diff --git a/engine/lib/dune b/engine/lib/dune
index 3c82e7e97..149ea13e6 100644
--- a/engine/lib/dune
+++ b/engine/lib/dune
@@ -54,8 +54,8 @@
   (with-stdout-to
    ast_visitors.ml
    (with-stdin-from
-        %{ast}
-        (run generate_visitors)))))
+    %{ast}
+    (run generate_visitors)))))
 
 (rule
  (target concrete_ident_generated.ml)
diff --git a/engine/utils/generate_visitors/errors.ml b/engine/utils/generate_visitors/errors.ml
index e44f68cd6..8288a8474 100644
--- a/engine/utils/generate_visitors/errors.ml
+++ b/engine/utils/generate_visitors/errors.ml
@@ -44,7 +44,6 @@ open struct
 end
 
 let yojson_of_t (e : t) = into_string e |> [%yojson_of: t_string]
-
 let _ = pp_t_string (* just to silence OCaml warning *)
 
 exception Error of t