diff --git a/.dockerignore b/.dockerignore
index 51b0b2efdb76903cc2f9d1c08fdb65c138639da4..89ac970188f7ee8d9db08cec0c3c6e426402425c 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -51,6 +51,7 @@ _coverage_report
 **/*.orig
 
 .idea
+.vscode
 # .venv directories are created by poetry if the option in-project is set to
 # true.
 **/.venv
diff --git a/.gitignore b/.gitignore
index 0a83d42f621d340734c3e52592e705aebf1807a7..79d441df0a71b812f7521d51e2537bdeb8a4b975 100644
--- a/.gitignore
+++ b/.gitignore
@@ -61,6 +61,7 @@ __pycache__
 *.orig
 
 .idea
+.vscode
 # .venv directories are created by poetry if the option in-project is set to true.
 **/.venv
 **/.mypy_cache/
diff --git a/docs/alpha/event.rst b/docs/alpha/event.rst
new file mode 100644
index 0000000000000000000000000000000000000000..5c9d28405c41caf40393eac0d6e0f02b6a8d4f8b
--- /dev/null
+++ b/docs/alpha/event.rst
@@ -0,0 +1,118 @@
+Contract event logging
+======================
+
+Contract event logging is a way for contracts to deliver event-like information to external applications.
+This mechanism allows off-chain applications to react to Tezos contracts execution.
+
+Event address
+-------------
+On the Tezos chain, an event is uniquely identified with a 53-byte long base58 address starting with ``ev1``.
+This address is computed from an event schema and an event tag (see below for details).
+An event schema is a Micheline expression denoting the Michelson type of the event data attachment.
+For instance, this schema could be ``or (nat %int) (string %str)`` in Micheline.
+An event tag is an identifier represented by a string, such as ``writeOut`` or ``mintToken``.
+
+Computing an event address
+--------------------------
+An address for a event is computed from a Base58 32-byte hash of the binary serialization of
+the original Michelson node, with all annotations, separated by a ``0x05`` byte.
+
+For instance, the following event schema declaration produces a unique address of
+``ev12m5E1yW14mc9rsrcdGAWVfDSdmRGuctykrVU55bHZBGv9kmdhW``, which is a Base58-encoded Blake2b hash of
+a ``0x05`` byte and then followed by the binary serialization of ``or (nat %int) (string %str)``
+with all the annotations ``%int`` and ``%str``.
+
+::
+    %tag1 (or (nat %int) (string %str));
+
+Alternatively, there is a RPC exposed by the node for computing this address.
+Make a ``POST`` request to ``helpers/scripts/event_address`` with a JSON payload of shape
+``{"type": "<Michelson data type>"}``, and it will return a JSON response of shape
+``{"address": "ev1..."}``.
+
+Sending events
+--------------
+Contract events can be emitted by invoking the Michelson instruction ``EMIT``.
+``EMIT %tag ty`` pops an item of type ``ty`` off the stack and pushes an ``operation`` onto the stack.
+
+``EMIT`` has the following typing rule.
+
+::
+    EMIT %tag ty :: 'ty : 'S -> operation : 'S
+
+To actually send out the events, most importantly, the produced ``operation``\s must be included into the list of
+operations that the main contract code returns along with other ``operation``\s that this contract wants to effect.
+
+Event
+-----
+A contract event in Tezos consists of the following data.
+
+- An event ``data`` of a certain type ``event``.
+- An event address associated with a certain event tag and data type.
+
+Each successful contract execution attaches into the transaction receipt a list of contract events
+arranged in the order of appearance in the resultant list of operations.
+There, the events are made ready for consumption by services observing the chain.
+
+Example
+-------
+Suppose a contract wants to emit events with the following type for the data attachment.
+
+::
+    or (nat %int) (string %str);
+
+Then, this contract may generate an event emission operation with the following instructions.
+Note that the ``EMIT`` instruction will emit an event with a tag ``notify_client``.
+
+::
+    PUSH string "right";
+    RIGHT nat;
+    EMIT %notify_client (or (nat %int) (string %str));
+
+
+Retrieving events
+-----------------
+Events successfully emitted can be read off directly from transaction results.
+This is typically achieved by making JSON RPCs to the block service.
+It will return a list of operations, each including the event entries with the information above.
+
+Here is a sample result from a call.
+
+::
+
+    {
+      "protocol": "ProtoALphaALphaALphaALphaALphaALphaALphaALphaDdp3zK",
+      "hash": "opNX59asPwNZGu2kFiHFVJzn7QwtyaExoLtxdZSm3Q3o4jDdSmo",
+      // ... fields elided for brevity
+      "contents": [
+        {
+          "kind": "transaction",
+          // ... fields elided for brevity
+          "metadata": {
+            // ... fields elided for brevity
+            "internal_operation_results": [
+              {
+                "status": "applied",
+                // ... fields elided for brevity
+                "source": "KT...",
+                "destination": "ev1...",                            // <~
+                "parameters": {                                     // <~
+                  "entrypoint": "event_tag...",                     // <~
+                  "value": {                                        // <~
+                    "prim": "Right",                                // <~
+                    "args": [                                       // <~
+                      {                                             // <~
+                        "string": "right"                           // <~
+                      }                                             // <~
+                    ]                                               // <~
+                  }                                                 // <~
+                }                                                   // <~
+              }
+            ]
+          }
+        }
+      ]
+    }
+
+Note that the ``operation`` produced by ``EMIT`` does not constitute a call to any other contract.
+Events emitted with ``EMIT`` is optimized to avoid calls to external contracts to reduce gas usage.
diff --git a/docs/alpha/michelson.rst b/docs/alpha/michelson.rst
index 8e6812ba32d811ba8f641bd344c0f7eb94190229..6b5d875efdf524725e333d6aaad21882a460bb6e 100644
--- a/docs/alpha/michelson.rst
+++ b/docs/alpha/michelson.rst
@@ -2339,6 +2339,20 @@ Operations on timelock
    ::  chest_key : chest : nat : 'S -> or bytes bool : 'S
 
 
+Events
+~~~~~~
+
+- ``EMIT %tag 'ty``: constructs an operation that will write an event into
+  the transaction receipt after the successful execution of this contract.
+  It accepts as arguments an annotation as a tag to the emitted event and
+  the type of data attachment.
+
+  See :doc:`Event <event>` for more information.
+
+::
+    
+    :: 'ty : 'S -> operation : 'S
+
 
 Removed instructions
 ~~~~~~~~~~~~~~~~~~~~
diff --git a/docs/alpha/protocol.rst b/docs/alpha/protocol.rst
index 30430754cfe5b56a6d8baae5853676bb902d27f4..05ac61a2d07057b623a6972bd108917176e7654b 100644
--- a/docs/alpha/protocol.rst
+++ b/docs/alpha/protocol.rst
@@ -75,3 +75,8 @@ Sapling, etc), and some details about its implementation.
    :maxdepth: 2
 
    plugins
+
+.. toctree::
+   :maxdepth: 2
+   
+   event
diff --git a/docs/protocols/alpha.rst b/docs/protocols/alpha.rst
index 0e1a1219c16670ded21806a3c221e2799443360d..65a67939f20f34eedcfa550849496f1bb314cf82 100644
--- a/docs/protocols/alpha.rst
+++ b/docs/protocols/alpha.rst
@@ -17,6 +17,18 @@ Smart Contract Optimistic Rollups
 
 Rollups supporting execution of smart contracts. (MRs :gl:`!4933`, :gl:`!4812`)
 
+Contract Event Logging
+----------------------
+
+Contracts may now emit events thanks to a new ``EMIT`` instruction.
+
+Event emissions are denoted by internal operations that perform a contract call to a specific class of addresses starting with `ev1`. 
+
+This new class of addresses can be computed with a newly introduced RPC at ``helpers/scripts/event_address``.
+
+See :doc:`Event <../alpha/event>` for more information.
