-get props :headers-overlay) 'invisible (not visible-p))
   (notmuch-show-set-prop :headers-visible visible-p props))
 
-;; Functions for setting and getting attributes of the current
-;; message.
+;;; Functions for setting and getting attributes of the current message.
 
 (defun notmuch-show-set-message-properties (props)
   (save-excursion
@@ -1768,8 +1794,7 @@ Reshows the current thread with matches defined by the new query-string."
     (notmuch-show-refresh-view t)
     (notmuch-show-goto-message msg-id)))
 
-;; Functions for getting attributes of several messages in the current
-;; thread.
+;;; Functions for getting attributes of several messages in the current thread.
 
 (defun notmuch-show-get-message-ids-for-open-messages ()
   "Return a list of all id: queries for open messages in the current thread."
@@ -1783,7 +1808,7 @@ Reshows the current thread with matches defined by the new query-string."
 	(setq done (not (notmuch-show-goto-message-next))))
       message-ids)))
 
-;; Commands typically bound to keys.
+;;; Commands typically bound to keys.
 
 (defun notmuch-show-advance ()
   "Advance through thread.
@@ -1911,6 +1936,9 @@ any effects from previous calls to
     (message-resend addresses)
     (notmuch-bury-or-kill-this-buffer)))
 
+(defun notmuch-show-message-adjust ()
+  (recenter 0))
+
 (defun notmuch-show-next-message (&optional pop-at-end)
   "Show the next message.
 
@@ -2381,7 +2409,7 @@ omit --in-reply-to=<Message-Id>."
 			  (list (notmuch-show-get-message-id t)) "--in-reply-to="))))
 	      " ")))
 
-;; Interactive part functions and their helpers
+;;; Interactive part functions and their helpers
 
 (defun notmuch-show-generate-part-buffer (msg part)
   "Return a temporary buffer containing the specified part's content."
@@ -2528,6 +2556,8 @@ browsing."
 	(funcall fn (completing-read prompt urls nil nil nil nil (car urls)))
       (message "No URLs found."))))
 
+;;; _
+
 (provide 'notmuch-show)
 
 ;;; notmuch-show.el ends here
diff --git a/emacs/notmuch-tag.el b/emacs/notmuch-tag.el
index 925de78c..817ea99f 100644
--- a/emacs/notmuch-tag.el
+++ b/emacs/notmuch-tag.el
@@ -37,6 +37,8 @@
 (declare-function notmuch-tree-tag "notmuch-tree" (tag-changes))
 (declare-function notmuch-jump "notmuch-jump" (action-map prompt))
 
+;;; Keys
+
 (define-widget 'notmuch-tag-key-type 'list
   "A single key tagging binding."
   :format "%v"
@@ -84,6 +86,8 @@ from TAGGING-OPERATIONS."
   :type '(repeat notmuch-tag-key-type)
   :group 'notmuch-tag)
 
+;;; Faces and Formats
+
 (define-widget 'notmuch-tag-format-type 'lazy
   "Customize widget for notmuch-tag-format and friends."
   :type '(alist :key-type (regexp :tag "Tag")
@@ -217,6 +221,8 @@ See `notmuch-tag-formats' for full documentation."
   :group 'notmuch-faces
   :type 'notmuch-tag-format-type)
 
+;;; Icons
+
 (defun notmuch-tag-format-image-data (tag data)
   "Replace TAG with image DATA, if available.
 
@@ -270,6 +276,8 @@ This can be used with `notmuch-tag-format-image-data'."
   </g>
 </svg>")
 
+;;; Format Handling
+
 (defvar notmuch-tag--format-cache (make-hash-table :test 'equal)
   "Cache of tag format lookup.  Internal to `notmuch-tag-format-tag'.")
 
@@ -347,6 +355,8 @@ changed (the normal case) are shown using formats from
      face
      t)))
 
+;;; Hooks
+
 (defcustom notmuch-before-tag-hook nil
   "Hooks that are run before tags of a message are modified.
 
@@ -369,6 +379,8 @@ the messages that were tagged."
   :options '(notmuch-hl-line-mode)
   :group 'notmuch-hooks)
 
+;;; User Input
+
 (defvar notmuch-select-tag-history nil
   "Variable to store minibuffer history for
 `notmuch-select-tag-with-completion' function.")
@@ -429,6 +441,8 @@ initial input in the minibuffer."
 		nil nil initial-input
 		'notmuch-read-tag-changes-history))))
 
+;;; Tagging
+
 (defun notmuch-update-tags (tags tag-changes)
   "Return a copy of TAGS with additions and removals from TAG-CHANGES.
 
