diff --git a/src/proto_alpha/lib_client/injection.ml b/src/proto_alpha/lib_client/injection.ml
index 56832cd849fa1179812e0e13b3ed99312eedd4b5..5006cd403a278676098f3b2fce2ced65b0885a10 100644
--- a/src/proto_alpha/lib_client/injection.ml
+++ b/src/proto_alpha/lib_client/injection.ml
@@ -393,6 +393,7 @@ let estimated_storage_single (type kind) ~tx_rollup_origination_size
         | Transfer_ticket_result {paid_storage_size_diff; _} ->
             Ok paid_storage_size_diff
         | Sc_rollup_originate_result {size; _} -> Ok size
+        | Zk_rollup_origination_result {storage_size; _} -> Ok storage_size
         | Transaction_result (Transaction_to_tx_rollup_result _) ->
             (* TODO: https://gitlab.com/tezos/tezos/-/issues/2339
                Storage fees for transaction rollup.
@@ -415,8 +416,7 @@ let estimated_storage_single (type kind) ~tx_rollup_origination_size
         | Sc_rollup_cement_result _ | Sc_rollup_publish_result _
         | Sc_rollup_refute_result _ | Sc_rollup_timeout_result _
         | Sc_rollup_recover_bond_result _
-        | Sc_rollup_dal_slot_subscribe_result _ | Zk_rollup_origination_result _
-          ->
+        | Sc_rollup_dal_slot_subscribe_result _ ->
             Ok Z.zero)
     | Skipped _ ->
         error_with "Cannot estimate storage of skipped operation"
diff --git a/src/proto_alpha/lib_client/operation_result.ml b/src/proto_alpha/lib_client/operation_result.ml
index 635c3da9afdb74a14c5405c708316ee7d4a67e81..b2d2c3fcf8997572c35c30f589a0648cae9d887c 100644
--- a/src/proto_alpha/lib_client/operation_result.ml
+++ b/src/proto_alpha/lib_client/operation_result.ml
@@ -791,8 +791,9 @@ let pp_manager_operation_contents_result ppf op_result =
   in
   let pp_zk_rollup_origination_result
       (Zk_rollup_origination_result
-        {consumed_gas; originated_zk_rollup; size = _; balance_updates}) =
+        {consumed_gas; originated_zk_rollup; storage_size; balance_updates}) =
     pp_consumed_gas ppf consumed_gas ;
+    pp_storage_size ppf storage_size ;
     Format.fprintf ppf "@,Address: %a" Zk_rollup.Address.pp originated_zk_rollup ;
     pp_balance_updates ppf balance_updates
   in
diff --git a/src/proto_alpha/lib_protocol/apply.ml b/src/proto_alpha/lib_protocol/apply.ml
index 3374e097ab2e68e8288d224a3e58e55c9998ffbb..f82c5a2095f8d5552c686c8566990da7cdda68c2 100644
--- a/src/proto_alpha/lib_protocol/apply.ml
+++ b/src/proto_alpha/lib_protocol/apply.ml
@@ -1612,7 +1612,7 @@ let burn_manager_storage_fees :
         ctxt
         ~storage_limit
         ~payer
-        payload.size
+        payload.storage_size
       >>=? fun (ctxt, storage_limit, balance_updates) ->
       let result =
         Zk_rollup_origination_result {payload with balance_updates}
diff --git a/src/proto_alpha/lib_protocol/apply_results.ml b/src/proto_alpha/lib_protocol/apply_results.ml
index a7c62eba5632943fc5521283e3ec6037bcf1e270..91e72b60892985baecf5c90608baa350bacc6e83 100644
--- a/src/proto_alpha/lib_protocol/apply_results.ml
+++ b/src/proto_alpha/lib_protocol/apply_results.ml
@@ -180,7 +180,7 @@ type _ successful_manager_operation_result =
       balance_updates : Receipt.balance_updates;
       originated_zk_rollup : Zk_rollup.t;
       consumed_gas : Gas.Arith.fp;
-      size : Z.t;
+      storage_size : Z.t;
     }
       -> Kind.zk_rollup_origination successful_manager_operation_result
 
