diff --git a/nixos/modules/services/web-servers/apache-httpd/mediawiki.nix b/nixos/modules/services/web-servers/apache-httpd/mediawiki.nix
index 1ed489bcb095..405dc0307fac 100644
--- a/nixos/modules/services/web-servers/apache-httpd/mediawiki.nix
+++ b/nixos/modules/services/web-servers/apache-httpd/mediawiki.nix
@@ -91,12 +91,16 @@ let
     };
 
     skins = config.skins;
+    extensions = config.extensions;
 
     buildPhase =
       ''
         for skin in $skins; do
           cp -prvd $skin/* skins/
         done
+        for extension in $extensions; do
+          cp -prvd $extension/* extensions/
+        done
       ''; # */
 
     installPhase =
@@ -287,6 +291,16 @@ in
         '';
     };
 
+    extensions = mkOption {
+      default = [];
+      type = types.listOf types.path;
+      description =
+        ''
+          List of paths whose content is copied to the 'extensions'
+          subdirectory of the MediaWiki installation.
+        '';
+    };
+
     extraConfig = mkOption {
       type = types.lines;
       default = "";