diff --git a/otherlibs/dune-site/src/plugins/plugins.ml b/otherlibs/dune-site/src/plugins/plugins.ml
index 43580df6c5cf..ca2d2c7a4c6d 100644
--- a/otherlibs/dune-site/src/plugins/plugins.ml
+++ b/otherlibs/dune-site/src/plugins/plugins.ml
@@ -3,8 +3,10 @@ module Data = Dune_site_plugins_data
 
 let meta_fn = "META"
 
-let readdir dirs =
+let readdir =
   let ( / ) = Filename.concat in
+  fun dirs ->
+  
   List.concat
     (List.map
        (fun dir ->