@@ -753,10 +753,9 @@ module Manager_result = struct
       ~op_case:Operation.Encoding.Manager_operations.zk_rollup_origination_case
       ~encoding:
         Data_encoding.(
-          obj5
+          obj4
             (req "balance_updates" Receipt.balance_updates_encoding)
             (req "originated_zk_rollup" Zk_rollup.Address.encoding)
-            (dft "consumed_gas" Gas.Arith.n_integral_encoding Gas.Arith.zero)
             (dft "consumed_milligas" Gas.Arith.n_fp_encoding Gas.Arith.zero)
             (req "size" z))
       ~select:(function
@@ -766,26 +765,13 @@ module Manager_result = struct
       ~kind:Kind.Zk_rollup_origination_manager_kind
       ~proj:(function
         | Zk_rollup_origination_result
-            {balance_updates; originated_zk_rollup; consumed_gas; size} ->
-            ( balance_updates,
-              originated_zk_rollup,
-              Gas.Arith.ceil consumed_gas,
-              consumed_gas,
-              size ))
+            {balance_updates; originated_zk_rollup; consumed_gas; storage_size}
+          ->
+            (balance_updates, originated_zk_rollup, consumed_gas, storage_size))
       ~inj:
-        (fun ( balance_updates,
-               originated_zk_rollup,
-               consumed_gas,
-               consumed_milligas,
-               size ) ->
-        assert (Gas.Arith.(equal (ceil consumed_milligas) consumed_gas)) ;
+        (fun (balance_updates, originated_zk_rollup, consumed_gas, storage_size) ->
         Zk_rollup_origination_result
-          {
-            balance_updates;
-            originated_zk_rollup;
-            consumed_gas = consumed_milligas;
-            size;
-          })
+          {balance_updates; originated_zk_rollup; consumed_gas; storage_size})
 
   let sc_rollup_originate_case =
     make
diff --git a/src/proto_alpha/lib_protocol/apply_results.mli b/src/proto_alpha/lib_protocol/apply_results.mli
index 9b70c8eb0166c6ac877c6bb86072a2b9813e838f..6b3903dd929f2bed265f76c57f9a524fadf5460e 100644
--- a/src/proto_alpha/lib_protocol/apply_results.mli
+++ b/src/proto_alpha/lib_protocol/apply_results.mli
@@ -276,7 +276,9 @@ and _ successful_manager_operation_result =
       balance_updates : Receipt.balance_updates;
       originated_zk_rollup : Zk_rollup.t;
       consumed_gas : Gas.Arith.fp;
-      size : Z.t;
+      (* Number of bytes allocated by the ZKRU origination.
+         Used to burn storage fees. *)
+      storage_size : Z.t;
     }
       -> Kind.zk_rollup_origination successful_manager_operation_result
 
diff --git a/src/proto_alpha/lib_protocol/operation_repr.ml b/src/proto_alpha/lib_protocol/operation_repr.ml
index 614f47a44e2900dd754ca2ef3eb0cdf7c949b12e..9a33dffa69ab06ab4468eae9e35a116b54d674f4 100644
--- a/src/proto_alpha/lib_protocol/operation_repr.ml
+++ b/src/proto_alpha/lib_protocol/operation_repr.ml
@@ -1030,26 +1030,9 @@ module Encoding = struct
           encoding =
             obj4
               (req "public_parameters" Plonk.public_parameters_encoding)
-              (let circuits_info_encoding =
-                 conv_with_guard
-                   (fun m ->
-                     List.of_seq @@ Zk_rollup_account_repr.SMap.to_seq m)
-                   (fun l ->
-                     let m =
-                       Zk_rollup_account_repr.SMap.of_seq @@ List.to_seq l
-                     in
-                     if
-                       (* Check that the list has no duplicated keys *)
-                       Compare.List_length_with.(
-                         l <> Zk_rollup_account_repr.SMap.cardinal m)
-                     then
-                       Error
-                         "Zk_rollup_origination: circuits_info has duplicated \
-                          keys"
-                     else Ok m)
-                   (list (tup2 string bool))
-               in
-               req "circuits_info" circuits_info_encoding)
+              (req
+                 "circuits_info"
+                 Zk_rollup_account_repr.circuits_info_encoding)
               (req "init_state" Zk_rollup_state_repr.encoding)
               (* TODO https://gitlab.com/tezos/tezos/-/issues/3655
                  Encoding of non-negative [nb_ops] for origination *)
diff --git a/src/proto_alpha/lib_protocol/storage.mli b/src/proto_alpha/lib_protocol/storage.mli
index 590988c668affbd38dc07404887646508c63959b..ebbf7d61d134eabf6479ec4f35cdbd9a7803007a 100644
--- a/src/proto_alpha/lib_protocol/storage.mli
+++ b/src/proto_alpha/lib_protocol/storage.mli
@@ -877,7 +877,7 @@ module Dal : sig
 end
 
 module Zk_rollup : sig
-  (** Zero ZK rollup.
+  (** ZK rollup.
 
