diff --git a/src/stdune/sexp.ml b/src/stdune/sexp.ml
index 6ea5468f..f30bbe52 100644
--- a/src/stdune/sexp.ml
+++ b/src/stdune/sexp.ml
@@ -185,7 +185,7 @@ module Of_sexp = struct
   let string_set sexp = String.Set.of_list (list string sexp)
   let string_map f sexp =
     match String.Map.of_list (list (pair string f) sexp) with
-    | Ok x -> x
+    | Result.Ok x -> x
     | Error (key, _v1, _v2) ->
       of_sexp_error sexp (Printf.sprintf "key %S present multiple times" key)
 
@@ -250,7 +250,7 @@ module Of_sexp = struct
   let map_validate parse ~f state =
     let x, state' = parse state in
     match f x with
-    | Ok x -> x, state'
+    | Result.Ok x -> x, state'
     | Error msg ->
       let parsed =
         Name_map.merge state.unparsed state'.unparsed ~f:(fun _key before after ->
diff --git a/src/stdune/sexp.mli b/src/stdune/sexp.mli
index 29dace12..b4cb16fb 100644
--- a/src/stdune/sexp.mli
+++ b/src/stdune/sexp.mli
@@ -109,7 +109,10 @@ module Of_sexp : sig
     -> 'a option record_parser
   val field_b : string -> bool record_parser
 
-  val map_validate : 'a record_parser -> f:('a -> ('b, string) result) -> 'b record_parser
+  val map_validate
+    :  'a record_parser
+    -> f:('a -> ('b, string) Result.result)
+    -> 'b record_parser
 
   val ignore_fields : string list -> unit record_parser