From c0b4685f701932c30a906d3bcead80fabaa77d6d Mon Sep 17 00:00:00 2001
From: Gabriel Moise <gabriel.moise@trili.tech>
Date: Wed, 22 Oct 2025 17:13:16 +0100
Subject: [PATCH 1/7] Dal_node: Add Not_in_committee case for elements in the
 attestable slots stream

---
 src/lib_dal_node/attestable_slots.ml   | 31 ++++++++++++++--
 src/lib_dal_node/attestable_slots.mli  | 13 +++++--
 src/lib_dal_node/block_handler.ml      | 10 +++++-
 src/lib_dal_node_services/services.ml  |  4 +--
 src/lib_dal_node_services/services.mli |  5 +--
 src/lib_dal_node_services/types.ml     | 49 +++++++++++++++++++++++---
 src/lib_dal_node_services/types.mli    | 25 +++++++++++--
 7 files changed, 120 insertions(+), 17 deletions(-)

diff --git a/src/lib_dal_node/attestable_slots.ml b/src/lib_dal_node/attestable_slots.ml
index 6fe71c51e3bc..c8c38fdafc51 100644
--- a/src/lib_dal_node/attestable_slots.ml
+++ b/src/lib_dal_node/attestable_slots.ml
@@ -133,7 +133,10 @@ let may_notify ctxt ~(slot_id : Types.slot_id) =
           let all_stored = number_stored_shards = number_of_assigned_shards in
           if not last_known_parameters.incentives_enable then (
             if all_stored then
-              T.notify attestable_slots_watcher_table pkh ~slot_id ;
+              T.notify_attestable_slot
+                attestable_slots_watcher_table
+                pkh
+                ~slot_id ;
             return_unit)
           else if not all_stored then return_unit
           else
@@ -147,8 +150,32 @@ let may_notify ctxt ~(slot_id : Types.slot_id) =
               |> Errors.to_option_tzresult
             in
             (match is_slot_attestable_with_traps with
-            | Some true -> T.notify attestable_slots_watcher_table pkh ~slot_id
+            | Some true ->
+                T.notify_attestable_slot
+                  attestable_slots_watcher_table
+                  pkh
+                  ~slot_id
             | _ -> ()) ;
             return_unit
       in
       Seq.iter_ep notify_if_attestable subscribers
+
+let may_notify_not_in_committee ctxt committee ~attestation_level =
+  let module T = Types.Attestable_slots_watcher_table in
+  let attestable_slots_watcher_table =
+    Node_context.get_attestable_slots_watcher_table ctxt
+  in
+  let subscribers = T.elements attestable_slots_watcher_table in
+  Seq.iter
+    (fun pkh ->
+      let assigned_shard_indices =
+        match Signature.Public_key_hash.Map.find pkh committee with
+        | None -> []
+        | Some (indexes, _) -> indexes
+      in
+      if List.is_empty assigned_shard_indices then
+        T.notify_no_shards_assigned
+          attestable_slots_watcher_table
+          pkh
+          ~attestation_level)
+    subscribers
diff --git a/src/lib_dal_node/attestable_slots.mli b/src/lib_dal_node/attestable_slots.mli
index fee2b7f6a783..bc59e0296d5e 100644
--- a/src/lib_dal_node/attestable_slots.mli
+++ b/src/lib_dal_node/attestable_slots.mli
@@ -21,12 +21,13 @@ val is_slot_attestable_with_traps :
   (bool, [> Errors.not_found | Errors.other]) result Lwt.t
 
 (** [subscribe ctxt ~pkh] opens a [Resto_directory.Answer] stream that yields
-    [Types.slot_id] values whenever a slot becomes attestable for [~pkh]. The stream
+    [Types.Attestable_slots_watcher_table.Attestable_event.t] values. The stream
     only emits items produced after subscription. *)
 val subscribe :
   Node_context.t ->
   pkh:Signature.public_key_hash ->
-  Types.slot_id Resto_directory.Answer.stream
+  Types.Attestable_slots_watcher_table.Attestable_event.t
+  Resto_directory.Answer.stream
 
 (** Let M = migration level (last block of the old protocol). This function
     attempts to determine whether [~published_level] is included in `[M - lag + 1 .. M]`
@@ -44,5 +45,11 @@ val attested_just_after_migration :
 
