diff --git a/_oasis b/_oasis
index 249d3059d..2f8bfc78b 100644
--- a/_oasis
+++ b/_oasis
@@ -2,7 +2,7 @@ OASISFormat:           0.4
 OCamlVersion:          >= 4.03.0
 FindlibVersion:        >= 1.3.2
 Name:                  ppx_let
-Version:               114.03+54
+Version:               114.04+40
 Synopsis:              Monadic let-bindings
 Authors:               Jane Street Group, LLC <opensource@janestreet.com>
 Copyrights:            (C) 2015-2016 Jane Street Group LLC <opensource@janestreet.com>
diff --git a/src/ppx_let.ml b/src/ppx_let.ml
index ce38f4e08..7c5c3198c 100644
--- a/src/ppx_let.ml
+++ b/src/ppx_let.ml
@@ -56,14 +56,9 @@ let expand_with_tmp_vars ~loc bindings expr ~f =
 ;;
 
 let bind_apply ~loc extension_name ~arg ~fn =
-  let fn_label =
-    match (extension_name : Extension_name.t) with
-    | Bind | Bind_open -> ""
-    | Map  | Map_open  -> "f"
-  in
   pexp_apply ~loc
     (eoperator ~loc (Extension_name.operator_name extension_name))
-    [(Nolabel, arg); (Labelled fn_label, fn)]
+    [(Nolabel, arg); (Labelled "f", fn)]
 ;;
 
 let maybe_open extension_name ~to_open:module_to_open expr =
diff --git a/test/test.ml b/test/test.ml
index 0dc4960fe..90de6a874 100644
--- a/test/test.ml
+++ b/test/test.ml
@@ -6,7 +6,7 @@ module Monad_example = struct
       val return : 'a -> 'a t
       module Let_syntax : sig
         val return : 'a -> 'a t
-        val bind   : 'a t -> ('a -> 'b t) -> 'b t
+        val bind   : 'a t -> f:('a -> 'b t) -> 'b t
         val map    : 'a t -> f:('a -> 'b) -> 'b t
         val both   : 'a t -> 'b t -> ('a * 'b) t
         module Open_on_rhs  : sig val return : 'a -> 'a t end
@@ -15,7 +15,7 @@ module Monad_example = struct
   end = struct
     type 'a t = 'a
     let return x = x
-    let bind x f = f x
+    let bind x ~f = f x
     let map x ~f = f x
     let both x y = (x, y)
     module Let_syntax = struct