+(MR :gl:`!4656`)
+
 Breaking Changes
 ----------------
 
diff --git a/src/proto_alpha/lib_benchmarks_proto/interpreter_model.ml b/src/proto_alpha/lib_benchmarks_proto/interpreter_model.ml
index 4754e9766a3cdb166181ed6a38a3a838b413d3f5..10224dc78f35eba7d437ad41e3d6cf2de12c5bdb 100644
--- a/src/proto_alpha/lib_benchmarks_proto/interpreter_model.ml
+++ b/src/proto_alpha/lib_benchmarks_proto/interpreter_model.ml
@@ -454,7 +454,8 @@ let ir_model ?specialization instr_or_cont =
       | N_IHalt -> model_0 instr_or_cont (const1_model name)
       | N_IApply -> model_0 instr_or_cont (const1_model name)
       | N_ILog -> model_0 instr_or_cont (const1_model name)
-      | N_IOpen_chest -> model_2 instr_or_cont (open_chest_model name))
+      | N_IOpen_chest -> model_2 instr_or_cont (open_chest_model name)
+      | N_IEmit -> model_0 instr_or_cont (const1_model name))
   | Cont_name cont -> (
       match cont with
       | N_KNil -> model_0 instr_or_cont (const1_model name)
diff --git a/src/proto_alpha/lib_benchmarks_proto/interpreter_workload.ml b/src/proto_alpha/lib_benchmarks_proto/interpreter_workload.ml
index db53a2d2e1aa24987bd76741f469a723e3975e1e..ad3a114d248fa755520f129f6095a00cc253dfeb 100644
--- a/src/proto_alpha/lib_benchmarks_proto/interpreter_workload.ml
+++ b/src/proto_alpha/lib_benchmarks_proto/interpreter_workload.ml
@@ -223,6 +223,8 @@ type instruction_name =
   | N_ILog
   (* Timelock*)
   | N_IOpen_chest
+  (* Event *)
+  | N_IEmit
 
 type continuation_name =
   | N_KNil
@@ -408,6 +410,7 @@ let string_of_instruction_name : instruction_name -> string =
   | N_IHalt -> "N_IHalt"
   | N_ILog -> "N_ILog"
   | N_IOpen_chest -> "N_IOpen_chest"
+  | N_IEmit -> "N_IEmit"
 
 let string_of_continuation_name : continuation_name -> string =
  fun c ->
@@ -628,6 +631,7 @@ let all_instructions =
     N_IHalt;
     N_ILog;
     N_IOpen_chest;
+    N_IEmit;
   ]
 
 let all_continuations =
@@ -1093,6 +1097,9 @@ module Instructions = struct
 
   let open_chest log_time size =
     ir_sized_step N_IOpen_chest (binary "log_time" log_time "size" size)
+
+  (** cost model for the EMIT instruction *)
+  let emit = ir_sized_step N_IEmit nullary
 end
 
 module Control = struct
@@ -1425,6 +1432,7 @@ let extract_ir_sized_step :
       let log_time = Z.log2 Z.(one + Script_int.to_zint time) |> Size.of_int in
       Instructions.open_chest log_time plaintext_size
   | IMin_block_time _, _ -> Instructions.min_block_time
+  | IEmit _, _ -> Instructions.emit
 
 let extract_control_trace (type bef_top bef aft_top aft)
     (cont : (bef_top, bef, aft_top, aft) Script_typed_ir.continuation) =
diff --git a/src/proto_alpha/lib_client/client_proto_programs.ml b/src/proto_alpha/lib_client/client_proto_programs.ml
index e2e7d31e3803719f9df725ee37a1a49f05879354..73b4710ffb9552da22dbb64e51e609f594626266 100644
--- a/src/proto_alpha/lib_client/client_proto_programs.ml
+++ b/src/proto_alpha/lib_client/client_proto_programs.ml
@@ -388,3 +388,7 @@ let print_unreachables (cctxt : #Client_context.printer) ~emacs ?script_name
     ?script_name
     ~on_errors:(print_errors cctxt ~show_source ~parsed)
     ty
+
+let get_event_address cctxt ~chain ~block ~ty =
+  Plugin.RPC.Scripts.get_event_address cctxt (chain, block) ~ty
+  >>=? fun address -> return address
diff --git a/src/proto_alpha/lib_client/client_proto_programs.mli b/src/proto_alpha/lib_client/client_proto_programs.mli
index dd6f3ff3353079e3de0ce70b6995418950c8a0b6..f1a783c79c15772a8c95248a8b15143afef87bae 100644
--- a/src/proto_alpha/lib_client/client_proto_programs.mli
+++ b/src/proto_alpha/lib_client/client_proto_programs.mli
@@ -224,3 +224,12 @@ val print_unreachables :
   parsed:Michelson_v1_parser.parsed ->
   Michelson_v1_primitives.prim list list tzresult ->
   unit tzresult Lwt.t
+
+(** A service implementation to compute the event address
+    for a given event tag and a Michelson event type definition *)
+val get_event_address :
+  #Protocol_client_context.rpc_context ->
+  chain:Chain_services.chain ->
+  block:Block_services.block ->
+  ty:Alpha_context.Script.expr ->
+  Alpha_context.Contract_event.t tzresult Lwt.t
diff --git a/src/proto_alpha/lib_client/injection.ml b/src/proto_alpha/lib_client/injection.ml
index d0a1fd86f59f4395d11a27e73df3ba24fc10a214..7942dbfacb5d3e3ad4143ed10408c88a1a97690b 100644
--- a/src/proto_alpha/lib_client/injection.ml
+++ b/src/proto_alpha/lib_client/injection.ml
@@ -310,7 +310,8 @@ let estimated_gas_single (type kind)
         | Transaction_result
             ( Transaction_to_contract_result {consumed_gas; _}
             | Transaction_to_tx_rollup_result {consumed_gas; _}
-            | Transaction_to_sc_rollup_result {consumed_gas; _} ) ->
+            | Transaction_to_sc_rollup_result {consumed_gas; _}
+            | Transaction_to_event_result {consumed_gas; _} ) ->
             Ok consumed_gas
         | Origination_result {consumed_gas; _} -> Ok consumed_gas
         | Reveal_result {consumed_gas} -> Ok consumed_gas
@@ -350,7 +351,8 @@ let estimated_gas_single (type kind)
         | ITransaction_result
             ( Transaction_to_contract_result {consumed_gas; _}
             | Transaction_to_tx_rollup_result {consumed_gas; _}
-            | Transaction_to_sc_rollup_result {consumed_gas; _} ) ->
+            | Transaction_to_sc_rollup_result {consumed_gas; _}
+            | Transaction_to_event_result {consumed_gas; _} ) ->
             Ok consumed_gas
         | IOrigination_result {consumed_gas; _} -> Ok consumed_gas
         | IDelegation_result {consumed_gas} -> Ok consumed_gas)
@@ -385,7 +387,10 @@ let estimated_storage_single (type kind) ~tx_rollup_origination_size
                We need to charge for newly allocated storage (as we do for
                Michelson’s big map). *)
             Ok Z.zero
-        | Transaction_result (Transaction_to_sc_rollup_result _) -> Ok Z.zero
+        | Transaction_result
+            (Transaction_to_sc_rollup_result _ | Transaction_to_event_result _)
+          ->
+            Ok Z.zero
         | Origination_result {paid_storage_size_diff; _} ->
             Ok (Z.add paid_storage_size_diff origination_size)
         | Reveal_result _ -> Ok Z.zero
@@ -441,7 +446,10 @@ let estimated_storage_single (type kind) ~tx_rollup_origination_size
                We need to charge for newly allocated storage (as we do for
                Michelson’s big map). *)
             Ok Z.zero
-        | ITransaction_result (Transaction_to_sc_rollup_result _) -> Ok Z.zero
+        | ITransaction_result
+            (Transaction_to_sc_rollup_result _ | Transaction_to_event_result _)
+          ->
+            Ok Z.zero
         | IOrigination_result {paid_storage_size_diff; _} ->
             Ok (Z.add paid_storage_size_diff origination_size)
         | IDelegation_result _ -> Ok Z.zero)
@@ -488,7 +496,8 @@ let originated_contracts_single (type kind)
             Ok originated_contracts
         | Transaction_result
             ( Transaction_to_tx_rollup_result _
-            | Transaction_to_sc_rollup_result _ ) ->
+            | Transaction_to_sc_rollup_result _ | Transaction_to_event_result _
+              ) ->
             Ok []
         | Origination_result {originated_contracts; _} ->
             Ok originated_contracts
@@ -527,7 +536,8 @@ let originated_contracts_single (type kind)
             Ok originated_contracts
         | ITransaction_result
             ( Transaction_to_tx_rollup_result _
-            | Transaction_to_sc_rollup_result _ ) ->
+            | Transaction_to_sc_rollup_result _ | Transaction_to_event_result _
+              ) ->
             Ok []
         | IOrigination_result {originated_contracts; _} ->
             Ok originated_contracts
diff --git a/src/proto_alpha/lib_client/operation_result.ml b/src/proto_alpha/lib_client/operation_result.ml
index 30404d93707b1685a5f942a95280298fee8d4c03..d156bd67bc800eb5563654104a4e2d1885d07ace 100644
--- a/src/proto_alpha/lib_client/operation_result.ml
+++ b/src/proto_alpha/lib_client/operation_result.ml
@@ -533,6 +533,9 @@ let pp_transaction_result ppf = function
   | Transaction_to_sc_rollup_result {consumed_gas; inbox_after} ->
       pp_consumed_gas ppf consumed_gas ;
       pp_inbox_after ppf inbox_after
+  | Transaction_to_event_result {consumed_gas} ->
+      pp_consumed_gas ppf consumed_gas ;
+      Format.fprintf ppf "@,@[<v 2>Event Applied]"
 
 let pp_operation_result ~operation_name pp_operation_result ppf = function
   | Skipped _ -> Format.fprintf ppf "This operation was skipped."
diff --git a/src/proto_alpha/lib_client_commands/client_proto_programs_commands.ml b/src/proto_alpha/lib_client_commands/client_proto_programs_commands.ml
index d82c6be1bc6c8e9a372a055057149908d1129358..1f12d3a964e87cf04e465c71c27b0ed2ee75b5c5 100644
--- a/src/proto_alpha/lib_client_commands/client_proto_programs_commands.ml
+++ b/src/proto_alpha/lib_client_commands/client_proto_programs_commands.ml
@@ -1049,4 +1049,23 @@ let commands () =
             unlimited_gas;
           }
         >>= fun res -> print_view_result cctxt res);
+    command
+      ~group
+      ~desc:"Compute the event address associated with a tag and a data type."
+      no_options
+      (prefixes ["get"; "event"; "address"]
+      @@ param ~name:"type" ~desc:"the type of the event data" data_parameter
+      @@ stop)
+      (fun () ty cctxt ->
+        Client_proto_programs.get_event_address
+          cctxt
+          ~chain:cctxt#chain
+          ~block:cctxt#block
+          ~ty:ty.expanded
+        >>=? fun addr ->
+        cctxt#message
+          "@[<v 2>Event address: @,%a@]@."