 (** [may_notify ctxt ~slot_id] checks, for each subscribed [pkh], whether all shards
     assigned to [pkh] at the attestation level corresponding to [~slot_id] are available;
-    if so, it emits [~slot_id] to that [pkh]’s stream. *)
+    if so, it emits an event to that [pkh]’s stream. *)
 val may_notify : Node_context.t -> slot_id:Types.slot_id -> unit tzresult Lwt.t
+
+(** [may_notify_not_in_committee ctxt committee ~attestation_level] checks, for each
+    subscribed [pkh], whether the delegate is in the [committee] for [~attestation_level].
+    If so, it emits an event to that [pkh]'s stream. *)
+val may_notify_not_in_committee :
+  Node_context.t -> Committee_cache.committee -> attestation_level:int32 -> unit
diff --git a/src/lib_dal_node/block_handler.ml b/src/lib_dal_node/block_handler.ml
index d0e21aaba0b6..8c2c691cb784 100644
--- a/src/lib_dal_node/block_handler.ml
+++ b/src/lib_dal_node/block_handler.ml
@@ -632,9 +632,17 @@ let new_finalized_head ctxt cctxt l1_crawler cryptobox finalized_block_hash
         Int32.(
           pred @@ add level (of_int proto_parameters.Types.attestation_lag))
       in
-      let* (_committee : (int trace * int) Signature.Public_key_hash.Map.t) =
+      let* (committee : (int trace * int) Signature.Public_key_hash.Map.t) =
         Node_context.fetch_committees ctxt ~level:attestation_level
       in
+      (* Note that, when the baker and DAL node are synchronized, then if
+         the baker is at level L, then in this function `block_level = L - 2`.
+         We therefore need the committee at `block_level + 2`. So, as long as
+         `attestation_lag > 2`, there should be no issue. *)
+      Attestable_slots.may_notify_not_in_committee
+        ctxt
+        committee
+        ~attestation_level ;
       return_unit
   in
   Gossipsub.Worker.Validate_message_hook.set_batch
diff --git a/src/lib_dal_node_services/services.ml b/src/lib_dal_node_services/services.ml
index 5d4628a13510..b66a4052c8a6 100644
--- a/src/lib_dal_node_services/services.ml
+++ b/src/lib_dal_node_services/services.ml
@@ -406,7 +406,7 @@ let get_attestable_slots :
 let monitor_attestable_slots :
     < meth : [`GET]
     ; input : unit
-    ; output : Types.slot_id
+    ; output : Types.Attestable_slots_watcher_table.Attestable_event.t
     ; prefix : unit
     ; params : unit * Signature.public_key_hash
     ; query : unit >
@@ -420,7 +420,7 @@ let monitor_attestable_slots :
        detected as traps for the baker, the slot should not be attested, so \
        the id is not sent via the stream."
     ~query:Tezos_rpc.Query.empty
-    ~output:Types.slot_id_encoding
+    ~output:Types.Attestable_slots_watcher_table.Attestable_event.encoding
     Tezos_rpc.Path.(
       open_root / "profiles" /: Signature.Public_key_hash.rpc_arg / "monitor"
       / "attestable_slots")
diff --git a/src/lib_dal_node_services/services.mli b/src/lib_dal_node_services/services.mli
index ce960fc2437a..46fe892d726a 100644
--- a/src/lib_dal_node_services/services.mli
+++ b/src/lib_dal_node_services/services.mli
@@ -223,11 +223,12 @@ val get_attestable_slots :
 (** Stream attestable slot_ids for the given public key hash [pkh].
     A slot is attestable at level [L] if it was published at [L - attestation_lag]
     and *all* shards assigned at level [L] to [pkh] are available in the DAL
-    node's store. *)
+    node's store. Returns a "not in committee" message if that is the case
+    for [pkh] at level [L]. *)
 val monitor_attestable_slots :
   < meth : [`GET]
   ; input : unit
-  ; output : Types.slot_id
+  ; output : Types.Attestable_slots_watcher_table.Attestable_event.t
   ; prefix : unit
   ; params : unit * Signature.public_key_hash
   ; query : unit >
diff --git a/src/lib_dal_node_services/types.ml b/src/lib_dal_node_services/types.ml
index 7a7b00e5e41d..827db5c3305b 100644
--- a/src/lib_dal_node_services/types.ml
+++ b/src/lib_dal_node_services/types.ml
@@ -780,15 +780,48 @@ module SlotIdSet =
     end)
 
 module Attestable_slots_watcher_table = struct
+  module Attestable_event = struct
+    type t =
+      | Attestable_slot of {slot_id : slot_id}
+      | No_shards_assigned of {attestation_level : level}
+
+    let encoding =
+      let open Data_encoding in
+      union
+        [
+          case
+            ~title:"attestable_slot"
+            (Tag 0)
+            (obj2
+               (req "kind" (constant "attestable_slot"))
+               (req "slot_id" slot_id_encoding))
+            (function
+              | Attestable_slot {slot_id} -> Some ((), slot_id) | _ -> None)
+            (fun ((), slot_id) -> Attestable_slot {slot_id});
+          case
+            ~title:"no_shards_assigned"
+            (Tag 1)
+            (obj2
+               (req "kind" (constant "no_shards_assigned"))
+               (req "attestation_level" int32))
+            (function
+              | No_shards_assigned {attestation_level} ->
+                  Some ((), attestation_level)
+              | _ -> None)
+            (fun ((), attestation_level) ->
+              No_shards_assigned {attestation_level});
+        ]
+  end
+
   (** A watcher used to stream newly-attestable slots for a given delegate (pkh).
       - [stream] is the push endpoint used by the DAL node to notify consumers
-        (RPC layer / baker) that a specific [slot_id] has become attestable.
+        (RPC layer / baker) with [attestable_event] information.
       - [num_subscribers] is the number of active consumers currently subscribed to
         this pkh’s stream.
       - [notified_slots] is an LRU set of slot ids already notified, so that we avoid
         sending duplicates in the stream. *)
   type watcher = {
-    stream : slot_id Lwt_watcher.input;
+    stream : Attestable_event.t Lwt_watcher.input;
     mutable num_subscribers : int;
     notified_slots : SlotIdSet.t;
   }
@@ -829,13 +862,21 @@ module Attestable_slots_watcher_table = struct
         Signature.Public_key_hash.Table.add t pkh watcher ;
         watcher
 
