@@ 146,7 146,7 @@ module Build = struct
     Sys.readdir dir
     |> Array.to_list
     |> List.map (Filename.concat dir)
-    |> List.filter Sys.is_regular_file
+    |> List.filter CCFun.(Sys.is_directory %> not)
     |> List.sort String.compare
 
   let compute_selector builds_conf =