+          Contract_event_repr.pp
+          addr
+        >|= ok);
   ]
diff --git a/src/proto_alpha/lib_plugin/RPC.ml b/src/proto_alpha/lib_plugin/RPC.ml
index 86144e9985b5f9cee56b6ea14c9860b97e7361d8..f45fb752462d11914f03109bbb94eaf5b26aba52 100644
--- a/src/proto_alpha/lib_plugin/RPC.ml
+++ b/src/proto_alpha/lib_plugin/RPC.ml
@@ -459,6 +459,16 @@ module Scripts = struct
                 [])
              (req "entrypoints" (assoc Script.expr_encoding)))
         RPC_path.(path / "entrypoints")
+
+    (** [get_event_address] is a RPC service to compute the contract event address
+        for the input tag and Michelson event type definition. *)
+    let get_event_address =
+      RPC_service.post_service
+        ~description:"Return the event address for the given tag and data type"
+        ~input:(obj1 (req "type" Script.expr_encoding))
+        ~output:(obj1 (req "address" Contract_event.Hash.encoding))
+        ~query:RPC_query.empty
+        RPC_path.(path / "event_address")
   end
 
   module type UNPARSING_MODE = sig
@@ -805,6 +815,7 @@ module Scripts = struct
       | ISplit_ticket _ -> pp_print_string fmt "SPLIT_TICKET"
       | IJoin_tickets _ -> pp_print_string fmt "JOIN_TICKETS"
       | IOpen_chest _ -> pp_print_string fmt "OPEN_CHEST"
+      | IEmit _ -> pp_print_string fmt "EMIT"
       | IHalt _ -> pp_print_string fmt "[halt]"
       | ILog (_, _, _, _, instr) ->
           Format.fprintf fmt "log/%a" pp_instr_name instr
@@ -1492,7 +1503,14 @@ module Scripts = struct
                     Micheline.strip_locations original_type_expr )
                   :: acc)
                 map
-                [] ) ))
+                [] ) )) ;
+    Registration.register0
+      ~chunked:false
+      S.get_event_address
+      (fun ctxt () ty_node ->
+        let ctxt = Gas.set_unlimited ctxt in
+        Script_ir_translator.hash_event_ty ctxt (Micheline.root ty_node)
+        >>?= fun (address, _) -> return address)
 
   let run_code ?unparsing_mode ?gas ?(entrypoint = Entrypoint.default) ?balance
       ~script ~storage ~input ~amount ~chain_id ~source ~payer ~self ~now ~level
@@ -1633,6 +1651,10 @@ module Scripts = struct
 
   let list_entrypoints ctxt block ~script =
     RPC_context.make_call0 S.list_entrypoints ctxt block () script
+
+  (** [get_event_address] makes a call to the service to compute an event address *)
+  let get_event_address ~ty ctxt block =
+    RPC_context.make_call0 S.get_event_address ctxt block () ty
 end
 
 module Contract = struct
diff --git a/src/proto_alpha/lib_protocol/TEZOS_PROTOCOL b/src/proto_alpha/lib_protocol/TEZOS_PROTOCOL
index f7e3ec286ce442057e2e5490e9f3248bf51969b0..76c88eff3a739b62579247397830cfee1bc7567d 100644
--- a/src/proto_alpha/lib_protocol/TEZOS_PROTOCOL
+++ b/src/proto_alpha/lib_protocol/TEZOS_PROTOCOL
@@ -58,6 +58,7 @@
         "Sc_rollup_commitment_repr",
         "Sc_rollup_proof_repr",
         "Sc_rollup_game_repr",
+        "Contract_event_repr",
         "Tx_rollup_level_repr",
         "Tx_rollup_l2_proof",
         "Tx_rollup_l2_address",
diff --git a/src/proto_alpha/lib_protocol/alpha_context.ml b/src/proto_alpha/lib_protocol/alpha_context.ml
index 4b2d226b898c7ad33cb210c7de64be8dc17eb1d4..40aeb1fdd6345dfa731c6fdaa5bdd23bdff44fa5 100644
--- a/src/proto_alpha/lib_protocol/alpha_context.ml
+++ b/src/proto_alpha/lib_protocol/alpha_context.ml
@@ -251,6 +251,8 @@ module Script = struct
     Gas.consume_from available_gas gas_cost
 end
 
+module Contract_event = Contract_event_repr
+
 module Level = struct
   include Level_repr
   include Level_storage
diff --git a/src/proto_alpha/lib_protocol/alpha_context.mli b/src/proto_alpha/lib_protocol/alpha_context.mli
index 76c8c35068bcc57087ef62b8850bf1ef2fb1d5ca..2047d1f6da02e5b63d14a27e06d2da358f389e49 100644
--- a/src/proto_alpha/lib_protocol/alpha_context.mli
+++ b/src/proto_alpha/lib_protocol/alpha_context.mli
@@ -634,6 +634,7 @@ module Script : sig
     | I_SPLIT_TICKET
     | I_JOIN_TICKETS
     | I_OPEN_CHEST
+    | I_EMIT
     | T_bool
     | T_contract
     | T_int
@@ -2291,6 +2292,19 @@ module Bond_id : sig
   end
 end
 
+(** Contract_event exposes fields for event data access. See [Contract_event_repr]. *)
+module Contract_event : sig
+  module Hash : module type of Contract_event_repr.Hash
+
+  type t = Hash.t
+
+  val in_memory_size : t -> Cache_memory_helpers.sint
+
+  val to_b58check : t -> string
+
+  val pp : Format.formatter -> t -> unit
+end
+
 (** This module re-exports definitions from {!Receipt_repr}. *)
 module Receipt : sig
   type balance =
@@ -3179,6 +3193,7 @@ module Destination : sig
     | Contract of Contract.t
     | Tx_rollup of Tx_rollup.t
     | Sc_rollup of Sc_rollup.t
+    | Event of Contract_event.t
 
   val encoding : t Data_encoding.t
 
diff --git a/src/proto_alpha/lib_protocol/apply.ml b/src/proto_alpha/lib_protocol/apply.ml
index 5c8f1820772236ae22c3ac1be124f50c6016e6f6..5478fc5d53b6d5f8dbe3eb4a451213984cbb6f2e 100644
--- a/src/proto_alpha/lib_protocol/apply.ml
+++ b/src/proto_alpha/lib_protocol/apply.ml
@@ -1188,6 +1188,13 @@ let apply_internal_manager_operation_content :
         Transaction_to_sc_rollup_result {consumed_gas; inbox_after}
       in
       (ctxt, ITransaction_result result, [])
+  | Transaction_to_event {addr = _; unparsed_data = _; tag = _} ->
+      return
+        ( ctxt,
+          ITransaction_result
+            (Transaction_to_event_result
+               {consumed_gas = Gas.consumed ~since:ctxt_before_op ~until:ctxt}),
+          [] )
   | Origination
       {
         delegate;
@@ -1954,6 +1961,8 @@ let burn_transaction_storage_fees ctxt trr ~storage_limit ~payer =
           storage_limit,
           Transaction_to_tx_rollup_result {payload with balance_updates} )
   | Transaction_to_sc_rollup_result _ -> return (ctxt, storage_limit, trr)
+  | Transaction_to_event_result {consumed_gas} ->
+      return (ctxt, storage_limit, Transaction_to_event_result {consumed_gas})
 
 let burn_origination_storage_fees ctxt
     {
diff --git a/src/proto_alpha/lib_protocol/apply_internal_results.ml b/src/proto_alpha/lib_protocol/apply_internal_results.ml
index cd2e0d6b182d781436700a581bfe8751a0c15bd2..2a4ddcf7d2e876ac192044257b5478f12d670d28 100644
--- a/src/proto_alpha/lib_protocol/apply_internal_results.ml
+++ b/src/proto_alpha/lib_protocol/apply_internal_results.ml
@@ -91,6 +91,14 @@ let contents_of_internal_operation (type kind)
             entrypoint;
             parameters = Script.lazy_expr unparsed_parameters;
           }
+    | Transaction_to_event {addr; tag; unparsed_data} ->
+        Transaction
+          {
+            destination = Event addr;
+            amount = Tez.zero;
+            entrypoint = tag;
+            parameters = Script.lazy_expr unparsed_data;
+          }
     | Origination {delegate; code; unparsed_storage; credit; _} ->
         let script =
           {
@@ -131,6 +139,7 @@ type successful_transaction_result =
       consumed_gas : Gas.Arith.fp;
       inbox_after : Sc_rollup.Inbox.t;
     }
+  | Transaction_to_event_result of {consumed_gas : Gas.Arith.fp}
 
 type successful_origination_result = {
   lazy_storage_diff : Lazy_storage.diffs option;
@@ -300,6 +309,15 @@ module Internal_result = struct
           (function
             | consumed_gas, inbox_after ->
                 Transaction_to_sc_rollup_result {consumed_gas; inbox_after});
+        case
+          ~title:"To_event"
+          (Tag 3)
+          (obj1
+             (dft "consumed_milligas" Gas.Arith.n_fp_encoding Gas.Arith.zero))
+          (function
+            | Transaction_to_event_result {consumed_gas} -> Some consumed_gas
+            | _ -> None)
+          (fun consumed_gas -> Transaction_to_event_result {consumed_gas});
       ]
 
   let[@coq_axiom_with_reason "gadt"] transaction_case =
diff --git a/src/proto_alpha/lib_protocol/apply_internal_results.mli b/src/proto_alpha/lib_protocol/apply_internal_results.mli
index 470a5ce207eaabd3cc17f863bb6df76f0d0554e6..2404113297bffcd3ad92b977b79f2b85880055c2 100644
--- a/src/proto_alpha/lib_protocol/apply_internal_results.mli
+++ b/src/proto_alpha/lib_protocol/apply_internal_results.mli
@@ -86,6 +86,7 @@ type successful_transaction_result =
       consumed_gas : Gas.Arith.fp;
       inbox_after : Sc_rollup.Inbox.t;
     }
+  | Transaction_to_event_result of {consumed_gas : Gas.Arith.fp}
 
 (** Result of applying an internal origination. *)
 type successful_origination_result = {
diff --git a/src/proto_alpha/lib_protocol/apply_results.ml b/src/proto_alpha/lib_protocol/apply_results.ml
index bb7fc7e85ca87e733572cacd90050bb594610b18..42e4072b1e068e50859c3fb1b74f6b4d0ea33670 100644
--- a/src/proto_alpha/lib_protocol/apply_results.ml
+++ b/src/proto_alpha/lib_protocol/apply_results.ml
@@ -383,6 +383,15 @@ module Manager_result = struct
           (function
             | consumed_gas, inbox_after ->