-  let notify t pkh ~slot_id =
+  let notify_attestable_slot t pkh ~slot_id =
     match Signature.Public_key_hash.Table.find t pkh with
     | None -> ()
     | Some watcher ->
         if not @@ SlotIdSet.mem watcher.notified_slots slot_id then (
           SlotIdSet.add watcher.notified_slots slot_id ;
-          Lwt_watcher.notify watcher.stream slot_id)
+          Lwt_watcher.notify watcher.stream (Attestable_slot {slot_id}))
+
+  let notify_no_shards_assigned t pkh ~attestation_level =
+    match Signature.Public_key_hash.Table.find t pkh with
+    | None -> ()
+    | Some watcher ->
+        Lwt_watcher.notify
+          watcher.stream
+          (No_shards_assigned {attestation_level})
 
   let remove = Signature.Public_key_hash.Table.remove
 
diff --git a/src/lib_dal_node_services/types.mli b/src/lib_dal_node_services/types.mli
index cf89aec1294f..262e20632984 100644
--- a/src/lib_dal_node_services/types.mli
+++ b/src/lib_dal_node_services/types.mli
@@ -411,10 +411,22 @@ module Health : sig
 end
 
 module Attestable_slots_watcher_table : sig
+  module Attestable_event : sig
+    (** DAL attestability items emitted on a per-delegate stream.
+      The delegate is implicit, as each stream is bound to a single delegate. *)
+    type t =
+      | Attestable_slot of {slot_id : slot_id}
+          (** the [slot_id] is now attestable for the delegate *)
+      | No_shards_assigned of {attestation_level : level}
+          (** the delegate has no assigned shards at [attestation_level] *)
+
+    val encoding : t Data_encoding.t
+  end
+
   type watcher
 
   (** Returns the stream currently stored in the watcher. *)
-  val get_stream : watcher -> slot_id Lwt_watcher.input
+  val get_stream : watcher -> Attestable_event.t Lwt_watcher.input
 
   (** Returns the number of subscribers to the stream currently stored in the watcher. *)
   val get_num_subscribers : watcher -> shard_index
@@ -435,8 +447,15 @@ module Attestable_slots_watcher_table : sig
   val get_or_init :
     t -> Signature.public_key_hash -> proto_parameters option -> watcher
 
-  (** [notify t pkh ~slot_id] pushes [slot_id] to the stream for [pkh] if present. *)
-  val notify : t -> Signature.public_key_hash -> slot_id:slot_id -> unit
+  (** [notify_attestable_slot t pkh ~slot_id] pushes an [Attestable_slot] event for [~slot_id]
+      to the stream for [pkh], if present. *)
+  val notify_attestable_slot :
+    t -> Signature.public_key_hash -> slot_id:slot_id -> unit
+
+  (** [notify_no_shards_assigned t pkh ~attestation_level] pushes a [No_shards_assigned] event for
+      [~attestation_level] to the stream for [pkh], if present. *)
+  val notify_no_shards_assigned :
+    t -> Signature.public_key_hash -> attestation_level:level -> unit
 
   (** [remove t pkh] removes the watcher entry for [pkh] from [t] if present. *)
   val remove : t -> Signature.public_key_hash -> unit
-- 
GitLab


From 7bf4a7166efeae55674576539db15a1fe1c110fa Mon Sep 17 00:00:00 2001
From: Gabriel Moise <gabriel.moise@trili.tech>
Date: Mon, 27 Oct 2025 14:53:21 +0000
Subject: [PATCH 2/7] Dal_node: Attestable_slots: Refactor is_attestable_slot
 function

---
 src/lib_dal_node/attestable_slots.ml | 122 +++++++++++++--------------
 1 file changed, 60 insertions(+), 62 deletions(-)

diff --git a/src/lib_dal_node/attestable_slots.ml b/src/lib_dal_node/attestable_slots.ml
index c8c38fdafc51..f7c4b4bc1f7e 100644
--- a/src/lib_dal_node/attestable_slots.ml
+++ b/src/lib_dal_node/attestable_slots.ml
@@ -89,76 +89,74 @@ let attested_just_after_migration ctxt ~attested_level =
     && migration_level < attested_level
     && attested_level <= Int32.add migration_level new_lag)
 