@@ -547,7 +561,7 @@ and vice versa."
     (setq action-map (nreverse action-map))
     (notmuch-jump action-map "Tag: ")))
 
-;;
+;;; _
 
 (provide 'notmuch-tag)
 
diff --git a/emacs/notmuch-tree.el b/emacs/notmuch-tree.el
index 17863f6a..713b00da 100644
--- a/emacs/notmuch-tree.el
+++ b/emacs/notmuch-tree.el
@@ -54,6 +54,8 @@
 (defvar-local notmuch-tree-unthreaded nil
   "A buffer local copy of argument unthreaded to the function notmuch-tree.")
 
+;;; Options
+
 (defgroup notmuch-tree nil
   "Showing message and thread structure."
   :group 'notmuch)
@@ -118,7 +120,9 @@ For example:
       notmuch-unthreaded-result-format
     notmuch-tree-result-format))
 
-;; Faces for messages that match the query.
+;;; Faces
+;;;; Faces for messages that match the query
+
 (defface notmuch-tree-match-face
   '((t :inherit default))
   "Default face used in tree mode face for matching messages"
@@ -169,7 +173,8 @@ For example:
   :group 'notmuch-tree
   :group 'notmuch-faces)
 
-;; Faces for messages that do not match the query.
+;;;; Faces for messages that do not match the query
+
 (defface notmuch-tree-no-match-face
   '((t (:foreground "gray")))
   "Default face used in tree mode face for non-matching messages."
@@ -206,6 +211,8 @@ For example:
   :group 'notmuch-tree
   :group 'notmuch-faces)
 
+;;; Variables
+
 (defvar-local notmuch-tree-previous-subject
   "The subject of the most recent result shown during the async display.")
 
@@ -238,6 +245,8 @@ This is used to try and make sure we don't close the message pane
 if the user has loaded a different buffer in that window.")
 (put 'notmuch-tree-message-buffer 'permanent-local t)
 
+;;; Tree wrapper commands
+
 (defmacro notmuch-tree--define-do-in-message-window (name cmd)
   "Define NAME as a command that calls CMD interactively in the message window.
 If the message pane is closed then this command does nothing.
@@ -305,6 +314,8 @@ then NAME behaves like CMD."
  notmuch-tree-view-raw-message
  notmuch-show-view-raw-message)
 
+;;; Keymap
+
 (defvar notmuch-tree-mode-map
   (let ((map (make-sparse-keymap)))
     (set-keymap-parent map notmuch-common-keymap)
@@ -363,6 +374,8 @@ then NAME behaves like CMD."
     map)
   "Keymap for \"notmuch tree\" buffers.")
 
+;;; Message properties
+
 (defun notmuch-tree-get-message-properties ()
   "Return the properties of the current message as a plist.
 
@@ -414,6 +427,8 @@ Some useful entries are:
   (interactive)
   (notmuch-tree-get-prop :match))
 
+;;; Update display
+
 (defun notmuch-tree-refresh-result ()
   "Redisplay the current message line.
 
@@ -456,6 +471,8 @@ NOT change the database."
 	  (when (string= tree-msg-id (notmuch-show-get-message-id))
 	    (notmuch-show-update-tags new-tags)))))))
 
+;;; Commands (and some helper functions used by them)
+
 (defun notmuch-tree-tag (tag-changes)
   "Change tags for the current message."
   (interactive
@@ -835,7 +852,7 @@ buffer."
     (notmuch-tree-tag-thread
      (notmuch-tag-change-list notmuch-archive-tags unarchive))))
 
-;; Functions below here display the tree buffer itself.
+;;; Functions for displaying the tree buffer itself
 
 (defun notmuch-tree-clean-address (address)
   "Try to clean a single email ADDRESS for display. Return
@@ -1142,7 +1159,7 @@ The arguments are:
   (interactive)
   (notmuch-tree query query-context target buffer-name open-target t))
 
-;;
+;;; _
 
 (provide 'notmuch-tree)
 
diff --git a/emacs/notmuch-wash.el b/emacs/notmuch-wash.el
index ce4b9637..f371cc4c 100644
--- a/emacs/notmuch-wash.el
+++ b/emacs/notmuch-wash.el
@@ -30,7 +30,7 @@
 		  (msg part depth &optional hide))
 (defvar notmuch-show-indent-messages-width)
 