                 Transaction_to_sc_rollup_result {consumed_gas; inbox_after});
+        case
+          ~title:"To_event"
+          (Tag 3)
+          (obj1
+             (dft "consumed_milligas" Gas.Arith.n_fp_encoding Gas.Arith.zero))
+          (function
+            | Transaction_to_event_result {consumed_gas} -> Some consumed_gas
+            | _ -> None)
+          (fun consumed_gas -> Transaction_to_event_result {consumed_gas});
       ]
 
   let[@coq_axiom_with_reason "gadt"] transaction_case =
diff --git a/src/proto_alpha/lib_protocol/contract_event_repr.ml b/src/proto_alpha/lib_protocol/contract_event_repr.ml
new file mode 100644
index 0000000000000000000000000000000000000000..639f4c01ede04d5abbb06f9a637c629a737e62e0
--- /dev/null
+++ b/src/proto_alpha/lib_protocol/contract_event_repr.ml
@@ -0,0 +1,68 @@
+(*****************************************************************************)
+(*                                                                           *)
+(* Open Source License                                                       *)
+(* Copyright (c) 2022 Marigold <contact@marigold.dev>                        *)
+(*                                                                           *)
+(* 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.                                                 *)
+(*                                                                           *)
+(*****************************************************************************)
+
+type error += (* `Permanent *) Invalid_event_notation of string
+
+module Hash = struct
+  let prefix = "\058\017\082" (* "ev1" (32) *)
+
+  module H =
+    Blake2B.Make
+      (Base58)
+      (struct
+        let name = "Event"
+
+        let title = "Event sink"
+
+        let b58check_prefix = prefix
+
+        let size = None
+      end)
+
+  include H
+
+  let () = Base58.check_encoded_prefix b58check_encoding "ev1" 53
+
+  include Path_encoding.Make_hex (H)
+end
+
+type t = Hash.t
+
+let of_b58data = function Hash.Data hash -> Some hash | _ -> None
+
+let pp = Hash.pp
+
+let of_b58check_opt s = Option.bind (Base58.decode s) of_b58data
+
+let of_b58check s =
+  match of_b58check_opt s with
+  | Some hash -> ok hash
+  | None -> error (Invalid_event_notation s)
+
+let to_b58check hash = Hash.to_b58check hash
+
+let in_memory_size _ =
+  let open Cache_memory_helpers in
+  h1w +! string_size_gen Hash.size
diff --git a/src/proto_alpha/lib_protocol/contract_event_repr.mli b/src/proto_alpha/lib_protocol/contract_event_repr.mli
new file mode 100644
index 0000000000000000000000000000000000000000..adeeff40a82955255a174499f6966cbabe23f2d0
--- /dev/null
+++ b/src/proto_alpha/lib_protocol/contract_event_repr.mli
@@ -0,0 +1,54 @@
+(*****************************************************************************)
+(*                                                                           *)
+(* Open Source License                                                       *)
+(* Copyright (c) 2022 Marigold <contact@marigold.dev>                        *)
+(*                                                                           *)
+(* 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 Hash : sig
+  val prefix : string
+
+  include S.HASH
+end
+
+type t = Hash.t
+
+(** [in_memory_size event_addr] returns the number of bytes [event_addr]
+    uses in RAM. *)
+val in_memory_size : t -> Cache_memory_helpers.sint
+
+(** [to_b58check addr] converts the event address [addr] to the Base58Check string representation *)
+val to_b58check : t -> string
+
+(** Pretty printer for contract events *)
+val pp : Format.formatter -> t -> unit
+
+(** [of_b58data data] tries to decode a contract event from a Base58 [data] and
+    return [None] if conversion fails *)
+val of_b58data : Base58.data -> t option
+
+(** [of_b58check addr] tries to decode a contract event from a Base58Check string [addr] *)
+val of_b58check : string -> t tzresult
+
+(** [of_b58check_opt addr] tries to
+    decode a contract event from a Base58Check string [addr]
+    and return [None] if conversion fails *)
+val of_b58check_opt : string -> t option
diff --git a/src/proto_alpha/lib_protocol/destination_repr.ml b/src/proto_alpha/lib_protocol/destination_repr.ml
index 638fcfe83b3c573ee1ea084341de4a0a4cf835f1..93cb5c141a477033d13f6fce73e1c94ef7d261df 100644
--- a/src/proto_alpha/lib_protocol/destination_repr.ml
+++ b/src/proto_alpha/lib_protocol/destination_repr.ml
@@ -29,6 +29,7 @@ type t =
   | Contract of Contract_repr.t
   | Tx_rollup of Tx_rollup_repr.t
   | Sc_rollup of Sc_rollup_repr.t
+  | Event of Contract_event_repr.t
 (* If you add more cases to this type, please update the
    [test_compare_destination] test in
    [test/unit/test_destination_repr.ml] to ensure that the compare
@@ -43,6 +44,7 @@ include Compare.Make (struct
     | Contract k1, Contract k2 -> Contract_repr.compare k1 k2
     | Tx_rollup k1, Tx_rollup k2 -> Tx_rollup_repr.compare k1 k2
     | Sc_rollup k1, Sc_rollup k2 -> Sc_rollup_repr.Address.compare k1 k2
+    | Event k1, Event k2 -> Contract_event_repr.Hash.compare k1 k2
     (* This function is used by the Michelson interpreter to compare
        addresses. It is of significant importance to remember that in
        Michelson, address comparison is used to distinguish between
@@ -52,14 +54,17 @@ include Compare.Make (struct
        modified when new constructors are added to [t]. *)
     | Contract _, _ -> -1
     | _, Contract _ -> 1
-    | Tx_rollup _, Sc_rollup _ -> -1
-    | Sc_rollup _, Tx_rollup _ -> 1
+    | Tx_rollup _, _ -> -1
+    | _, Tx_rollup _ -> 1
+    | Sc_rollup _, _ -> -1
+    | _, Sc_rollup _ -> 1
 end)
 
 let to_b58check = function
   | Contract k -> Contract_repr.to_b58check k
   | Tx_rollup k -> Tx_rollup_repr.to_b58check k
   | Sc_rollup k -> Sc_rollup_repr.Address.to_b58check k
+  | Event k -> Contract_event_repr.to_b58check k
 
 type error += Invalid_destination_b58check of string
 
@@ -81,9 +86,12 @@ let of_b58data data =
   | None -> (
       match Tx_rollup_repr.of_b58data data with
       | Some tx_rollup -> Some (Tx_rollup tx_rollup)
-      | None ->
-          Sc_rollup_repr.Address.of_b58data data
-          |> Option.map (fun sc_rollup -> Sc_rollup sc_rollup))
+      | None -> (
+          match Sc_rollup_repr.Address.of_b58data data with
+          | Some sc_rollup -> Some (Sc_rollup sc_rollup)
+          | None ->
+              Contract_event_repr.of_b58data data
+              |> Option.map (fun c -> Event c)))
 
 let of_b58check_opt s = Option.bind (Base58.decode s) of_b58data
 
@@ -122,6 +130,12 @@ let encoding =
                   ~title:"Sc_rollup"
                   (function Sc_rollup k -> Some k | _ -> None)
                   (fun k -> Sc_rollup k);
+                case
+                  (Tag 4)
+                  (Fixed.add_padding Contract_event_repr.Hash.encoding 1)
+                  ~title:"Event sink"
+                  (function Event k -> Some k | _ -> None)
+                  (fun k -> Event k);
               ]))
        ~json:
          (conv
@@ -139,6 +153,7 @@ let pp : Format.formatter -> t -> unit =
   | Contract k -> Contract_repr.pp fmt k
   | Tx_rollup k -> Tx_rollup_repr.pp fmt k
   | Sc_rollup k -> Sc_rollup_repr.pp fmt k
+  | Event k -> Contract_event_repr.pp fmt k
 
 let in_memory_size =
   let open Cache_memory_helpers in
@@ -146,3 +161,4 @@ let in_memory_size =
   | Contract k -> h1w +! Contract_repr.in_memory_size k
   | Tx_rollup k -> h1w +! Tx_rollup_repr.in_memory_size k
   | Sc_rollup k -> h1w +! Sc_rollup_repr.in_memory_size k
+  | Event k -> h1w +! Contract_event_repr.in_memory_size k
diff --git a/src/proto_alpha/lib_protocol/destination_repr.mli b/src/proto_alpha/lib_protocol/destination_repr.mli
index 2b0c3e57f0c58d1cc48db08b5d0718367c28badc..e884a16f6a0dcdc1dac9735fa61e8dc2a54a1d42 100644
--- a/src/proto_alpha/lib_protocol/destination_repr.mli
+++ b/src/proto_alpha/lib_protocol/destination_repr.mli
@@ -45,6 +45,7 @@ type t =
   | Contract of Contract_repr.t
   | Tx_rollup of Tx_rollup_repr.t
   | Sc_rollup of Sc_rollup_repr.t
+  | Event of Contract_event_repr.t
 
 include Compare.S with type t := t
 
diff --git a/src/proto_alpha/lib_protocol/dune b/src/proto_alpha/lib_protocol/dune
index d59b58f04d031589509965603ff79ff5b236f0ff..4894fb33af17c523972ca7417264aa24c10b5782 100644
--- a/src/proto_alpha/lib_protocol/dune
+++ b/src/proto_alpha/lib_protocol/dune
@@ -87,6 +87,7 @@
   Sc_rollup_commitment_repr
   Sc_rollup_proof_repr
   Sc_rollup_game_repr
+  Contract_event_repr
   Tx_rollup_level_repr
   Tx_rollup_l2_proof
   Tx_rollup_l2_address
@@ -312,6 +313,7 @@
   sc_rollup_commitment_repr.ml sc_rollup_commitment_repr.mli
   sc_rollup_proof_repr.ml sc_rollup_proof_repr.mli
   sc_rollup_game_repr.ml sc_rollup_game_repr.mli
+  contract_event_repr.ml contract_event_repr.mli
   tx_rollup_level_repr.ml tx_rollup_level_repr.mli
   tx_rollup_l2_proof.ml tx_rollup_l2_proof.mli