-let may_notify ctxt ~(slot_id : Types.slot_id) =
+(** [is_attestable_slot ctxt ~pkh ~slot_id] decides whether [~slot_id] is
+    attestable for delegate [pkh] at the time of calling. *)
+let is_attestable_slot ctxt ~pkh ~(slot_id : Types.slot_id) =
   let open Lwt_result_syntax in
   let open Node_context in
+  let published_level = slot_id.slot_level in
+  let*? lag = get_attestation_lag ctxt ~level:published_level in
+  let attested_level = Int32.(add published_level lag) in
+  let attestation_level = Int32.pred attested_level in
+  let*? should_drop = published_just_before_migration ctxt ~published_level in
+  if should_drop then return_false
+  else
+    let*? last_known_parameters =
+      get_proto_parameters ctxt ~level:(`Level attested_level)
+    in
+    let shards_store = Store.shards (get_store ctxt) in
+    (* For retrieving the assigned shard indexes, we consider the committee
+       at [attestation_level], because the (DAL) attestations in the blocks
+       at level [attested_level] refer to the predecessor level. *)
+    let* shard_indices =
+      fetch_assigned_shard_indices ctxt ~pkh ~level:attestation_level
+    in
+    let number_of_assigned_shards = List.length shard_indices in
+    if number_of_assigned_shards = 0 || published_level < 1l then return_false
+    else
+      let* number_stored_shards =
+        Store.Shards.number_of_shards_available
+          shards_store
+          slot_id
+          shard_indices
+      in
+      let all_stored = number_stored_shards = number_of_assigned_shards in
+      if not last_known_parameters.incentives_enable then return all_stored
+      else if not all_stored then return_false
+      else
+        let* is_slot_attestable_with_traps =
+          is_slot_attestable_with_traps
+            shards_store
+            last_known_parameters.traps_fraction
+            pkh
+            shard_indices
+            slot_id
+          |> Errors.to_option_tzresult
+        in
+        match is_slot_attestable_with_traps with
+        | Some true -> return_true
+        | _ -> return_false
+
+let may_notify ctxt ~(slot_id : Types.slot_id) =
+  let open Lwt_result_syntax in
   let module T = Types.Attestable_slots_watcher_table in
   let attestable_slots_watcher_table =
-    get_attestable_slots_watcher_table ctxt
+    Node_context.get_attestable_slots_watcher_table ctxt
   in
   let subscribers = T.elements attestable_slots_watcher_table in
   if Seq.is_empty subscribers then return_unit
   else
-    let published_level = slot_id.slot_level in
-    let*? lag = get_attestation_lag ctxt ~level:published_level in
-    let attested_level = Int32.(add published_level lag) in
-    let attestation_level = Int32.pred attested_level in
-    let*? should_drop = published_just_before_migration ctxt ~published_level in
-    if should_drop then return_unit
-    else
-      let*? last_known_parameters =
-        get_proto_parameters ctxt ~level:(`Level attested_level)
-      in
-      let shards_store = Store.shards (get_store ctxt) in
-      (* For each subscribed pkh, if it has assigned shards for that level,
-         check if all those shards are available for [slot_id] and notify watcher,
-         accordingly. *)
-      let notify_if_attestable pkh =
-        (* For retrieving the assigned shard indexes, we consider the committee
-           at [attestation_level], because the (DAL) attestations in the blocks
-           at level [attested_level] refer to the predecessor level. *)
-        let* shard_indices =
-          fetch_assigned_shard_indices ctxt ~pkh ~level:attestation_level
-        in
-        let number_of_assigned_shards = List.length shard_indices in
-        if number_of_assigned_shards = 0 then return_unit
-        else if published_level < 1l then return_unit
-        else
-          let* number_stored_shards =
-            Store.Shards.number_of_shards_available
-              shards_store
-              slot_id
-              shard_indices
-          in
-          let all_stored = number_stored_shards = number_of_assigned_shards in
-          if not last_known_parameters.incentives_enable then (
-            if all_stored then
-              T.notify_attestable_slot
-                attestable_slots_watcher_table
-                pkh
-                ~slot_id ;
-            return_unit)
-          else if not all_stored then return_unit
-          else
-            let* is_slot_attestable_with_traps =
-              is_slot_attestable_with_traps
-                shards_store
-                last_known_parameters.traps_fraction
-                pkh
-                shard_indices
-                slot_id
-              |> Errors.to_option_tzresult
-            in
-            (match is_slot_attestable_with_traps with
-            | Some true ->
-                T.notify_attestable_slot
-                  attestable_slots_watcher_table
-                  pkh
-                  ~slot_id
-            | _ -> ()) ;
-            return_unit
-      in
-      Seq.iter_ep notify_if_attestable subscribers
+    let notify_attestable_slot pkh =
+      let* is_attestable_slot = is_attestable_slot ctxt ~pkh ~slot_id in
+      if is_attestable_slot then
+        T.notify_attestable_slot attestable_slots_watcher_table pkh ~slot_id
+      else () ;
+      return_unit
+    in
+    (* For each subscribed pkh, if it has assigned shards for that level,
+       check if all those shards are available for [slot_id] and notify watcher,
+       accordingly. *)
+    Seq.iter_ep notify_attestable_slot subscribers
 
 let may_notify_not_in_committee ctxt committee ~attestation_level =
   let module T = Types.Attestable_slots_watcher_table in
-- 
GitLab


From c054886bfc890bc396e8ccb34de07af694fe050c Mon Sep 17 00:00:00 2001
From: Gabriel Moise <gabriel.moise@trili.tech>
Date: Mon, 27 Oct 2025 14:57:06 +0000
Subject: [PATCH 3/7] Dal_node: Attestable_slots: Refactor is_not_in_committee
 function