       Each ZK rollup is associated to:
 
diff --git a/src/proto_alpha/lib_protocol/test/helpers/dummy_zk_rollup.ml b/src/proto_alpha/lib_protocol/test/helpers/dummy_zk_rollup.ml
index b961f894b1286121212e2104d85416f1e302d7f3..cb976864a1c7824480b434826710c37226caea2d 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/dummy_zk_rollup.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/dummy_zk_rollup.ml
@@ -1,6 +1,6 @@
 (*****************************************************************************)
 (*                                                                           *)
-(* MIT License                                                               *)
+(* Open Source License                                                       *)
 (* Copyright (c) 2022 Nomadic Labs <contact@nomadic-labs.com>                *)
 (*                                                                           *)
 (* Permission is hereby granted, free of charge, to any person obtaining a   *)
@@ -77,30 +77,32 @@ type op_code
 module Bound : sig
   type 'a t = private Z.t
 
-  val max_balance : balance t
+  val bound_balance : balance t
 
-  val max_amount : amount t
+  val bound_amount : amount t
 
-  val max_fee : fee t
+  val bound_fee : fee t
 
-  val max_op_code : op_code t
+  val bound_op_code : op_code t
 
   val v : 'a t -> Z.t
 end = struct
   type 'a t = Z.t
 
-  (** Maximum ticket balance, as found in the price field of an operation's
-      header *)
-  let max_balance = Z.(shift_left one 20)
+  (** These bounds are exclusive. *)
 
-  (** Maximum ticket amount, used for fee circuit *)
-  let max_amount = Z.(shift_left one 20)
+  (** Upper bound for ticket balance, as found in the price field of an
+      operation's header *)
+  let bound_balance = Z.(shift_left one 20)
 
-  (** Maximum fee amount for one public operation *)
-  let max_fee = Z.(shift_left one 10)
+  (** Upper bound for ticket amount, used for fee circuit *)
+  let bound_amount = Z.(shift_left one 20)
 
-  (** Maximum value for op code *)
-  let max_op_code = Z.(shift_left one 1)
+  (** Upper bound for fee amount of one public operation *)
+  let bound_fee = Z.(shift_left one 10)
+
+  (** Upper bound for op code *)
+  let bound_op_code = Z.one
 
   let v x = x
 end
@@ -138,9 +140,9 @@ module Types = struct
     (** Dummy values for these types. Useful to get the circuit without having
         the actual inputs. *)
     module Dummy = struct
-      let op_code = Bounded.make ~bound:Bound.max_op_code Z.zero
+      let op_code = Bounded.make ~bound:Bound.bound_op_code Z.zero
 
-      let balance = Bounded.make ~bound:Bound.max_balance Z.zero
+      let balance = Bounded.make ~bound:Bound.bound_balance Z.zero
 
       let tezos_pkh = Environment.Signature.Public_key_hash.zero
 
@@ -182,7 +184,8 @@ module Types = struct
 
     open Encodings (L)
 
-    let op_code_encoding ~safety = Bounded_e.encoding ~safety Bound.max_op_code
+    let op_code_encoding ~safety =
+      Bounded_e.encoding ~safety Bound.bound_op_code
 
     let encoding_to_scalar e x =
       let bs = Data_encoding.Binary.to_bytes_exn e x in
@@ -202,9 +205,9 @@ module Types = struct
         (encoding_of_scalar Signature.Public_key_hash.encoding)
         scalar_encoding
 
-    let amount_encoding ~safety = Bounded_e.encoding ~safety Bound.max_amount
+    let amount_encoding ~safety = Bounded_e.encoding ~safety Bound.bound_amount
 
-    let fee_encoding ~safety = Bounded_e.encoding ~safety Bound.max_fee
+    let fee_encoding ~safety = Bounded_e.encoding ~safety Bound.bound_fee
 
     let ticket_encoding ~safety (bound : 'a Bound.t) :
         ('a ticket, 'a ticket_u, _) encoding =
@@ -216,7 +219,7 @@ module Types = struct
         (obj2_encoding scalar_encoding (Bounded_e.encoding ~safety bound))
 
     let ticket_balance_encoding ~safety =
-      ticket_encoding ~safety Bound.max_balance
+      ticket_encoding ~safety Bound.bound_balance
 
     let header_encoding ~safety : (header, header_u, _) encoding =
       conv
@@ -361,8 +364,7 @@ end = struct
     (* zkr1PxS4vgvBsf6XVHRSB7UJKcrTWee8Dp7Wx *)
     Hex.to_bytes_exn (`Hex "c9a524d4db6514471775c380231afc10f2ef6ba3")
 