   tx_rollup_l2_address.ml tx_rollup_l2_address.mli
@@ -524,6 +526,7 @@
   sc_rollup_commitment_repr.ml sc_rollup_commitment_repr.mli
   sc_rollup_proof_repr.ml sc_rollup_proof_repr.mli
   sc_rollup_game_repr.ml sc_rollup_game_repr.mli
+  contract_event_repr.ml contract_event_repr.mli
   tx_rollup_level_repr.ml tx_rollup_level_repr.mli
   tx_rollup_l2_proof.ml tx_rollup_l2_proof.mli
   tx_rollup_l2_address.ml tx_rollup_l2_address.mli
@@ -745,6 +748,7 @@
   sc_rollup_commitment_repr.ml sc_rollup_commitment_repr.mli
   sc_rollup_proof_repr.ml sc_rollup_proof_repr.mli
   sc_rollup_game_repr.ml sc_rollup_game_repr.mli
+  contract_event_repr.ml contract_event_repr.mli
   tx_rollup_level_repr.ml tx_rollup_level_repr.mli
   tx_rollup_l2_proof.ml tx_rollup_l2_proof.mli
   tx_rollup_l2_address.ml tx_rollup_l2_address.mli
@@ -970,6 +974,7 @@
   sc_rollup_commitment_repr.ml sc_rollup_commitment_repr.mli
   sc_rollup_proof_repr.ml sc_rollup_proof_repr.mli
   sc_rollup_game_repr.ml sc_rollup_game_repr.mli
+  contract_event_repr.ml contract_event_repr.mli
   tx_rollup_level_repr.ml tx_rollup_level_repr.mli
   tx_rollup_l2_proof.ml tx_rollup_l2_proof.mli
   tx_rollup_l2_address.ml tx_rollup_l2_address.mli
diff --git a/src/proto_alpha/lib_protocol/michelson_v1_gas.ml b/src/proto_alpha/lib_protocol/michelson_v1_gas.ml
index 39f89d88f157c7f33da62fbd0127fcce6a0465cb..497072da66705b89a5e00a69f30101c6cda62e2a 100644
--- a/src/proto_alpha/lib_protocol/michelson_v1_gas.ml
+++ b/src/proto_alpha/lib_protocol/michelson_v1_gas.ml
@@ -962,6 +962,9 @@ module Cost_of = struct
     (* model SAPLING_DIFF_ENCODING *)
     let cost_SAPLING_DIFF_ENCODING ~nfs ~cms =
       S.safe_int ((nfs * 22) + (cms * 215))
+
+    (* model IEmit *)
+    let cost_N_IEmit = S.safe_int 30
   end
 
   module Interpreter = struct
@@ -1508,6 +1511,8 @@ module Cost_of = struct
         contents_comparison +@ compare_address
         +@ add_nat ticket_a.amount ticket_b.amount)
 
+    let emit = atomic_step_cost cost_N_IEmit
+
     (* Continuations *)
     module Control = struct
       let nil = atomic_step_cost cost_N_KNil
diff --git a/src/proto_alpha/lib_protocol/michelson_v1_gas.mli b/src/proto_alpha/lib_protocol/michelson_v1_gas.mli
index c87e1a14a64ac4280cec130bb28bec8a28fa0586..b91b3cd478386a857aced7aa37f620b5b143c024 100644
--- a/src/proto_alpha/lib_protocol/michelson_v1_gas.mli
+++ b/src/proto_alpha/lib_protocol/michelson_v1_gas.mli
@@ -362,6 +362,9 @@ module Cost_of : sig
     val open_chest :
       chest:Script_typed_ir.Script_timelock.chest -> time:Z.t -> Gas.cost
 
+    (** cost to generate one event emission internal operation *)
+    val emit : Gas.cost
+
     module Control : sig
       val nil : Gas.cost
 
diff --git a/src/proto_alpha/lib_protocol/michelson_v1_primitives.ml b/src/proto_alpha/lib_protocol/michelson_v1_primitives.ml
index 97464d4f6aee189eb4c926f11445fd62a48348c1..abbad29046c1dae6433d9fa3e6f53aa9006f2fcc 100644
--- a/src/proto_alpha/lib_protocol/michelson_v1_primitives.ml
+++ b/src/proto_alpha/lib_protocol/michelson_v1_primitives.ml
@@ -151,6 +151,7 @@ type prim =
   | I_SPLIT_TICKET
   | I_JOIN_TICKETS
   | I_OPEN_CHEST
+  | I_EMIT
   | T_bool
   | T_contract
   | T_int
@@ -216,7 +217,8 @@ let namespace = function
   | I_SENDER | I_SET_DELEGATE | I_SHA256 | I_SHA512 | I_SHA3 | I_SIZE | I_SLICE
   | I_SOME | I_SOURCE | I_SPLIT_TICKET | I_STEPS_TO_QUOTA | I_SUB | I_SUB_MUTEZ
   | I_SWAP | I_TICKET | I_TOTAL_VOTING_POWER | I_TRANSFER_TOKENS | I_UNIT
-  | I_UNPACK | I_UNPAIR | I_UPDATE | I_VOTING_POWER | I_XOR | I_OPEN_CHEST ->
+  | I_UNPACK | I_UNPAIR | I_UPDATE | I_VOTING_POWER | I_XOR | I_OPEN_CHEST
+  | I_EMIT ->
       Instr_namespace
   | T_address | T_tx_rollup_l2_address | T_big_map | T_bool | T_bytes
   | T_chain_id | T_contract | T_int | T_key | T_key_hash | T_lambda | T_list
@@ -357,6 +359,7 @@ let string_of_prim = function
   | I_SPLIT_TICKET -> "SPLIT_TICKET"
   | I_JOIN_TICKETS -> "JOIN_TICKETS"
   | I_OPEN_CHEST -> "OPEN_CHEST"
+  | I_EMIT -> "EMIT"
   | I_VIEW -> "VIEW"
   | T_bool -> "bool"
   | T_contract -> "contract"
@@ -511,6 +514,7 @@ let prim_of_string = function
   | "SPLIT_TICKET" -> ok I_SPLIT_TICKET
   | "JOIN_TICKETS" -> ok I_JOIN_TICKETS
   | "OPEN_CHEST" -> ok I_OPEN_CHEST
+  | "EMIT" -> ok I_EMIT
   | "bool" -> ok T_bool
   | "contract" -> ok T_contract
   | "int" -> ok T_int
@@ -760,7 +764,10 @@ let prim_encoding =
          (* Alpha_013 addition *)
          ("tx_rollup_l2_address", T_tx_rollup_l2_address);
          ("MIN_BLOCK_TIME", I_MIN_BLOCK_TIME);
-         ("sapling_transaction", T_sapling_transaction)
+         ("sapling_transaction", T_sapling_transaction);
+         (* /!\ NEW INSTRUCTIONS MUST BE ADDED AT THE END OF THE STRING_ENUM, FOR BACKWARD COMPATIBILITY OF THE ENCODING. *)
+         (* Alpha_014 addition *)
+         ("EMIT", I_EMIT)
          (* New instructions must be added here, for backward compatibility of the encoding. *)
          (* Keep the comment above at the end of the list *);
        ]
diff --git a/src/proto_alpha/lib_protocol/michelson_v1_primitives.mli b/src/proto_alpha/lib_protocol/michelson_v1_primitives.mli
index 45f7ae7b0f94400061f5845fa4941236f77b1361..6d14592c1f7a0778f128aa89f24bea05a9bf76b7 100644
--- a/src/proto_alpha/lib_protocol/michelson_v1_primitives.mli
+++ b/src/proto_alpha/lib_protocol/michelson_v1_primitives.mli
@@ -164,6 +164,7 @@ type prim =
   | I_SPLIT_TICKET
   | I_JOIN_TICKETS
   | I_OPEN_CHEST
+  | I_EMIT
   | T_bool
   | T_contract
   | T_int
diff --git a/src/proto_alpha/lib_protocol/script_interpreter.ml b/src/proto_alpha/lib_protocol/script_interpreter.ml
index ec6d0b45437038a17acf3bd009b55ef30914fa17..75f62824c613e58c7cd4d10ea3fa9993bbd8590f 100644
--- a/src/proto_alpha/lib_protocol/script_interpreter.ml
+++ b/src/proto_alpha/lib_protocol/script_interpreter.ml
@@ -514,7 +514,7 @@ and iview : type a b c d e f i o. (a, b, c, d, e, f, i, o) iview_type =
     (step [@ocaml.tailcall]) (ctxt, sc) gas k ks None stack
   in
   match addr.destination with
-  | Contract (Implicit _) | Tx_rollup _ | Sc_rollup _ ->
+  | Contract (Implicit _) | Tx_rollup _ | Sc_rollup _ | Event _ ->
       (return_none [@ocaml.tailcall]) ctxt
   | Contract (Originated contract_hash as c) -> (
       Contract.get_script ctxt contract_hash >>=? fun (ctxt, script_opt) ->
@@ -1531,7 +1531,12 @@ and step : type a s b t r f. (a, s, b, t, r, f) step_type =
                 | Bogus_cipher -> R false
                 | Bogus_opening -> R true)
           in
-          (step [@ocaml.tailcall]) g gas k ks accu stack)
+          (step [@ocaml.tailcall]) g gas k ks accu stack
+      | IEmit {tag; ty = event_type; k; addr = event_address; loc = _} ->
+          let event_data = accu in
+          emit_event (ctxt, sc) gas ~event_address ~event_type ~tag ~event_data
+          >>=? fun (accu, ctxt, gas) ->
+          (step [@ocaml.tailcall]) (ctxt, sc) gas k ks accu stack)
 
 (*
 
diff --git a/src/proto_alpha/lib_protocol/script_interpreter.mli b/src/proto_alpha/lib_protocol/script_interpreter.mli
index 3d25819227559a5f42bb0e6aea6d54b9b41264ac..797a02f17f824d551ded98d018a0e0f2bf4a0f75 100644
--- a/src/proto_alpha/lib_protocol/script_interpreter.mli
+++ b/src/proto_alpha/lib_protocol/script_interpreter.mli
@@ -50,6 +50,7 @@ type error += Cannot_serialize_storage
 
 type error += Michelson_too_many_recursive_calls
 
+(** The result from script interpretation. *)
 type execution_result = {
   script : Script_ir_translator.ex_script;
   code_size : int;
diff --git a/src/proto_alpha/lib_protocol/script_interpreter_defs.ml b/src/proto_alpha/lib_protocol/script_interpreter_defs.ml
index 3b51e990b1d3a006ebf54c01e0b43f41f5f851a2..15655fe1757f30112d4bf3a1c1f025b4e88f2373 100644
--- a/src/proto_alpha/lib_protocol/script_interpreter_defs.ml
+++ b/src/proto_alpha/lib_protocol/script_interpreter_defs.ml
@@ -38,7 +38,7 @@ open Script_typed_ir
 open Script_ir_translator
 open Local_gas_counter
 
-type error += Rollup_invalid_transaction_amount
+type error += Rollup_invalid_transaction_amount | Event_invalid_destination
 
 let () =
   register_error_kind
@@ -53,7 +53,22 @@ let () =
       Format.pp_print_string ppf "Transaction amount to a rollup must be zero.")
     Data_encoding.unit
     (function Rollup_invalid_transaction_amount -> Some () | _ -> None)
-    (fun () -> Rollup_invalid_transaction_amount)
+    (fun () -> Rollup_invalid_transaction_amount) ;
+  register_error_kind
+    `Permanent
+    ~id:"operation.event_invalid_destination"
+    ~title:"Event sinks are invalid transaction destinations"
+    ~description:
+      "Event sinks are not real transaction destinations, and therefore \
+       operations targeting an event sink are invalid. To emit events, use \
+       EMIT instead."
+    ~pp:(fun ppf () ->
+      Format.pp_print_string
+        ppf
+        "Event sinks are invalid transaction destinations.")