---
 src/lib_dal_node/attestable_slots.ml | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/lib_dal_node/attestable_slots.ml b/src/lib_dal_node/attestable_slots.ml
index f7c4b4bc1f7e..9959e34466ef 100644
--- a/src/lib_dal_node/attestable_slots.ml
+++ b/src/lib_dal_node/attestable_slots.ml
@@ -158,6 +158,14 @@ let may_notify ctxt ~(slot_id : Types.slot_id) =
        accordingly. *)
     Seq.iter_ep notify_attestable_slot subscribers
 
+let is_not_in_committee committee ~pkh =
+  let assigned_shard_indices =
+    match Signature.Public_key_hash.Map.find pkh committee with
+    | None -> []
+    | Some (indexes, _) -> indexes
+  in
+  List.is_empty assigned_shard_indices
+
 let may_notify_not_in_committee ctxt committee ~attestation_level =
   let module T = Types.Attestable_slots_watcher_table in
   let attestable_slots_watcher_table =
@@ -166,12 +174,7 @@ let may_notify_not_in_committee ctxt committee ~attestation_level =
   let subscribers = T.elements attestable_slots_watcher_table in
   Seq.iter
     (fun pkh ->
-      let assigned_shard_indices =
-        match Signature.Public_key_hash.Map.find pkh committee with
-        | None -> []
-        | Some (indexes, _) -> indexes
-      in
-      if List.is_empty assigned_shard_indices then
+      if is_not_in_committee committee ~pkh then
         T.notify_no_shards_assigned
           attestable_slots_watcher_table
           pkh
-- 
GitLab


From ca0758aa33fae0ee292a38f73cc38a948a8f51a3 Mon Sep 17 00:00:00 2001
From: Gabriel Moise <gabriel.moise@trili.tech>
Date: Mon, 27 Oct 2025 14:58:35 +0000
Subject: [PATCH 4/7] Dal_node: Change is_slot_attestable_with_traps function
 name

---
 src/lib_dal_node/RPC_server.ml        |  2 +-
 src/lib_dal_node/attestable_slots.ml  | 10 +++++-----
 src/lib_dal_node/attestable_slots.mli |  4 ++--
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/lib_dal_node/RPC_server.ml b/src/lib_dal_node/RPC_server.ml
index e4e9e0f8300e..e50e5e1adf92 100644
--- a/src/lib_dal_node/RPC_server.ml
+++ b/src/lib_dal_node/RPC_server.ml
@@ -466,7 +466,7 @@ module Profile_handlers = struct
                   return all_stored
                 else if not all_stored then return false
                 else
-                  Attestable_slots.is_slot_attestable_with_traps
+                  Attestable_slots.is_attestable_slot_with_traps
                     shards_store
                     last_known_parameters.traps_fraction
                     pkh
diff --git a/src/lib_dal_node/attestable_slots.ml b/src/lib_dal_node/attestable_slots.ml
index 9959e34466ef..c33ec9bd7a7f 100644
--- a/src/lib_dal_node/attestable_slots.ml
+++ b/src/lib_dal_node/attestable_slots.ml
@@ -5,7 +5,7 @@
 (*                                                                           *)
 (*****************************************************************************)
 
-let is_slot_attestable_with_traps shards_store traps_fraction pkh
+let is_attestable_slot_with_traps shards_store traps_fraction pkh
     assigned_shard_indexes slot_id =
   let open Lwt_result_syntax in
   List.for_all_es
@@ -14,7 +14,7 @@ let is_slot_attestable_with_traps shards_store traps_fraction pkh
         Store.Shards.read shards_store slot_id shard_index
       in
       (* Note: here [pkh] should identify the baker using its delegate key
-           (not the consensus key) *)
+        (not the consensus key) *)
       let trap_res = Trap.share_is_trap pkh share ~traps_fraction in
       match trap_res with
       | Ok true ->
@@ -124,8 +124,8 @@ let is_attestable_slot ctxt ~pkh ~(slot_id : Types.slot_id) =
       if not last_known_parameters.incentives_enable then return all_stored
       else if not all_stored then return_false
       else
-        let* is_slot_attestable_with_traps =
-          is_slot_attestable_with_traps
+        let* is_attestable_slot_with_traps =
+          is_attestable_slot_with_traps
             shards_store
             last_known_parameters.traps_fraction
             pkh
@@ -133,7 +133,7 @@ let is_attestable_slot ctxt ~pkh ~(slot_id : Types.slot_id) =
             slot_id
           |> Errors.to_option_tzresult
         in
-        match is_slot_attestable_with_traps with
+        match is_attestable_slot_with_traps with
         | Some true -> return_true
         | _ -> return_false
 
diff --git a/src/lib_dal_node/attestable_slots.mli b/src/lib_dal_node/attestable_slots.mli
index bc59e0296d5e..b1dd9ddb0a61 100644
--- a/src/lib_dal_node/attestable_slots.mli
+++ b/src/lib_dal_node/attestable_slots.mli
@@ -5,14 +5,14 @@
 (*                                                                           *)
 (*****************************************************************************)
 
-(** [is_slot_attestable_with_traps shards_store traps_fraction pkh
+(** [is_attestable_slot_with_traps shards_store traps_fraction pkh
     assigned_shard_indexes slot_id] checks whether the slot identified by [slot_id]
     is attestable for delegate [pkh] with respect to the traps mechanism.
 