-  let dummy_ticket_hash =
-    Hex.to_bytes_exn (`Hex (String.init (2 * 32) @@ Fun.const '0'))
+  let dummy_ticket_hash = Bytes.make 32 '0'
 
   let _of_proto_state : Zk_rollup.State.t -> Types.P.state =
    fun s -> Bls12_381.Fr.is_one s.(0)
@@ -392,7 +394,7 @@ end = struct
              VC.predicate_op
                ~old_state:false
                ~new_state:true
-               ~fee:(T.Bounded.make ~bound:Bound.max_fee Z.zero)
+               ~fee:(T.Bounded.make ~bound:Bound.bound_fee Z.zero)
                ~exit_validity:false
                ~rollup_id:Dummy.tezos_pkh
                dummy_op );
@@ -400,14 +402,14 @@ end = struct
              VC.predicate_batch
                ~old_state:false
                ~new_state:true
-               ~fees:(T.Bounded.make ~bound:Bound.max_amount Z.zero)
+               ~fees:(T.Bounded.make ~bound:Bound.bound_amount Z.zero)
                ~rollup_id:Dummy.tezos_pkh
                (Stdlib.List.init Params.batch_size (Fun.const dummy_op)) );
            ( "fee",
              VC.predicate_fees
                ~old_state:false
                ~new_state:false
-               ~fees:(T.Bounded.make ~bound:Bound.max_amount Z.zero) );
+               ~fees:(T.Bounded.make ~bound:Bound.bound_amount Z.zero) );
          ]
 
   let circuits =
diff --git a/src/proto_alpha/lib_protocol/test/helpers/zk_rollup_l2_helpers.ml b/src/proto_alpha/lib_protocol/test/helpers/zk_rollup_l2_helpers.ml
index af6814716a1501b332455134b9dad51c64f05550..eb710552b7cc8a4d493180c80f1b3c9db9df6221 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/zk_rollup_l2_helpers.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/zk_rollup_l2_helpers.ml
@@ -1 +1,26 @@
+(*****************************************************************************)
+(*                                                                           *)
+(* Open Source License                                                       *)
+(* Copyright (c) 2022 Nomadic Labs <contact@nomadic-labs.com>                *)
+(*                                                                           *)
+(* Permission is hereby granted, free of charge, to any person obtaining a   *)
+(* copy of this software and associated documentation files (the "Software"),*)
+(* to deal in the Software without restriction, including without limitation *)
+(* the rights to use, copy, modify, merge, publish, distribute, sublicense,  *)
+(* and/or sell copies of the Software, and to permit persons to whom the     *)
+(* Software is furnished to do so, subject to the following conditions:      *)
+(*                                                                           *)
+(* The above copyright notice and this permission notice shall be included   *)
+(* in all copies or substantial portions of the Software.                    *)
+(*                                                                           *)
+(* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR*)
+(* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,  *)
+(* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL   *)
+(* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER*)
+(* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING   *)
+(* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER       *)
+(* DEALINGS IN THE SOFTWARE.                                                 *)
+(*                                                                           *)
+(*****************************************************************************)
+
 module Dummy_zk_rollup = Dummy_zk_rollup
diff --git a/src/proto_alpha/lib_protocol/zk_rollup_account_repr.ml b/src/proto_alpha/lib_protocol/zk_rollup_account_repr.ml
index 06ed67a39712aa4a84bdc4fb71abda18a9a763ed..d9a6b421bb5ee30c957dc3901a64f3e6fdda5b57 100644
--- a/src/proto_alpha/lib_protocol/zk_rollup_account_repr.ml
+++ b/src/proto_alpha/lib_protocol/zk_rollup_account_repr.ml
@@ -36,12 +36,25 @@ type dynamic = {state : Zk_rollup_state_repr.t}
 