+    Data_encoding.unit
+    (function Event_invalid_destination -> Some () | _ -> None)
+    (fun () -> Event_invalid_destination)
 
 (*
 
@@ -351,6 +366,7 @@ let cost_of_instr : type a s r f. (a, s, r, f) kinstr -> a -> s -> Gas.cost =
   | IOpen_chest _ ->
       let _chest_key = accu and chest, (time, _) = stack in
       Interp_costs.open_chest ~chest ~time:(Script_int.to_zint time)
+  | IEmit _ -> Interp_costs.emit
   | ILog _ -> Gas.free
  [@@ocaml.inline always]
  [@@coq_axiom_with_reason "unreachable expression `.` not handled"]
@@ -549,6 +565,26 @@ let make_transaction_to_sc_rollup ctxt ~destination ~amount ~entrypoint
           },
         ctxt ) )
 
+(** [emit_event] generates an internal operation that will effect an event emission
+    if the contract code returns this successfully. *)
+let emit_event (type t tc) (ctxt, sc) gas ~event_address
+    ~(event_type : (t, tc) ty) ~tag ~(event_data : t) =
+  let ctxt = update_context gas ctxt in
+  (* No need to take care of lazy storage as only packable types are allowed *)
+  let lazy_storage_diff = None in
+  unparse_data ctxt Optimized event_type event_data
+  >>=? fun (unparsed_data, ctxt) ->
+  Gas.consume ctxt (Script.strip_locations_cost unparsed_data) >>?= fun ctxt ->
+  let unparsed_data = Micheline.strip_locations unparsed_data in
+  fresh_internal_nonce ctxt >>?= fun (ctxt, nonce) ->
+  let operation =
+    Transaction_to_event {addr = event_address; tag; unparsed_data}
+  in
+  let iop = {source = Contract.Originated sc.self; operation; nonce} in
+  let res = {piop = Internal_operation iop; lazy_storage_diff} in
+  let gas, ctxt = local_gas_counter_and_outdated_context ctxt in
+  return (res, ctxt, gas)
+
 (* [transfer (ctxt, sc) gas tez parameters_ty parameters destination entrypoint]
    creates an operation that transfers an amount of [tez] to a destination and
    an entrypoint instantiated with argument [parameters] of type
@@ -593,7 +629,8 @@ let transfer (ctxt, sc) gas amount location parameters_ty parameters
         ~amount
         ~entrypoint
         ~parameters_ty
-        ~parameters)
+        ~parameters
+  | Event _ -> fail Event_invalid_destination)
   >>=? fun (operation, ctxt) ->
   fresh_internal_nonce ctxt >>?= fun (ctxt, nonce) ->
   let iop = {source = Contract.Originated sc.self; operation; nonce} in
diff --git a/src/proto_alpha/lib_protocol/script_interpreter_logging.ml b/src/proto_alpha/lib_protocol/script_interpreter_logging.ml
index 58a09366227ddd1a8cf39724578221569c181155..1a325f56c5d28c75196244a0b8a68f96c643b443 100644
--- a/src/proto_alpha/lib_protocol/script_interpreter_logging.ml
+++ b/src/proto_alpha/lib_protocol/script_interpreter_logging.ml
@@ -1586,6 +1586,16 @@ let kinstr_split :
              continuation = k;
              reconstruct = (fun k -> IMin_block_time (loc, k));
            }
+  | IEmit {loc; ty; addr; tag; k}, Item_t (_, s) ->
+      let s = Item_t (operation_t, s) in
+      ok
+      @@ Ex_split_kinstr
+           {
+             cont_init_stack = s;
+             continuation = k;
+             reconstruct = (fun k -> IEmit {loc; ty; addr; tag; k});
+           }
+  | IEmit _, Bot_t -> .
   | IHalt loc, _s -> ok @@ Ex_split_halt loc
   | ILog (loc, _stack_ty, event, logger, continuation), stack ->
       ok
diff --git a/src/proto_alpha/lib_protocol/script_ir_translator.ml b/src/proto_alpha/lib_protocol/script_ir_translator.ml
index 314297165775ad4f3f3ebed688f0d81477d8a724..15ff0c35128189fe791969f6e98ec0b49c4cd51f 100644
--- a/src/proto_alpha/lib_protocol/script_ir_translator.ml
+++ b/src/proto_alpha/lib_protocol/script_ir_translator.ml
@@ -593,6 +593,11 @@ let hash_comparable_data ctxt ty data =
   pack_comparable_data ctxt ty data >>=? fun (bytes, ctxt) ->
   Lwt.return @@ hash_bytes ctxt bytes
 
+let hash_event_ty ctxt unparsed =
+  pack_node unparsed ctxt >>? fun (bytes, ctxt) ->
+  Gas.consume ctxt (Michelson_v1_gas.Cost_of.Interpreter.blake2b bytes)
+  >|? fun ctxt -> (Contract_event.Hash.hash_bytes [bytes], ctxt)
+
 (* ---- Tickets ------------------------------------------------------------ *)
 
 (*
@@ -1489,6 +1494,7 @@ let parse_storage_ty :
           (Ex_ty ty, ctxt))
   | _ -> (parse_normal_storage_ty [@tailcall]) ctxt ~stack_depth ~legacy node
 
+(* check_packable: determine if a `ty` is packable into Michelson *)
 let check_packable ~legacy loc root =
   let rec check : type t tc. (t, tc) ty -> unit tzresult = function
     (* /!\ When adding new lazy storage kinds, be sure to return an error. /!\
@@ -2538,7 +2544,7 @@ let[@coq_axiom_with_reason "gadt"] rec parse_data :
         >>=? fun (({destination; entrypoint = _}, (contents, amount)), ctxt) ->
         match destination with
         | Contract ticketer -> return ({ticketer; contents; amount}, ctxt)
-        | Tx_rollup _ | Sc_rollup _ ->
+        | Tx_rollup _ | Sc_rollup _ | Event _ ->
             fail (Unexpected_ticket_owner destination)
       else traced_fail (Unexpected_forged_value (location expr))
   (* Sets *)
@@ -4639,6 +4645,14 @@ and[@coq_axiom_with_reason "gadt"] parse_instr :
       Item_t (Chest_key_t, Item_t (Chest_t, Item_t (Nat_t, rest))) ) ->
       let instr = {apply = (fun k -> IOpen_chest (loc, k))} in
       typed ctxt loc instr (Item_t (union_bytes_bool_t, rest))
+  | Prim (loc, I_EMIT, [ty_node], annot), Item_t (data, rest) ->
+      parse_packable_ty ctxt ~stack_depth:(stack_depth + 1) ~legacy ty_node
+      >>?= fun (Ex_ty ty, ctxt) ->
+      check_item_ty ctxt ty data loc I_EMIT 1 2 >>?= fun (Eq, ctxt) ->
+      parse_entrypoint_annot_strict loc annot >>?= fun tag ->
+      hash_event_ty ctxt ty_node >>?= fun (addr, ctxt) ->
+      let instr = {apply = (fun k -> IEmit {loc; tag; ty = data; addr; k})} in
+      typed ctxt loc instr (Item_t (Operation_t, rest))
   (* Primitive parsing errors *)
   | ( Prim
         ( loc,
@@ -4663,7 +4677,7 @@ and[@coq_axiom_with_reason "gadt"] parse_instr :
         ( loc,
           (( I_NONE | I_LEFT | I_RIGHT | I_NIL | I_MAP | I_ITER | I_EMPTY_SET
            | I_LOOP | I_LOOP_LEFT | I_CONTRACT | I_CAST | I_UNPACK
-           | I_CREATE_CONTRACT ) as name),
+           | I_CREATE_CONTRACT | I_EMIT ) as name),
           (([] | _ :: _ :: _) as l),
           _ ),
       _ ) ->
@@ -4993,6 +5007,7 @@ and[@coq_axiom_with_reason "complex mutually recursive definition"] parse_contra
               entrypoint_arg >|? fun (entrypoint, arg_ty) ->
               let address = {destination; entrypoint} in
               Typed_contract {arg_ty; address} ))
+  | Event _ -> return (error ctxt (fun _ -> No_such_entrypoint entrypoint))
 
 (* Same as [parse_contract], but does not fail when the contact is missing or
    if the expected type doesn't match the actual one. In that case None is
diff --git a/src/proto_alpha/lib_protocol/script_ir_translator.mli b/src/proto_alpha/lib_protocol/script_ir_translator.mli
index 8cd92a8d6a4daec238bc4f7ff2bd98c1d0766b0f..995a6aa199650148a4fe299a333dd8fd2e1fa2c2 100644
--- a/src/proto_alpha/lib_protocol/script_ir_translator.mli
+++ b/src/proto_alpha/lib_protocol/script_ir_translator.mli
@@ -191,6 +191,7 @@ val parse_comparable_data :
   Script.node ->
   ('a * context) tzresult Lwt.t
 
+(* Parsing a Micheline node data into an IR-typed data. *)
 val parse_data :
   ?type_logger:type_logger ->
   context ->
@@ -200,6 +201,7 @@ val parse_data :
   Script.node ->
   ('a * context) tzresult Lwt.t
 
+(* Unparsing an IR-typed data back into a Micheline node data *)
 val unparse_data :
   context ->
   unparsing_mode ->
@@ -425,6 +427,12 @@ val hash_data :
   'a ->
   (Script_expr_hash.t * context) tzresult Lwt.t
 
+(** [hash_event_ty ctxt ty_node] generates a contract event address
+    from the original Michelson type as specified by
+    the original node [ty_node] while accounting for the necessary gas *)
+val hash_event_ty :
+  context -> Script.node -> (Contract_event.t * context) tzresult
+
 type lazy_storage_ids
 
 val no_lazy_storage_id : lazy_storage_ids
diff --git a/src/proto_alpha/lib_protocol/script_tc_errors.ml b/src/proto_alpha/lib_protocol/script_tc_errors.ml
index 1f0c39d222b8bda47d16e6cd30e5bca766cbb951..9b2b1edbc5d571a17816254da742ebd4480c8e77 100644
--- a/src/proto_alpha/lib_protocol/script_tc_errors.ml
+++ b/src/proto_alpha/lib_protocol/script_tc_errors.ml
@@ -80,6 +80,9 @@ type error += Tx_rollup_addresses_disabled of Script.location
 
 type error += Sc_rollup_disabled of Script.location
 
+(* Event errors *)
+type error += Event_invalid_destination of Script.location
+
 (* Instruction typing errors *)
 type error += Fail_not_in_tail_position of Script.location
 
diff --git a/src/proto_alpha/lib_protocol/script_tc_errors_registration.ml b/src/proto_alpha/lib_protocol/script_tc_errors_registration.ml
index 70b586a528edb42f72d9a28b7fd7e8c357fefed5..9ed007b23a80c42efa3a1d5ebedd2770eea9d711 100644
--- a/src/proto_alpha/lib_protocol/script_tc_errors_registration.ml
+++ b/src/proto_alpha/lib_protocol/script_tc_errors_registration.ml
@@ -273,6 +273,17 @@ let () =
     (obj1 (req "location" Script.location_encoding))
     (function Sc_rollup_disabled loc -> Some loc | _ -> None)
     (fun loc -> Sc_rollup_disabled loc) ;
+  (* Event bad parameter *)
+  register_error_kind
+    `Permanent
+    ~id:"michelson_v1.event_invalid_destination"
+    ~title:"Event parameter is malformed"
+    ~description:
+      "An event address is not a valid destination to transfer any token to. \
+       Events should be sent with EMIT instructions."