     The function iterates over the delegate’s [assigned_shard_indexes], reads each
     corresponding stored shard share from [shards_store], and evaluates
     [Trap.share_is_trap] on it using [traps_fraction].  *)
-val is_slot_attestable_with_traps :
+val is_attestable_slot_with_traps :
   Store.Shards.t ->
   Q.t ->
   Signature.public_key_hash ->
-- 
GitLab


From 18a035a78a9ce36f0cb02804539f63b5ec1f900f Mon Sep 17 00:00:00 2001
From: Gabriel Moise <gabriel.moise@trili.tech>
Date: Mon, 27 Oct 2025 15:03:58 +0000
Subject: [PATCH 5/7] Dal_node: Add Slot_has_trap case for elements in the
 attestable slots stream

---
 src/lib_dal_node/attestable_slots.ml | 38 +++++++++++++++++-----------
 src/lib_dal_node_services/types.ml   | 18 +++++++++++++
 src/lib_dal_node_services/types.mli  |  7 +++++
 3 files changed, 48 insertions(+), 15 deletions(-)

diff --git a/src/lib_dal_node/attestable_slots.ml b/src/lib_dal_node/attestable_slots.ml
index c33ec9bd7a7f..3a3bf32c8208 100644
--- a/src/lib_dal_node/attestable_slots.ml
+++ b/src/lib_dal_node/attestable_slots.ml
@@ -89,9 +89,10 @@ let attested_just_after_migration ctxt ~attested_level =
     && migration_level < attested_level
     && attested_level <= Int32.add migration_level new_lag)
 
-(** [is_attestable_slot ctxt ~pkh ~slot_id] decides whether [~slot_id] is
-    attestable for delegate [pkh] at the time of calling. *)
-let is_attestable_slot ctxt ~pkh ~(slot_id : Types.slot_id) =
+(** [is_attestable_slot_or_trap ctxt ~pkh ~slot_id] decides whether [~slot_id] is
+    attestable for delegate [pkh] at the time of calling, and when DAL incentives
+    are enabled, whether it should be considered as a trap. *)
+let is_attestable_slot_or_trap ctxt ~pkh ~(slot_id : Types.slot_id) =
   let open Lwt_result_syntax in
   let open Node_context in
   let published_level = slot_id.slot_level in
@@ -99,7 +100,7 @@ let is_attestable_slot ctxt ~pkh ~(slot_id : Types.slot_id) =
   let attested_level = Int32.(add published_level lag) in
   let attestation_level = Int32.pred attested_level in
   let*? should_drop = published_just_before_migration ctxt ~published_level in
-  if should_drop then return_false
+  if should_drop then return_none
   else
     let*? last_known_parameters =
       get_proto_parameters ctxt ~level:(`Level attested_level)
@@ -112,7 +113,7 @@ let is_attestable_slot ctxt ~pkh ~(slot_id : Types.slot_id) =
       fetch_assigned_shard_indices ctxt ~pkh ~level:attestation_level
     in
     let number_of_assigned_shards = List.length shard_indices in
-    if number_of_assigned_shards = 0 || published_level < 1l then return_false
+    if number_of_assigned_shards = 0 || published_level < 1l then return_none
     else
       let* number_stored_shards =
         Store.Shards.number_of_shards_available
@@ -121,8 +122,9 @@ let is_attestable_slot ctxt ~pkh ~(slot_id : Types.slot_id) =
           shard_indices
       in
       let all_stored = number_stored_shards = number_of_assigned_shards in
-      if not last_known_parameters.incentives_enable then return all_stored
-      else if not all_stored then return_false
+      if not last_known_parameters.incentives_enable then
+        if all_stored then return_some `Attestable_slot else return_none
+      else if not all_stored then return_none
       else
         let* is_attestable_slot_with_traps =
           is_attestable_slot_with_traps
@@ -134,8 +136,9 @@ let is_attestable_slot ctxt ~pkh ~(slot_id : Types.slot_id) =
           |> Errors.to_option_tzresult
         in
         match is_attestable_slot_with_traps with
-        | Some true -> return_true
-        | _ -> return_false
+        | Some true -> return_some `Attestable_slot
+        | Some false -> return_some `Trap
+        | None -> return_none
 
 let may_notify ctxt ~(slot_id : Types.slot_id) =
   let open Lwt_result_syntax in
@@ -146,17 +149,22 @@ let may_notify ctxt ~(slot_id : Types.slot_id) =
   let subscribers = T.elements attestable_slots_watcher_table in
   if Seq.is_empty subscribers then return_unit
   else
-    let notify_attestable_slot pkh =
-      let* is_attestable_slot = is_attestable_slot ctxt ~pkh ~slot_id in
-      if is_attestable_slot then
-        T.notify_attestable_slot attestable_slots_watcher_table pkh ~slot_id
-      else () ;
+    let notify_slot_attestable_or_trap pkh =
+      let* is_attestable_slot_or_trap =
+        is_attestable_slot_or_trap ctxt ~pkh ~slot_id
+      in
+      (match is_attestable_slot_or_trap with
+      | Some `Attestable_slot ->
+          T.notify_attestable_slot attestable_slots_watcher_table pkh ~slot_id
+      | Some `Trap ->
+          T.notify_slot_has_trap attestable_slots_watcher_table pkh ~slot_id
+      | None -> ()) ;
       return_unit
     in
     (* For each subscribed pkh, if it has assigned shards for that level,
        check if all those shards are available for [slot_id] and notify watcher,
        accordingly. *)
-    Seq.iter_ep notify_attestable_slot subscribers
+    Seq.iter_ep notify_slot_attestable_or_trap subscribers
 
