diff --git a/CHANGES.md b/CHANGES.md
index ebcab2b..3bae4b4 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,7 @@
+## v0.14.1
+
+- Depend on ppxlib >= v0.15.0.
+
 ## v0.11
 
 - Depend on ppxlib instead of (now deprecated) ppx\_core, ppx\_driver and
diff --git a/expander/str_generate_sexp_grammar.ml b/expander/str_generate_sexp_grammar.ml
index 90e8690..5029ac0 100644
--- a/expander/str_generate_sexp_grammar.ml
+++ b/expander/str_generate_sexp_grammar.ml
@@ -5,6 +5,11 @@ open! Sexp.Private.Raw_grammar
 module Var_name  = String
 module Type_name = String
 
+module Longident = struct
+  include Longident
+  include (val Comparator.make ~compare ~sexp_of_t)
+end
+
 let debug_s message values =
   Caml.prerr_endline (Sexp.to_string_hum (Sexp.message message values))
 ;;
@@ -214,8 +219,7 @@ end = struct
   let create rec_flag tds : t =
     Init
       { explicit =
-          List.map tds ~f:(fun td ->
-            td.ptype_name.txt, Explicit_type_variables.create td)
+          List.map tds ~f:(fun td -> td.ptype_name.txt, Explicit_type_variables.create td)
           |> Map.of_alist_exn (module Type_name)
       ; implicit = Map.empty (module Longident)
       ; rec_flag
@@ -413,8 +417,7 @@ let type_of_core_type env0 type_name ctype =
   let rec type_of_core_type env ctype =
     match Opaque.create ctype with
     | Opaque -> unsupported_builtin ~loc:ctype.ptyp_loc "opaque"
-    | Not_opaque { ptyp_desc; ptyp_loc = loc; ptyp_attributes = _; ptyp_loc_stack = _ }
-      ->
+    | Not_opaque { ptyp_desc; ptyp_loc = loc; ptyp_attributes = _; ptyp_loc_stack = _ } ->
       (match ptyp_desc with
        | Ptyp_any              ->
          (* For consistency with [%of_sexp: _] which treats [_] as unsatisfiable. *)
@@ -423,8 +426,7 @@ let type_of_core_type env0 type_name ctype =
        | Ptyp_arrow (_, _, _)  -> unsupported_builtin ~loc "fun"
        | Ptyp_tuple core_types ->
          List
-           (List.map core_types ~f:(fun core_type ->
-              One (type_of_core_type env core_type)))
+           (List.map core_types ~f:(fun core_type -> One (type_of_core_type env core_type)))
        | Ptyp_constr (ident, args) ->
          type_of_type_constructor
            ~loc
@@ -470,9 +472,7 @@ let record_type_of_label_declarations env type_name lds ~allow_extra_fields =
   { allow_extra_fields
   ; fields =
       List.map lds ~f:(fun ld ->
-        let { pld_name; pld_mutable = _; pld_type; pld_loc; pld_attributes = _ } =
-          ld
-        in
+        let { pld_name; pld_mutable = _; pld_type; pld_loc; pld_attributes = _ } = ld in
         let field =
           match Attrs.Record_field_handler.Of_sexp.create ~loc:pld_loc ld with
           | None ->
@@ -593,8 +593,8 @@ let collect_type_variables_of_polymorphic_grammar core_type =
   | { ptyp_desc = Ptyp_object _; _ } ->
     not_supported
       ~loc:core_type.ptyp_loc
-      "objects, except the syntax [%sexp_grammar: < for_all : 'a 'b . ... >] to \
-       generate grammars of polymorphic types"
+      "objects, except the syntax [%sexp_grammar: < for_all : 'a 'b . ... >] to generate \
+       grammars of polymorphic types"
   | _ -> [], core_type
 ;;
 