-;;
+;;; Options
 
 (defgroup notmuch-wash nil
   "Cleaning up messages for display."
@@ -130,6 +130,8 @@ or at the window width (whichever one is lower)."
 		 (integer :tag "number of characters"))
   :group 'notmuch-wash)
 
+;;; Faces
+
 (defface notmuch-wash-toggle-button
   '((t (:inherit font-lock-comment-face)))
   "Face used for buttons toggling the visibility of washed away
@@ -143,6 +145,8 @@ message parts."
   :group 'notmuch-wash
   :group 'notmuch-faces)
 
+;;; Buttons
+
 (defun notmuch-wash-toggle-invisible-action (cite-button)
   ;; Toggle overlay visibility
   (let ((overlay (button-get cite-button 'overlay)))
@@ -225,6 +229,8 @@ that PREFIX should not include a newline."
 				   :type button-type)))
 	  (overlay-put overlay 'notmuch-wash-button button))))))
 
+;;; Hook functions
+
 (defun notmuch-wash-excerpt-citations (msg depth)
   "Excerpt citations and up to one signature."
   (goto-char (point-min))
@@ -270,8 +276,6 @@ that PREFIX should not include a newline."
 	   msg sig-start-marker sig-end-marker
 	   "signature"))))))
 
-;;
-
 (defun notmuch-wash-elide-blank-lines (msg depth)
   "Elide leading, trailing and successive blank lines."
   ;; Algorithm derived from `article-strip-multiple-blank-lines' in
@@ -293,8 +297,6 @@ that PREFIX should not include a newline."
   (when (looking-at "\n")
     (delete-region (match-beginning 0) (match-end 0))))
 
-;;
-
 (defun notmuch-wash-tidy-citations (msg depth)
   "Improve the display of cited regions of a message.
 
@@ -319,8 +321,6 @@ Perform several transformations on the message body:
   (while (re-search-forward "\\(^>[> ]*\n\\)\\(^$\\|^[^>].*\\)" nil t)
     (replace-match "\\2")))
 
-;;
-
 (defun notmuch-wash-wrap-long-lines (msg depth)
   "Wrap long lines in the message.
 
@@ -342,7 +342,7 @@ the wrapped text are maintained."
 			 2)))
     (coolj-wrap-region (point-min) (point-max))))
 
-;;
+;;;; Convert Inline Patches
 
 (require 'diff-mode)
 
@@ -417,7 +417,7 @@ for error."
 	(delete-region (point-min) (point-max))
 	(notmuch-show-insert-bodypart nil part depth)))))
 
-;;
+;;; _
 
 (provide 'notmuch-wash)
 
diff --git a/emacs/notmuch.el b/emacs/notmuch.el
index bba4ca03..6a09dd38 100644
--- a/emacs/notmuch.el
+++ b/emacs/notmuch.el
@@ -80,6 +80,8 @@
 (require 'notmuch-message)
 (require 'notmuch-parser)
 
+;;; Options
+
 (defcustom notmuch-search-result-format
   `(("date" . "%12s ")
     ("count" . "%-7s ")
@@ -115,6 +117,8 @@ there will be called at other points of notmuch execution."
 (defvar notmuch-query-history nil
   "Variable to store minibuffer history for notmuch queries.")
 
+;;; Mime Utilities
+
 (defun notmuch-foreach-mime-part (function mm-handle)
   (cond ((stringp (car mm-handle))
 	 (dolist (part (cdr mm-handle))
@@ -151,6 +155,8 @@ there will be called at other points of notmuch execution."
 	    (mm-save-part p))))
    mm-handle))
 
+;;; Integrations
+
 (require 'hl-line)
 
 (defun notmuch-hl-line-mode ()
@@ -158,6 +164,8 @@ there will be called at other points of notmuch execution."
     (when hl-line-overlay
       (overlay-put hl-line-overlay 'priority 1))))
 
+;;; Options
+
 (defcustom notmuch-search-hook '(notmuch-hl-line-mode)
   "List of functions to call when notmuch displays the search results."
   :type 'hook
@@ -165,6 +173,8 @@ there will be called at other points of notmuch execution."
   :group 'notmuch-search
   :group 'notmuch-hooks)
 
+;;; Keymap
+
 (defvar notmuch-search-mode-map
   (let ((map (make-sparse-keymap)))
     (set-keymap-parent map notmuch-common-keymap)
@@ -195,6 +205,8 @@ there will be called at other points of notmuch execution."
     map)
   "Keymap for \"notmuch search\" buffers.")
 