 type t = {static : static; dynamic : dynamic}
 
+let circuits_info_encoding : bool SMap.t Data_encoding.t =
+  let open Data_encoding in
+  conv_with_guard
+    (fun m -> List.of_seq @@ SMap.to_seq m)
+    (fun l ->
+      let m = SMap.of_seq @@ List.to_seq l in
+      if
+        (* Check that the list has no duplicated keys *)
+        Compare.List_length_with.(l <> SMap.cardinal m)
+      then Error "Zk_rollup_origination: circuits_info has duplicated keys"
+      else Ok m)
+    (list (tup2 string bool))
+
 let encoding =
   let open Data_encoding in
   let static_encoding =
     let circuits_info_encoding =
       conv
-        (fun m -> List.of_seq @@ SMap.to_seq m)
+        SMap.bindings
         (fun l -> SMap.of_seq @@ List.to_seq l)
         (list (tup2 string bool))
     in
diff --git a/src/proto_alpha/lib_protocol/zk_rollup_account_repr.mli b/src/proto_alpha/lib_protocol/zk_rollup_account_repr.mli
index 37b4eae02b04d32b68c00e4be377507f6ea1272d..c84c94746dd2ceeafbd23d646e7d20d92dbfc080 100644
--- a/src/proto_alpha/lib_protocol/zk_rollup_account_repr.mli
+++ b/src/proto_alpha/lib_protocol/zk_rollup_account_repr.mli
@@ -50,3 +50,7 @@ type dynamic = {
 type t = {static : static; dynamic : dynamic}
 
 val encoding : t Data_encoding.t
+
+(* Encoding for the [circuits_info] field.
+   Checks that keys are not duplicated in serialized representation. *)
+val circuits_info_encoding : bool SMap.t Data_encoding.t
diff --git a/src/proto_alpha/lib_protocol/zk_rollup_apply.ml b/src/proto_alpha/lib_protocol/zk_rollup_apply.ml
index df361b65d1ba11f4d167f050403bbb9e5ffdb981..2d6704f98221a94229130774d14fb3142bb34c28 100644
--- a/src/proto_alpha/lib_protocol/zk_rollup_apply.ml
+++ b/src/proto_alpha/lib_protocol/zk_rollup_apply.ml
@@ -50,22 +50,24 @@ let () =
     (fun () -> Zk_rollup_negative_nb_ops)
 
 let assert_feature_enabled ctxt =
-  fail_unless (Constants.zk_rollup_enable ctxt) Zk_rollup_feature_disabled
+  error_unless (Constants.zk_rollup_enable ctxt) Zk_rollup_feature_disabled
 
 let originate ~ctxt_before_op ~ctxt ~public_parameters ~circuits_info
     ~init_state ~nb_ops =
-  assert_feature_enabled ctxt >>=? fun () ->
-  fail_when Compare.Int.(nb_ops < 0) Zk_rollup_negative_nb_ops >>=? fun () ->
-  Zk_rollup.originate
-    ctxt
-    {
-      public_parameters;
-      state_length = Array.length init_state;
-      circuits_info;
-      nb_ops;
-    }
-    ~init_state
-  >>=? fun (ctxt, originated_zk_rollup, size) ->
+  let open Lwt_result_syntax in
+  let*? () = assert_feature_enabled ctxt in
+  let*? () = error_when Compare.Int.(nb_ops < 0) Zk_rollup_negative_nb_ops in
+  let+ ctxt, originated_zk_rollup, storage_size =
+    Zk_rollup.originate
+      ctxt
+      {
+        public_parameters;
+        state_length = Array.length init_state;
+        circuits_info;
+        nb_ops;
+      }
+      ~init_state
+  in
   let consumed_gas = Gas.consumed ~since:ctxt_before_op ~until:ctxt in
   let result =
     Apply_results.Zk_rollup_origination_result
@@ -75,7 +77,7 @@ let originate ~ctxt_before_op ~ctxt ~public_parameters ~circuits_info
         (* TODO https://gitlab.com/tezos/tezos/-/issues/3544
            Carbonate ZKRU operations *)
         consumed_gas;
-        size;
+        storage_size;
       }
   in
-  return (ctxt, result, [])
+  (ctxt, result, [])
diff --git a/src/proto_alpha/lib_protocol/zk_rollup_apply.mli b/src/proto_alpha/lib_protocol/zk_rollup_apply.mli
index c54761db5e9178d85a2168f97a85f6d19cdaf302..0fd88b7de2b8a6720718730ccea15dc1c6d050df 100644
--- a/src/proto_alpha/lib_protocol/zk_rollup_apply.mli
+++ b/src/proto_alpha/lib_protocol/zk_rollup_apply.mli
@@ -48,7 +48,7 @@ type error +=
         activated.}
     }
 *)
-val assert_feature_enabled : t -> unit tzresult Lwt.t
+val assert_feature_enabled : t -> unit tzresult
 
