Make Emacs use ugrep when available

README.org

@@ -1347,6 +1347,45 @@ to {{{kbd(M-s d)}}} and =deadgrep-edit-mode= to {{{kbd(C-c C-w)}}}.
       (define-key deadgrep-mode-map (kbd "C-c C-w") #'deadgrep-edit-mode)))
 #+end_src
 
+** [[https://www.genivia.com/get-ugrep.html][Ugrep]]
+:PROPERTIES:
+:CUSTOM_ID: sec:ugrep
+:END:
+
+[[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 in those pages.
+
+#+caption[Use =ugrep= when available]:
+#+caption: Use =ugrep= when available.
+#+name: lst:use-ugrep
+#+begin_src emacs-lisp
+  (when (executable-find "ugrep")
+    (with-eval-after-load 'grep
+      (custom-set-variables
+       `(grep-template ,(string-join '("ugrep"
+                                       "--color=always"
+                                       "--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))))
+#+end_src
+
 * [[info:emacs#Version Control][Version Control (info)]]
 :PROPERTIES:
 :CUSTOM_ID: sec:version-control