diff --git a/pkgs/servers/sql/postgresql/generic.nix b/pkgs/servers/sql/postgresql/generic.nix
index 10cf487ad4a31..863ebb108e5c8 100644
--- a/pkgs/servers/sql/postgresql/generic.nix
+++ b/pkgs/servers/sql/postgresql/generic.nix
@@ -307,6 +307,7 @@ let
       postInstall =
         ''
           moveToOutput "bin/ecpg" "$dev"
+          # The following seems to fail without this comment (?)
           moveToOutput "lib/pgxs" "$dev"
 
           # Pretend pg_config is located in $out/bin to return correct paths, but