 let is_not_in_committee committee ~pkh =
   let assigned_shard_indices =
diff --git a/src/lib_dal_node_services/types.ml b/src/lib_dal_node_services/types.ml
index 827db5c3305b..04837ed544c9 100644
--- a/src/lib_dal_node_services/types.ml
+++ b/src/lib_dal_node_services/types.ml
@@ -784,6 +784,7 @@ module Attestable_slots_watcher_table = struct
     type t =
       | Attestable_slot of {slot_id : slot_id}
       | No_shards_assigned of {attestation_level : level}
+      | Slot_has_trap of {slot_id : slot_id}
 
     let encoding =
       let open Data_encoding in
@@ -810,6 +811,15 @@ module Attestable_slots_watcher_table = struct
               | _ -> None)
             (fun ((), attestation_level) ->
               No_shards_assigned {attestation_level});
+          case
+            ~title:"slot_has_trap"
+            (Tag 2)
+            (obj2
+               (req "kind" (constant "slot_has_trap"))
+               (req "slot_id" slot_id_encoding))
+            (function
+              | Slot_has_trap {slot_id} -> Some ((), slot_id) | _ -> None)
+            (fun ((), slot_id) -> Slot_has_trap {slot_id});
         ]
   end
 
@@ -878,6 +888,14 @@ module Attestable_slots_watcher_table = struct
           watcher.stream
           (No_shards_assigned {attestation_level})
 
+  let notify_slot_has_trap t pkh ~slot_id =
+    match Signature.Public_key_hash.Table.find t pkh with
+    | None -> ()
+    | Some watcher ->
+        if not @@ SlotIdSet.mem watcher.notified_slots slot_id then (
+          SlotIdSet.add watcher.notified_slots slot_id ;
+          Lwt_watcher.notify watcher.stream (Slot_has_trap {slot_id}))
+
   let remove = Signature.Public_key_hash.Table.remove
 
   let elements = Signature.Public_key_hash.Table.to_seq_keys
diff --git a/src/lib_dal_node_services/types.mli b/src/lib_dal_node_services/types.mli
index 262e20632984..3990fe7119f0 100644
--- a/src/lib_dal_node_services/types.mli
+++ b/src/lib_dal_node_services/types.mli
@@ -419,6 +419,8 @@ module Attestable_slots_watcher_table : sig
           (** the [slot_id] is now attestable for the delegate *)
       | No_shards_assigned of {attestation_level : level}
           (** the delegate has no assigned shards at [attestation_level] *)
+      | Slot_has_trap of {slot_id : slot_id}
+          (** the [slot_id] is a trap for the delegate *)
 
     val encoding : t Data_encoding.t
   end
@@ -457,6 +459,11 @@ module Attestable_slots_watcher_table : sig
   val notify_no_shards_assigned :
     t -> Signature.public_key_hash -> attestation_level:level -> unit
 
+  (** [notify_slot_has_trap t pkh ~slot_id] pushed a [Slot_has_trap] event for [~slot_id] to the
+      stream for [pkh], if present. *)
+  val notify_slot_has_trap :
+    t -> Signature.public_key_hash -> slot_id:slot_id -> unit
+
   (** [remove t pkh] removes the watcher entry for [pkh] from [t] if present. *)
   val remove : t -> Signature.public_key_hash -> unit
 
-- 
GitLab


From 7707b91a37b2c66f8b42424e60e4981358ec71c0 Mon Sep 17 00:00:00 2001
From: Gabriel Moise <gabriel.moise@trili.tech>
Date: Mon, 27 Oct 2025 15:05:13 +0000
Subject: [PATCH 6/7] Dal_node: Attestable_slots: Rename may_notify function to
 be more explicit

---
 src/lib_dal_node/amplificator.ml      | 6 +++++-
 src/lib_dal_node/attestable_slots.ml  | 2 +-
 src/lib_dal_node/attestable_slots.mli | 9 +++++----
 src/lib_dal_node/daemon.ml            | 4 +++-
 src/lib_dal_node/slot_manager.ml      | 4 +++-
 5 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/src/lib_dal_node/amplificator.ml b/src/lib_dal_node/amplificator.ml
index 59853a96ffb2..9847cc5914be 100644
--- a/src/lib_dal_node/amplificator.ml
+++ b/src/lib_dal_node/amplificator.ml
@@ -405,7 +405,11 @@ let reply_receiver_job {process; query_store; _} node_context =
           Store.Shards.write_all (Store.shards node_store) slot_id shards
           |> Errors.to_tzresult
         in
-        let* () = Attestable_slots.may_notify node_context ~slot_id in
+        let* () =
+          Attestable_slots.may_notify_attestable_slot_or_trap
+            node_context
+            ~slot_id
+        in
         let level_committee ~level =
           let* res = Node_context.fetch_committees node_context ~level in
           return (Signature.Public_key_hash.Map.map fst res)
diff --git a/src/lib_dal_node/attestable_slots.ml b/src/lib_dal_node/attestable_slots.ml
index 3a3bf32c8208..a65569aec2c4 100644
--- a/src/lib_dal_node/attestable_slots.ml
+++ b/src/lib_dal_node/attestable_slots.ml
@@ -140,7 +140,7 @@ let is_attestable_slot_or_trap ctxt ~pkh ~(slot_id : Types.slot_id) =
         | Some false -> return_some `Trap
         | None -> return_none
 