 (** [originate ~ctxt_before_op ~ctxt ~public_parameters ~transcript
                ~circuits_info ~init_state ~nb_ops]
diff --git a/src/proto_alpha/lib_protocol/zk_rollup_operation_repr.ml b/src/proto_alpha/lib_protocol/zk_rollup_operation_repr.ml
index f020df556484fedcafaeafd16ed02af05ad0d240..66f4c227c4c9367c1a094398a242e00a94e21b20 100644
--- a/src/proto_alpha/lib_protocol/zk_rollup_operation_repr.ml
+++ b/src/proto_alpha/lib_protocol/zk_rollup_operation_repr.ml
@@ -34,12 +34,12 @@ type t = {
 let int_to_scalar x = Zk_rollup_scalar.of_z (Z.of_int x)
 
 let pkh_to_scalar x =
-  Zk_rollup_scalar.of_bytes
-    (Data_encoding.Binary.to_bytes_exn Signature.Public_key_hash.encoding x)
+  Zk_rollup_scalar.of_bits
+    (Data_encoding.Binary.to_string_exn Signature.Public_key_hash.encoding x)
 
 let ticket_hash_to_scalar ticket_hash =
-  Zk_rollup_scalar.of_bytes
-  @@ Data_encoding.Binary.to_bytes_exn Ticket_hash_repr.encoding ticket_hash
+  Zk_rollup_scalar.of_bits
+  @@ Data_encoding.Binary.to_string_exn Ticket_hash_repr.encoding ticket_hash
 
 let to_scalar_array {op_code; price; l1_dst; rollup_id; payload} =
   Array.concat
diff --git a/src/proto_alpha/lib_protocol/zk_rollup_repr.ml b/src/proto_alpha/lib_protocol/zk_rollup_repr.ml
index 35497192cc9a4cfb8733d9b4120008f135270295..f52bda0a2718f01152c25acc443fced9e75b6db4 100644
--- a/src/proto_alpha/lib_protocol/zk_rollup_repr.ml
+++ b/src/proto_alpha/lib_protocol/zk_rollup_repr.ml
@@ -76,8 +76,8 @@ end
 type t = Address.t
 
 let to_scalar x =
-  Zk_rollup_scalar.of_bytes
-    (Data_encoding.Binary.to_bytes_exn Address.encoding x)
+  Zk_rollup_scalar.of_bits
+    (Data_encoding.Binary.to_string_exn Address.encoding x)
 
 type pending_list =
   | Empty of {next_index : int64}
diff --git a/src/proto_alpha/lib_protocol/zk_rollup_scalar.ml b/src/proto_alpha/lib_protocol/zk_rollup_scalar.ml
index 1bdc3d01a05e6e9f8e121bf32085fba4d99dc604..8db6c7b68c1c333fc2c688a98fd35cd1fdac0292 100644
--- a/src/proto_alpha/lib_protocol/zk_rollup_scalar.ml
+++ b/src/proto_alpha/lib_protocol/zk_rollup_scalar.ml
@@ -31,7 +31,7 @@ let of_z z =
      t a field element *)
   Bls12_381.Fr.of_z z
 
-let of_bytes bs =
-  (* The bytes are interpreted as a Z integer *)
-  let z = Z.of_bits @@ Bytes.to_string bs in
+let of_bits bs =
+  (* The bits are interpreted as a Z integer *)
+  let z = Z.of_bits bs in
   of_z z
diff --git a/src/proto_alpha/lib_protocol/zk_rollup_scalar.mli b/src/proto_alpha/lib_protocol/zk_rollup_scalar.mli
index 2cfce7d9ee2f1fe733be15b30ba1a6bc025f0305..0b9307cefe3ff708cda473503f1bb6ca33d992e5 100644
--- a/src/proto_alpha/lib_protocol/zk_rollup_scalar.mli
+++ b/src/proto_alpha/lib_protocol/zk_rollup_scalar.mli
@@ -34,7 +34,7 @@ type t = Bls12_381.Fr.t
     is applied. *)
 val of_z : Z.t -> t
 
-(** Safe conversion from bytes.
+(** Safe conversion from bits, represented as a string.
     If the numerical value is not in the field, modulo reduction
     is applied. *)
-val of_bytes : bytes -> t
+val of_bits : string -> t