+    (obj1 (req "location" Script.location_encoding))
+    (function Event_invalid_destination loc -> Some loc | _ -> None)
+    (fun loc -> Event_invalid_destination loc) ;
   (* Duplicate entrypoint *)
   register_error_kind
     `Permanent
diff --git a/src/proto_alpha/lib_protocol/script_typed_ir.ml b/src/proto_alpha/lib_protocol/script_typed_ir.ml
index ca2bac4a1ef47403669b181a912ed8c8c51cc024..cc5879aa236bfd5c8992b06f9d66e75cfd742d88 100644
--- a/src/proto_alpha/lib_protocol/script_typed_ir.ml
+++ b/src/proto_alpha/lib_protocol/script_typed_ir.ml
@@ -1083,6 +1083,14 @@ and ('before_top, 'before, 'result_top, 'result) kinstr =
            'r,
            'f )
          kinstr
+  | IEmit : {
+      loc : Script.location;
+      addr : Contract_event.t;
+      tag : Entrypoint.t;
+      ty : ('a, _) ty;
+      k : (operation, 's, 'r, 'f) kinstr;
+    }
+      -> ('a, 's, 'r, 'f) kinstr
   (*
      Internal control instructions
      -----------------------------
@@ -1357,6 +1365,12 @@ and 'kind manager_operation =
       unparsed_parameters : Script.expr;
     }
       -> Kind.transaction manager_operation
+  | Transaction_to_event : {
+      addr : Contract_event.t;
+      tag : Entrypoint.t;
+      unparsed_data : Script.expr;
+    }
+      -> Kind.transaction manager_operation
   | Origination : {
       delegate : Signature.Public_key_hash.t option;
       code : Script.expr;
@@ -1413,6 +1427,7 @@ let manager_kind : type kind. kind manager_operation -> kind Kind.manager =
   | Transaction_to_contract _ -> Kind.Transaction_manager_kind
   | Transaction_to_tx_rollup _ -> Kind.Transaction_manager_kind
   | Transaction_to_sc_rollup _ -> Kind.Transaction_manager_kind
+  | Transaction_to_event _ -> Kind.Transaction_manager_kind
   | Origination _ -> Kind.Origination_manager_kind
   | Delegation _ -> Kind.Delegation_manager_kind
 
@@ -1572,9 +1587,10 @@ let kinstr_location : type a s b f. (a, s, b, f) kinstr -> Script.location =
   | IRead_ticket (loc, _, _) -> loc
   | ISplit_ticket (loc, _) -> loc
   | IJoin_tickets (loc, _, _) -> loc
+  | IOpen_chest (loc, _) -> loc
+  | IEmit {loc; _} -> loc
   | IHalt loc -> loc
   | ILog (loc, _, _, _, _) -> loc
-  | IOpen_chest (loc, _) -> loc
 
 let meta_basic = {size = Type_size.one}
 
@@ -1973,6 +1989,7 @@ let kinstr_traverse i init f =
     | ISplit_ticket (_, k) -> (next [@ocaml.tailcall]) k
     | IJoin_tickets (_, _, k) -> (next [@ocaml.tailcall]) k
     | IOpen_chest (_, k) -> (next [@ocaml.tailcall]) k
+    | IEmit {k; _} -> (next [@ocaml.tailcall]) k
     | IHalt _ -> (return [@ocaml.tailcall]) ()
     | ILog (_, _, _, _, k) -> (next [@ocaml.tailcall]) k
   in
diff --git a/src/proto_alpha/lib_protocol/script_typed_ir.mli b/src/proto_alpha/lib_protocol/script_typed_ir.mli
index 6a87cd3433730a2383e8995e2e1634cb4ccfd9ac..35eee3e9b30a72ab6d7f8f12ec0d169155bfb143 100644
--- a/src/proto_alpha/lib_protocol/script_typed_ir.mli
+++ b/src/proto_alpha/lib_protocol/script_typed_ir.mli
@@ -1080,6 +1080,14 @@ and ('before_top, 'before, 'result_top, 'result) kinstr =
            'r,
            'f )
          kinstr
+  | IEmit : {
+      loc : Script.location;
+      addr : Contract_event.t;
+      tag : Entrypoint.t;
+      ty : ('a, _) ty;
+      k : (operation, 's, 'r, 'f) kinstr;
+    }
+      -> ('a, 's, 'r, 'f) kinstr
   (*
 
      Internal control instructions
@@ -1493,6 +1501,12 @@ and 'kind manager_operation =
       unparsed_parameters : Script.expr;
     }
       -> Kind.transaction manager_operation
+  | Transaction_to_event : {
+      addr : Contract_event.t;
+      tag : Entrypoint.t;
+      unparsed_data : Script.expr;
+    }
+      -> Kind.transaction manager_operation
   | Origination : {
       delegate : Signature.Public_key_hash.t option;
       code : Script.expr;
diff --git a/src/proto_alpha/lib_protocol/script_typed_ir_size.ml b/src/proto_alpha/lib_protocol/script_typed_ir_size.ml
index 7113b344c145066b0f162c6c0503581495f71003..661ac6846d39e325a134a1e223b54e2ba050de94 100644
--- a/src/proto_alpha/lib_protocol/script_typed_ir_size.ml
+++ b/src/proto_alpha/lib_protocol/script_typed_ir_size.ml
@@ -582,6 +582,13 @@ and kinstr_size :
     | IJoin_tickets (_, cty, _) ->
         ret_succ_adding (accu ++ ty_size cty) (base +! word_size)
     | IOpen_chest (_, _) -> ret_succ_adding accu base
+    | IEmit {loc = _; tag; ty; addr = _; k = _} ->
+        ret_succ_adding
+          (accu ++ ty_size ty)
+          (base
+          +! Entrypoint.in_memory_size tag
+          +! (word_size *? 3)
+          +! Saturation_repr.safe_int Contract_event.Hash.size)
     | IHalt _ -> ret_succ_adding accu h1w
     | ILog _ ->
         (* This instruction is ignored because it is only used for testing. *)
diff --git a/src/proto_alpha/lib_protocol/test/helpers/block.ml b/src/proto_alpha/lib_protocol/test/helpers/block.ml
index 29ea1dc32e7c775ff676366d2292973d49d4b7dd..953b74c3071ddb642f50c6f56cc7f75e817afd64 100644
--- a/src/proto_alpha/lib_protocol/test/helpers/block.ml
+++ b/src/proto_alpha/lib_protocol/test/helpers/block.ml
@@ -772,7 +772,8 @@ let bake_n_with_all_balance_updates ?(baking_mode = Application) ?policy
               | Sc_rollup_publish_result _ | Sc_rollup_refute_result _
               | Sc_rollup_timeout_result _
               | Sc_rollup_execute_outbox_message_result _
-              | Sc_rollup_recover_bond_result _ ->
+              | Sc_rollup_recover_bond_result _
+              | Transaction_result (Transaction_to_event_result _) ->
                   balance_updates_rev
               | Transaction_result
                   ( Transaction_to_contract_result {balance_updates; _}
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/contracts/emit.tz b/src/proto_alpha/lib_protocol/test/integration/michelson/contracts/emit.tz
new file mode 100644
index 0000000000000000000000000000000000000000..e57179214e091e05a204c353de1b67f73e0ed7e6
--- /dev/null
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/contracts/emit.tz
@@ -0,0 +1,16 @@
+parameter unit;
+storage unit;
+code { DROP ;
+       UNIT ;
+       PUSH string "right" ;
+       RIGHT nat ;
+       EMIT %tag1 (or (nat %int) (string %str)) ;
+       PUSH nat 2 ;
+       LEFT string ;
+       EMIT %tag2 (or (nat %int) (string %str)) ;
+       NIL operation ;
+       SWAP ;
+       CONS ;
+       SWAP ;
+       CONS ;
+       PAIR }
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/main.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/main.ml
index bee2ed0453d1662e7e95b5d28b0194add6ad2d1c..ae8d90161a219b7511644c75b0c46ca1da703f69 100644
--- a/src/proto_alpha/lib_protocol/test/integration/michelson/main.ml
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/main.ml
@@ -53,5 +53,6 @@ let () =
       ("script cache", Test_script_cache.tests);
       ("block time instructions", Test_block_time_instructions.tests);
       ("annotations", Test_annotations.tests);
+      ("event logging", Test_contract_event.tests);
     ]
   |> Lwt_main.run
diff --git a/src/proto_alpha/lib_protocol/test/integration/michelson/test_contract_event.ml b/src/proto_alpha/lib_protocol/test/integration/michelson/test_contract_event.ml
new file mode 100644
index 0000000000000000000000000000000000000000..1823b52adb918d20e64119250f9fbd1ecf57c9d0
--- /dev/null
+++ b/src/proto_alpha/lib_protocol/test/integration/michelson/test_contract_event.ml
@@ -0,0 +1,160 @@
+(*****************************************************************************)
+(*                                                                           *)
+(* Open Source License                                                       *)
+(* Copyright (c) 2022 Marigold, <contact@marigold.dev>                       *)
+(*                                                                           *)
+(* 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.                                                 *)
+(*                                                                           *)
+(*****************************************************************************)
+
+open Protocol
+open Alpha_context
+open Lwt_result_syntax
+
+(** Testing
+    -------
+    Component:  Protocol (event logging)
+    Invocation: dune exec \
+                src/proto_alpha/lib_protocol/test/integration/michelson/main.exe \
+                -- test '^event logging$'
+    Subject:  This module tests that the event logs can be written to the receipt
+              in correct order and expected format.
