diff --git a/docs/protocols/alpha.rst b/docs/protocols/alpha.rst
index 634598caf311ff82001f41ea8d3f4bca21f10d6c..7731bf7581abcc5ac824b1c48c62823802a61662 100644
--- a/docs/protocols/alpha.rst
+++ b/docs/protocols/alpha.rst
@@ -32,6 +32,9 @@ Data Availability Layer (ongoing)
 - Introduced a ``round`` field in DAL attestations, with a similar meaning as
   for consensus attestations. (MR :gl:`!11285`)
 
+- Optimize the slot header publication operation by memoizing the
+  cryptobox. (MR :gl:`!11594`)
+
 Adaptive Issuance (ongoing)
 ----------------------------
 
diff --git a/src/proto_alpha/lib_benchmarks_proto/dal_benchmarks.ml b/src/proto_alpha/lib_benchmarks_proto/dal_benchmarks.ml
index 26b8ddea158197cd96d733d7404e6cb717ba4e02..394bbc6c6af4b8f5aeca5dde713d199ae653d0fc 100644
--- a/src/proto_alpha/lib_benchmarks_proto/dal_benchmarks.ml
+++ b/src/proto_alpha/lib_benchmarks_proto/dal_benchmarks.ml
@@ -74,7 +74,7 @@ module Publish_slot_header : Benchmark.S = struct
          {slot_index; commitment; commitment_proof}
 
   let make_bench rng_state (config : config) () : workload Generator.benchmark =
-    let open Lwt_result_syntax in
+    let open Lwt_result_wrap_syntax in
     let bench_promise =
       let dal =
         {
@@ -90,7 +90,8 @@ module Publish_slot_header : Benchmark.S = struct
         | Error (`Fail msg) ->
             failwith "Dal_benchmarks: failed to initialize cryptobox (%s)" msg
       in
-
+      (* Memoize the cryptobox in the context *)
+      let*?@ ctxt, _abstract_cryptobox = Alpha_context.Dal.make ctxt in
       let* op =
         match operation_generator cryptobox rng_state with
         | Ok op -> return op
diff --git a/src/proto_alpha/lib_protocol/alpha_context.mli b/src/proto_alpha/lib_protocol/alpha_context.mli
index 9345ee7cc1b3ea5ee423d70824ae3a95e156e7b0..d3b015125674327e211eb3067c6be409fe6fcf06 100644
--- a/src/proto_alpha/lib_protocol/alpha_context.mli
+++ b/src/proto_alpha/lib_protocol/alpha_context.mli
@@ -2655,7 +2655,7 @@ module Dal : sig
 
   type cryptobox
 
-  val make : context -> cryptobox tzresult
+  val make : context -> (context * cryptobox) tzresult
 
   val number_of_slots : context -> int
 
diff --git a/src/proto_alpha/lib_protocol/dal_apply.ml b/src/proto_alpha/lib_protocol/dal_apply.ml
index c2716ade29cf15c52b4c55d73677abe646ab06a6..6e2f88994f7a646866b4206f2bdae7b1f3ef6874 100644
--- a/src/proto_alpha/lib_protocol/dal_apply.ml
+++ b/src/proto_alpha/lib_protocol/dal_apply.ml
@@ -129,7 +129,7 @@ let apply_publish_slot_header ctxt operation =
   let open Result_syntax in
   let* ctxt = Gas.consume ctxt Dal_costs.cost_Dal_publish_slot_header in
   let number_of_slots = Dal.number_of_slots ctxt in
-  let* cryptobox = Dal.make ctxt in
+  let* ctxt, cryptobox = Dal.make ctxt in
   let current_level = (Level.current ctxt).level in
   let* slot_header =
     Dal.Operations.Publish_slot_header.slot_header
diff --git a/src/proto_alpha/lib_protocol/raw_context.ml b/src/proto_alpha/lib_protocol/raw_context.ml
index 58fd927a9289964a50cf9c4c924c3149af435e4e..b81fd58726eceee948e9e328939fd77fe33eb1e0 100644
--- a/src/proto_alpha/lib_protocol/raw_context.ml
+++ b/src/proto_alpha/lib_protocol/raw_context.ml
@@ -273,6 +273,7 @@ type back = {
      dummy slot headers. *)
   dal_attestation_slot_accountability : Dal_attestation_repr.Accountability.t;
   dal_committee : dal_committee;
+  dal_cryptobox : Dal.t option;
   adaptive_issuance_enable : bool;
 }
 
@@ -887,6 +888,7 @@ let prepare ~level ~predecessor_timestamp ~timestamp ~adaptive_issuance_enable
           Dal_attestation_repr.Accountability.init
             ~length:constants.Constants_parametric_repr.dal.number_of_slots;
         dal_committee = empty_dal_committee;
+        dal_cryptobox = None;
         adaptive_issuance_enable;
       };
   }
@@ -1776,13 +1778,20 @@ module Dal = struct
 
   let make ctxt =
     let open Result_syntax in
-    let Constants_parametric_repr.{dal = {cryptobox_parameters; _}; _} =
-      ctxt.back.constants
-    in
-    match Dal.make cryptobox_parameters with
-    | Ok cryptobox -> return cryptobox
-    | Error (`Fail explanation) ->
-        tzfail (Dal_errors_repr.Dal_cryptobox_error {explanation})
+    (* Dal.make takes some time (on the order of 10ms) so we memoize
+       its result to avoid calling it more than once per block. *)
+    match ctxt.back.dal_cryptobox with
+    | Some cryptobox -> return (ctxt, cryptobox)
+    | None -> (
+        let Constants_parametric_repr.{dal = {cryptobox_parameters; _}; _} =
+          ctxt.back.constants
+        in
+        match Dal.make cryptobox_parameters with
+        | Ok cryptobox ->
+            let back = {ctxt.back with dal_cryptobox = Some cryptobox} in
+            return ({ctxt with back}, cryptobox)
+        | Error (`Fail explanation) ->
+            tzfail (Dal_errors_repr.Dal_cryptobox_error {explanation}))
 
   let number_of_slots ctxt = ctxt.back.constants.dal.number_of_slots
 
diff --git a/src/proto_alpha/lib_protocol/raw_context.mli b/src/proto_alpha/lib_protocol/raw_context.mli
index 12f7c303fcefcf41dfeac58c7e32e23378c5e7c5..327b8ed2c0a28d5c4d98e235f88134517c015bb1 100644
--- a/src/proto_alpha/lib_protocol/raw_context.mli
+++ b/src/proto_alpha/lib_protocol/raw_context.mli
@@ -428,7 +428,7 @@ end
 module Dal : sig
   type cryptobox = Dal.t
 
-  val make : t -> cryptobox tzresult
+  val make : t -> (t * cryptobox) tzresult
 
   val number_of_slots : t -> int