diff --git a/doc/manual/generate-manpage.nix b/doc/manual/generate-manpage.nix
index 87891fa7a..41725aed6 100644
--- a/doc/manual/generate-manpage.nix
+++ b/doc/manual/generate-manpage.nix
@@ -1,8 +1,8 @@
 let
   inherit (builtins)
-    attrNames attrValues fromJSON listToAttrs mapAttrs
+    attrNames attrValues fromJSON listToAttrs mapAttrs groupBy
     concatStringsSep concatMap length lessThan replaceStrings sort;
-  inherit (import ./utils.nix) concatStrings optionalString filterAttrs trim squash unique showSettings;
+  inherit (import ./utils.nix) attrsToList concatStrings optionalString filterAttrs trim squash unique showSettings;
 in
 
 commandDump:
@@ -75,25 +75,27 @@ let
         (details ? doc)
         (replaceStrings ["@stores@"] [storeDocs] details.doc);
 
-      maybeOptions = optionalString (details.flags != {}) ''
+      maybeOptions = let
+        allVisibleOptions = filterAttrs
+          (_: o: ! o.hiddenCategory)
+          (details.flags // toplevel.flags);
+      in optionalString (allVisibleOptions != {}) ''
         # Options
 
-        ${showOptions details.flags toplevel.flags}
+        ${showOptions allVisibleOptions}
 
         > **Note**
         >
         > See [`man nix.conf`](@docroot@/command-ref/conf-file.md#command-line-flags) for overriding configuration settings with command line flags.
       '';
 
-      showOptions = options: commonOptions:
+      showOptions = allOptions:
         let
-          allOptions = options // commonOptions;
-          showCategory = cat: ''
-            ${optionalString (cat != "") "**${cat}:**"}
+          showCategory = cat: opts: ''
+            ${optionalString (cat != "") "## ${cat}"}
 
-            ${listOptions (filterAttrs (n: v: v.category == cat) allOptions)}
+            ${concatStringsSep "\n" (attrValues (mapAttrs showOption opts))}
             '';
-          listOptions = opts: concatStringsSep "\n" (attrValues (mapAttrs showOption opts));
           showOption = name: option:
             let
               shortName = optionalString
@@ -107,8 +109,13 @@ let
 
                 ${option.description}
             '';
-          categories = sort lessThan (unique (map (cmd: cmd.category) (attrValues allOptions)));
-        in concatStrings (map showCategory categories);
+          categories = mapAttrs
+            # Convert each group from a list of key-value pairs back to an attrset
+            (_: listToAttrs)
+            (groupBy
+              (cmd: cmd.value.category)
+              (attrsToList allOptions));
+        in concatStrings (attrValues (mapAttrs showCategory categories));
     in squash result;
 
   appendName = filename: name: (if filename == "nix" then "nix3" else filename) + "-" + name;
diff --git a/src/libutil/args.cc b/src/libutil/args.cc
index 8db293762..e410c7eec 100644
--- a/src/libutil/args.cc
+++ b/src/libutil/args.cc
@@ -236,7 +236,7 @@ nlohmann::json Args::toJSON()
 
     for (auto & [name, flag] : longFlags) {
         auto j = nlohmann::json::object();
-        if (hiddenCategories.count(flag->category)) continue;
+        j["hiddenCategory"] = hiddenCategories.count(flag->category) > 0;
         if (flag->aliases.count(name)) continue;
         if (flag->shortName)
             j["shortName"] = std::string(1, flag->shortName);