+;;; Stashing
+
 (defvar notmuch-search-stash-map
   (let ((map (make-sparse-keymap)))
     (define-key map "i" 'notmuch-search-stash-thread-id)
@@ -214,12 +226,16 @@ there will be called at other points of notmuch execution."
   (interactive)
   (notmuch-common-do-stash (notmuch-search-get-query)))
 
+;;; Variables
+
 (defvar notmuch-search-query-string)
 (defvar notmuch-search-target-thread)
 (defvar notmuch-search-target-line)
 
 (defvar notmuch-search-disjunctive-regexp      "\\<[oO][rR]\\>")
 
+;;; Movement
+
 (defun notmuch-search-scroll-up ()
   "Move forward through search results by one window's worth."
   (interactive)
@@ -271,6 +287,8 @@ there will be called at other points of notmuch execution."
   (interactive)
   (goto-char (point-min)))
 
+;;; Faces
+
 (defface notmuch-message-summary-face
   `((((class color) (background light))
      ,@(and (>= emacs-major-version 27) '(:extend t))
@@ -356,6 +374,8 @@ This face is the default value for the \"unread\" tag in
   :group 'notmuch-search
   :group 'notmuch-faces)
 
+;;; Mode
+
 (define-derived-mode notmuch-search-mode fundamental-mode "notmuch-search"
   "Major mode displaying results of a notmuch search.
 
@@ -400,6 +420,8 @@ Complete list of currently available key bindings:
   (setq imenu-extract-index-name-function
 	#'notmuch-search-imenu-extract-index-name-function))
 
+;;; Search Results
+
 (defun notmuch-search-get-result (&optional pos)
   "Return the result object for the thread at POS (or point).
 
@@ -558,6 +580,8 @@ thread."
   (let ((message-id (notmuch-search-find-thread-id)))
     (notmuch-mua-new-reply message-id prompt-for-sender nil)))
 
+;;; Tags
+
 (defun notmuch-search-set-tags (tags &optional pos)
   (let ((new-result (plist-put (notmuch-search-get-result pos) :tags tags)))
     (notmuch-search-update-result new-result pos)))
@@ -639,6 +663,8 @@ This function advances the next thread when finished."
   (when (eq beg end)
     (notmuch-search-next-thread)))
 
+;;; Search Results
+
 (defun notmuch-search-update-result (result &optional pos)
   "Replace the result object of the thread at POS (or point) by
 RESULT and redraw it.
@@ -881,6 +907,8 @@ sets the :orig-tag property."
 	(notmuch-sexp-parse-partial-list 'notmuch-search-append-result
 					 results-buf)))))
 
+;;; Commands (and some helper functions used by them)
+
 (defun notmuch-search-tag-all (tag-changes)
   "Add/remove tags from all messages in current search buffer.
 
@@ -1132,7 +1160,7 @@ notmuch buffers exist, run `notmuch'."
 	  (pop-to-buffer-same-window first))
       (notmuch))))
 
-;;;; Imenu Support
+;;; Imenu Support
 
 (defun notmuch-search-imenu-prev-index-position-function ()
   "Move point to previous message in notmuch-search buffer.
@@ -1149,6 +1177,8 @@ beginning of the line."
 	(author (notmuch-search-find-authors)))
     (format "%s (%s)" subject author)))
 
+;;; _
+
 (setq mail-user-agent 'notmuch-user-agent)
 
 (provide 'notmuch)
diff --git a/test/test-lib.el b/test/test-lib.el
index ec16c59c..4de5b292 100644
--- a/test/test-lib.el
+++ b/test/test-lib.el
@@ -1,4 +1,4 @@
-;; test-lib.el --- auxiliary stuff for Notmuch Emacs tests.
+;;; test-lib.el --- auxiliary stuff for Notmuch Emacs tests
 ;;
 ;; Copyright © Carl Worth
 ;; Copyright © David Edmondson
@@ -20,6 +20,8 @@
 ;;
 ;; Authors: Dmitry Kurochkin <dmitry.kurochkin@gmail.com>
 
+;;; Code:
+
 (require 'cl-lib)
 
 ;; Ensure that the dynamic variables that are defined by this library