diff --git a/modules/lang/data/config.el b/modules/lang/data/config.el
index 45ec4f6b1..24498563e 100644
--- a/modules/lang/data/config.el
+++ b/modules/lang/data/config.el
@@ -8,7 +8,9 @@
   (setq nxml-slash-auto-complete-flag t
         nxml-auto-insert-xml-declaration-flag t)
   (set-company-backend! 'nxml-mode '(company-nxml company-yasnippet))
-  (setq-hook! 'nxml-mode-hook tab-width nxml-child-indent))
+  (setq-hook! 'nxml-mode-hook tab-width nxml-child-indent)
+  (when (executable-find "xmllint")
+    (set-formatter! 'xmllint '("xmllint" "--format" "-") :modes '(nxml-mode))))
 
 
 ;;;###package csv-mode
diff --git a/modules/lang/data/doctor.el b/modules/lang/data/doctor.el
new file mode 100644
index 000000000..b18eb5d54
--- /dev/null
+++ b/modules/lang/data/doctor.el
@@ -0,0 +1,5 @@
+;;; lang/data/doctor.el -*- lexical-binding: t; -*-
+
+(when (modulep! :editor format)
+  (unless (executable-find "xmllint")
+    (warn! "Couldn't find xmllint. Formatting will be disabled.")))