-let may_notify ctxt ~(slot_id : Types.slot_id) =
+let may_notify_attestable_slot_or_trap ctxt ~(slot_id : Types.slot_id) =
   let open Lwt_result_syntax in
   let module T = Types.Attestable_slots_watcher_table in
   let attestable_slots_watcher_table =
diff --git a/src/lib_dal_node/attestable_slots.mli b/src/lib_dal_node/attestable_slots.mli
index b1dd9ddb0a61..3e0f75caa0ad 100644
--- a/src/lib_dal_node/attestable_slots.mli
+++ b/src/lib_dal_node/attestable_slots.mli
@@ -43,10 +43,11 @@ val published_just_before_migration :
 val attested_just_after_migration :
   Node_context.t -> attested_level:int32 -> bool tzresult
 
-(** [may_notify ctxt ~slot_id] checks, for each subscribed [pkh], whether all shards
-    assigned to [pkh] at the attestation level corresponding to [~slot_id] are available;
-    if so, it emits an event to that [pkh]’s stream. *)
-val may_notify : Node_context.t -> slot_id:Types.slot_id -> unit tzresult Lwt.t
+(** [may_notify_attestable_slot_or_trap ctxt ~slot_id] checks, for each subscribed [pkh],
+    whether all shards assigned to [pkh] at the attestation level corresponding to [~slot_id]
+    are available; if so, it emits an event to that [pkh]’s stream. *)
+val may_notify_attestable_slot_or_trap :
+  Node_context.t -> slot_id:Types.slot_id -> unit tzresult Lwt.t
 
 (** [may_notify_not_in_committee ctxt committee ~attestation_level] checks, for each
     subscribed [pkh], whether the delegate is in the [committee] for [~attestation_level].
diff --git a/src/lib_dal_node/daemon.ml b/src/lib_dal_node/daemon.ml
index 61190e375f27..3f051ce87b4e 100644
--- a/src/lib_dal_node/daemon.ml
+++ b/src/lib_dal_node/daemon.ml
@@ -163,7 +163,9 @@ let connect_gossipsub_with_p2p proto_parameters gs_worker transport_layer
           [@profiler.aggregate_s
             {verbosity = Notice; profiler_module = Profiler} "save_and_notify"]
         in
-        let* () = Attestable_slots.may_notify node_ctxt ~slot_id in
+        let* () =
+          Attestable_slots.may_notify_attestable_slot_or_trap node_ctxt ~slot_id
+        in
         (* Introduce a new store read at each received shard. Not sure it can be
           a problem, though *)
         let* number_of_already_stored_shards =
diff --git a/src/lib_dal_node/slot_manager.ml b/src/lib_dal_node/slot_manager.ml
index 6661c29cc5c8..5f4029bbddc8 100644
--- a/src/lib_dal_node/slot_manager.ml
+++ b/src/lib_dal_node/slot_manager.ml
@@ -737,7 +737,9 @@ let publish_slot_data ctxt ~level_committee ~slot_size gs_worker
         Store.Shards.write_all (Store.shards node_store) slot_id shards
         |> Errors.to_tzresult
       in
-      let* () = Attestable_slots.may_notify ctxt ~slot_id in
+      let* () =
+        Attestable_slots.may_notify_attestable_slot_or_trap ctxt ~slot_id
+      in
       let* () =
         Store.Slots.add_slot ~slot_size (Store.slots node_store) slot slot_id
         |> Errors.to_tzresult
-- 
GitLab


From 898299bae8ded25398cc65474f07e0206a678624 Mon Sep 17 00:00:00 2001
From: Gabriel Moise <gabriel.moise@trili.tech>
Date: Wed, 29 Oct 2025 10:39:26 +0000
Subject: [PATCH 7/7] Dal_node: Simplify if-else logic

---
 src/lib_dal_node/attestable_slots.ml | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/lib_dal_node/attestable_slots.ml b/src/lib_dal_node/attestable_slots.ml
index a65569aec2c4..a2650c801f1d 100644
--- a/src/lib_dal_node/attestable_slots.ml
+++ b/src/lib_dal_node/attestable_slots.ml
@@ -122,9 +122,9 @@ let is_attestable_slot_or_trap ctxt ~pkh ~(slot_id : Types.slot_id) =
           shard_indices
       in
       let all_stored = number_stored_shards = number_of_assigned_shards in
-      if not last_known_parameters.incentives_enable then
-        if all_stored then return_some `Attestable_slot else return_none
-      else if not all_stored then return_none
+      if not all_stored then return_none
+      else if not last_known_parameters.incentives_enable then
+        return_some `Attestable_slot
       else
         let* is_attestable_slot_with_traps =
           is_attestable_slot_with_traps
-- 
GitLab