@@ -721,8 +721,7 @@ let to_pat_and_expr { grammars; generic_group; group; loc; module_path } =
         =
         [%e generic_group]
       in
-      let ([%p Pattern.the_group ~loc]
-           : Ppx_sexp_conv_lib.Sexp.Private.Raw_grammar.group)
+      let ([%p Pattern.the_group ~loc] : Ppx_sexp_conv_lib.Sexp.Private.Raw_grammar.group)
         =
         [%e group]
       in
diff --git a/test/expect/regular_vs_polymorphic_variants.diff b/test/expect/regular_vs_polymorphic_variants.diff
index 312b295..b2b613e 100644
--- a/test/expect/regular_vs_polymorphic_variants.diff
+++ b/test/expect/regular_vs_polymorphic_variants.diff
@@ -10,8 +10,10 @@
 -|      ; ggid          = "\239\242\007o\016\222\178\133\218\153\146w\129\255\167\208"
 +|      ; ggid          = "\133a\241\019; \198\184U\181\220#\191\190\200\b"
 @|============================================================
--|                , Variant { ignore_capitalization = true; alts = [ "A", []; "B", [] ] }
+-|                , Variant { ignore_capitalization = true; alts = [ "A", []; "B", [] ] } )
+-|            )
 +|                , Variant { ignore_capitalization = false; alts = [ "A", []; "B", [] ] }
++|                ) )
 @|============================================================
 -|      ; origin         = "test_regular_variants.ml.Nullary"
 +|      ; origin         = "test_polymorphic_variants.ml.Nullary"
@@ -56,8 +58,8 @@
 -|      | Sexp_list     of int sexp_list [@warning "-3"]
 +|      [ `Int           of int
 +|      | `List          of int list
-+|      | `Sexp_dot_list of int list[@sexp.list]
-+|      | `Sexp_list     of int sexp_list[@warning "-3"]
++|      | `Sexp_dot_list of int list [@sexp.list]
++|      | `Sexp_list     of int sexp_list [@warning "-3"]
 +|      ]
 @|============================================================
 -|  type t = With_sexp.t =
@@ -68,8 +70,8 @@
 +|  type t =
 +|    [ `Int           of int
 +|    | `List          of int list
-+|    | `Sexp_dot_list of int list[@sexp.list]
-+|    | `Sexp_list     of int sexp_list[@warning "-3"]
++|    | `Sexp_dot_list of int list [@sexp.list]
++|    | `Sexp_list     of int sexp_list [@warning "-3"]
 +|    ]
 @|============================================================
 -|      ; ggid          = "\219\014J\247\148Iq\193\248\rk\216J\012\200\152"
diff --git a/test/expect/test_polymorphic_record_fields.ml b/test/expect/test_polymorphic_record_fields.ml
index 2124da8..f8191dd 100644
--- a/test/expect/test_polymorphic_record_fields.ml
+++ b/test/expect/test_polymorphic_record_fields.ml
@@ -140,8 +140,7 @@ module Inline_record = struct
                           , [ Fields
                                 { allow_extra_fields = false
                                 ; fields             =
-                                    [ ( "a"
-                                      , { optional = false; args = [ One (Union []) ] } )
+                                    [ "a", { optional = false; args = [ One (Union []) ] }
                                     ]
                                 }
                             ] )
diff --git a/test/expect/test_polymorphic_variants.ml b/test/expect/test_polymorphic_variants.ml
index deb260c..21db3b5 100644
--- a/test/expect/test_polymorphic_variants.ml
+++ b/test/expect/test_polymorphic_variants.ml
@@ -108,8 +108,8 @@ module Sexp_list = struct
     type t =
       [ `Int           of int
       | `List          of int list
-      | `Sexp_dot_list of int list[@sexp.list]
-      | `Sexp_list     of int sexp_list[@warning "-3"]
+      | `Sexp_dot_list of int list [@sexp.list]
+      | `Sexp_list     of int sexp_list [@warning "-3"]
       ]
     [@@deriving sexp]
   end
@@ -117,8 +117,8 @@ module Sexp_list = struct
   type t =
     [ `Int           of int
     | `List          of int list
-    | `Sexp_dot_list of int list[@sexp.list]
-    | `Sexp_list     of int sexp_list[@warning "-3"]
+    | `Sexp_dot_list of int list [@sexp.list]
+    | `Sexp_list     of int sexp_list [@warning "-3"]
     ]
   [@@deriving_inline sexp_grammar]
 
diff --git a/test/expect/test_recursive_groups.ml b/test/expect/test_recursive_groups.ml
index 8300a41..a4a02f5 100644
--- a/test/expect/test_recursive_groups.ml
+++ b/test/expect/test_recursive_groups.ml
@@ -14,9 +14,8 @@ module One_type = struct
       ; types         =
           [ ( "t"
             , Variant
-                { ignore_capitalization = true
-                ; alts                  = [ "T", [ One (Implicit_var 0) ] ]
-                } )
+                { ignore_capitalization = true; alts = [ "T", [ One (Implicit_var 0) ] ] }
+            )
           ]
       }
     in
diff --git a/test/expect/test_regular_variants.ml b/test/expect/test_regular_variants.ml
index e646931..790e376 100644
--- a/test/expect/test_regular_variants.ml
+++ b/test/expect/test_regular_variants.ml
@@ -18,8 +18,8 @@ module Nullary = struct
           [ ( "t"
             , Explicit_bind
                 ( [ "a" ]
-                , Variant { ignore_capitalization = true; alts = [ "A", []; "B", [] ] }
-                ) )
+                , Variant { ignore_capitalization = true; alts = [ "A", []; "B", [] ] } )
+            )
           ]
       }
     in