+*)
+
+let wrap m = m >|= Environment.wrap_tzresult
+
+(** Parse a Michelson contract from string. *)
+let originate_contract file storage src b =
+  let load_file f =
+    let ic = open_in f in
+    let res = really_input_string ic (in_channel_length ic) in
+    close_in ic ;
+    res
+  in
+  let contract_string = load_file file in
+  let code = Expr.toplevel_from_string contract_string in
+  let storage = Expr.from_string storage in
+  let script =
+    Alpha_context.Script.{code = lazy_expr code; storage = lazy_expr storage}
+  in
+  let* operation, dst =
+    Op.contract_origination (B b) src ~fee:(Test_tez.of_int 10) ~script
+  in
+  let* incr = Incremental.begin_construction b in
+  let* incr = Incremental.add_operation incr operation in
+  let+ b = Incremental.finalize_block incr in
+  (dst, b)
+
+(** Run emit.tz and assert that both the order of events and data content are correct *)
+let contract_test () =
+  let* b, src = Context.init1 ~consensus_threshold:0 () in
+  let* dst, b = originate_contract "contracts/emit.tz" "Unit" src b in
+  let fee = Test_tez.of_int 10 in
+  let parameters = Script.unit_parameter in
+  let* operation =
+    Op.transaction ~fee ~parameters (B b) src dst (Test_tez.of_int 0)
+  in
+  let* incr = Incremental.begin_construction b in
+  let* incr = Incremental.add_operation incr operation in
+  match Incremental.rev_tickets incr with
+  | [
+   Operation_metadata
+     {
+       contents =
+         Single_result
+           (Manager_operation_result
+             {
+               internal_operation_results =
+                 [
+                   Internal_manager_operation_result
+                     ( {
+                         operation =
+                           Transaction
+                             {
+                               entrypoint = tag1;
+                               parameters = data1;
+                               amount = amount1;
+                               destination = Destination.Event addr1;
+                             };
+                         _;
+                       },
+                       Applied
+                         (ITransaction_result (Transaction_to_event_result _))
+                     );
+                   Internal_manager_operation_result
+                     ( {
+                         operation =
+                           Transaction
+                             {
+                               entrypoint = tag2;
+                               parameters = data2;
+                               amount = amount2;
+                               destination = Destination.Event addr2;
+                             };
+                         _;
+                       },
+                       Applied
+                         (ITransaction_result (Transaction_to_event_result _))
+                     );
+                 ];
+               _;
+             });
+     };
+  ] ->
+      let ctxt = Gas.set_unlimited (Incremental.alpha_ctxt incr) in
+      let* data1, ctxt =
+        Lwt.return @@ Environment.wrap_tzresult
+        @@ Script.force_decode_in_context
+             ~consume_deserialization_gas:When_needed
+             ctxt
+             data1
+      in
+      let* data2, _ =
+        Lwt.return @@ Environment.wrap_tzresult
+        @@ Script.force_decode_in_context
+             ~consume_deserialization_gas:When_needed
+             ctxt
+             data2
+      in
+      let open Micheline in
+      ((match root data1 with
+       | Prim (_, D_Right, [String (_, "right")], _) -> ()
+       | _ -> assert false) ;
+
+       match root data2 with
+       | Prim (_, D_Left, [Int (_, n)], _) -> assert (Z.to_int n = 2)
+       | _ -> assert false) ;
+      let addr1 = Contract_event.to_b58check addr1 in
+      let addr2 = Contract_event.to_b58check addr2 in
+      assert (Entrypoint.to_string tag1 = "tag1") ;
+      assert (Entrypoint.to_string tag2 = "tag2") ;
+      assert (addr1 = "ev12m5E1yW14mc9rsrcdGAWVfDSdmRGuctykrVU55bHZBGv9kmdhW") ;
+      assert (addr2 = "ev12m5E1yW14mc9rsrcdGAWVfDSdmRGuctykrVU55bHZBGv9kmdhW") ;
+      assert (Tez.(amount1 = zero)) ;
+      assert (Tez.(amount2 = zero)) ;
+      return_unit
+  | _ -> assert false
+
+let tests =
+  [
+    Tztest.tztest
+      "contract emits event with correct data in proper order"
+      `Quick
+      contract_test;
+  ]
diff --git a/src/proto_alpha/lib_protocol/test/unit/test_destination_repr.ml b/src/proto_alpha/lib_protocol/test/unit/test_destination_repr.ml
index 6bb7638b99f2388a62d184df835bc627c4933ad4..51d2d1b23c746807634f01b94df671eaf5616d4d 100644
--- a/src/proto_alpha/lib_protocol/test/unit/test_destination_repr.ml
+++ b/src/proto_alpha/lib_protocol/test/unit/test_destination_repr.ml
@@ -81,6 +81,9 @@ let tx_rollup_address = "txr1YNMEtkj5Vkqsbdmt7xaxBTMRZjzS96UAi"
 *)
 let sc_rollup_address = "scr1HLXM32GacPNDrhHDLAssZG88eWqCUbyLF"
 
+(* The following address has been extracted from [../integration/michelson/test_emit.ml]. *)
+let event_address = "ev12m5E1yW14mc9rsrcdGAWVfDSdmRGuctykrVU55bHZBGv9kmdhW"
+
 let assert_compat contract destination =
   match destination with
   | Destination_repr.Contract contract'
@@ -180,11 +183,13 @@ let test_compare_destination () =
   let kt1 = !!(Destination_repr.of_b58check liquidity_baking_dex) in
   let txr1 = !!(Destination_repr.of_b58check tx_rollup_address) in
   let scr1 = !!(Destination_repr.of_b58check sc_rollup_address) in
+  let ev1 = !!(Destination_repr.of_b58check event_address) in
 
   assert (Destination_repr.(tz1 < kt1)) ;
   assert (Destination_repr.(kt1 < txr1)) ;
   assert (Destination_repr.(tz1 < txr1)) ;
   assert (Destination_repr.(txr1 < scr1)) ;
+  assert (Destination_repr.(scr1 < ev1)) ;
 
   return_unit
 
diff --git a/src/proto_alpha/lib_protocol/ticket_operations_diff.ml b/src/proto_alpha/lib_protocol/ticket_operations_diff.ml
index 26a022546c0f79eb6699f6b042eee3b565b16e7e..d965bb84155a86449fa4ce0089acbfc354428319 100644
--- a/src/proto_alpha/lib_protocol/ticket_operations_diff.ml
+++ b/src/proto_alpha/lib_protocol/ticket_operations_diff.ml
@@ -234,7 +234,7 @@ let tickets_of_operation ctxt ~allow_zero_amount_tickets
         ~preorigination
         ~storage_type
         ~storage
-  | Delegation _ -> return (None, ctxt)
+  | Delegation _ | Transaction_to_event _ -> return (None, ctxt)
 
 let add_transfer_to_token_map ctxt token_map {destination; tickets} =
   List.fold_left_es
diff --git a/tests_python/contracts_alpha/opcodes/emit.tz b/tests_python/contracts_alpha/opcodes/emit.tz
new file mode 100644
index 0000000000000000000000000000000000000000..8d758d903e7c4e251f52c80860e6d6c7435742d1
--- /dev/null
+++ b/tests_python/contracts_alpha/opcodes/emit.tz
@@ -0,0 +1,16 @@
+{ parameter unit ;
+  storage unit ;
+  code { DROP ;
+         UNIT ;
+         PUSH nat 10 ;
+         LEFT string ;
+         EMIT %event (or (nat %number) (string %words)) ;
+         PUSH string "lorem ipsum" ;
+         RIGHT nat ;
+         EMIT %event (or (nat %number) (string %words)) ;
+         NIL operation ;
+         SWAP ;
+         CONS ;
+         SWAP ;
+         CONS ;
+         PAIR } }
\ No newline at end of file
diff --git a/tests_python/tests_alpha/_regtest_outputs/test_contract.TestScriptHashRegression::test_contract_hash[client_regtest_custom_scrubber0].out b/tests_python/tests_alpha/_regtest_outputs/test_contract.TestScriptHashRegression::test_contract_hash[client_regtest_custom_scrubber0].out
index 4b6d78f0ba4e7d615123c4659fc30613334b94fd..c3202dcb353f1fef84aeb0238a90ed36dc95189a 100644
--- a/tests_python/tests_alpha/_regtest_outputs/test_contract.TestScriptHashRegression::test_contract_hash[client_regtest_custom_scrubber0].out
+++ b/tests_python/tests_alpha/_regtest_outputs/test_contract.TestScriptHashRegression::test_contract_hash[client_regtest_custom_scrubber0].out
@@ -167,6 +167,7 @@ exprujbvaRkoroj5eVgboUyeP3578oJgScTQ78eBYMgfdLVaGWPPTW	[CONTRACT_PATH]/opcodes/d
 exprur99uFkrwM63FXSTqSTypHcfEmzb5KQ9EypTRqZWDY5NP6tCHL	[CONTRACT_PATH]/opcodes/dup-n.tz
 exprtarW6tiguR7YAo6SxhCUDs1pLDhx9xJEG78h6GnXLAWpt3H1pT	[CONTRACT_PATH]/opcodes/ediv.tz
 exprvQhRaLYxiWN3QsJgT6VKf6DmGVuXR8DxeU63P9A8iNWA4TVQfs	[CONTRACT_PATH]/opcodes/ediv_mutez.tz
+exprtnW41ZGRWUYs6dHuHJm9W6Hw1CYynpQMWiEt9NxR8mysqK43XT	[CONTRACT_PATH]/opcodes/emit.tz
 exprv8Sy3DsiKMm3ZQPmi46kZGn9ctTigpLB2t6xYFdYkkeVHMXy6z	[CONTRACT_PATH]/opcodes/empty_map.tz
 exprufqf2G8PoZN768K2YGex6M7zmz7bYHE5LF5QHJBVvFtAFLi6qr	[CONTRACT_PATH]/opcodes/exec_concat.tz
 exprut53jocMPdPP8FXrKRDYSoRaxk1FXqCt7o46ak2wQaocjsSwwx	[CONTRACT_PATH]/opcodes/first.tz
diff --git a/tests_python/tests_alpha/_regtest_outputs/test_contract.TestTypecheck::test_typecheck[opcodes--emit.tz].out b/tests_python/tests_alpha/_regtest_outputs/test_contract.TestTypecheck::test_typecheck[opcodes--emit.tz].out
new file mode 100644
index 0000000000000000000000000000000000000000..06520e911c7ba97ecd1b7b8bec24cf538fedf162
--- /dev/null
+++ b/tests_python/tests_alpha/_regtest_outputs/test_contract.TestTypecheck::test_typecheck[opcodes--emit.tz].out
@@ -0,0 +1,34 @@
+tests_alpha/test_contract.py::TestTypecheck::test_typecheck[opcodes/emit.tz]
+
+Well typed
+Gas remaining: 1039987.674 units remaining
+{ parameter unit ;
+  storage unit ;
+  code { DROP
+         /* [] */ ;
+         UNIT
+         /* [ unit ] */ ;
+         PUSH nat 10
+         /* [ nat : unit ] */ ;
+         LEFT string
+         /* [ or nat string : unit ] */ ;
+         EMIT %event (or (nat %number) (string %words))
+         /* [ operation : unit ] */ ;
+         PUSH string "lorem ipsum"
+         /* [ string : operation : unit ] */ ;
+         RIGHT nat
+         /* [ or nat string : operation : unit ] */ ;
+         EMIT %event (or (nat %number) (string %words))
+         /* [ operation : operation : unit ] */ ;
+         NIL operation
+         /* [ list operation : operation : operation : unit ] */ ;
+         SWAP
+         /* [ operation : list operation : operation : unit ] */ ;
+         CONS
+         /* [ list operation : operation : unit ] */ ;
+         SWAP
+         /* [ operation : list operation : unit ] */ ;
+         CONS
+         /* [ list operation : unit ] */ ;
+         PAIR
+         /* [ pair (list operation) unit ] */ } }
diff --git a/tests_python/tests_alpha/_regtest_outputs/test_contract_opcodes.TestContractOpcodes::test_contract_input_output[emit.tz-Unit-Unit-Unit].out b/tests_python/tests_alpha/_regtest_outputs/test_contract_opcodes.TestContractOpcodes::test_contract_input_output[emit.tz-Unit-Unit-Unit].out
new file mode 100644
index 0000000000000000000000000000000000000000..3497655daa1ac26988a342bbfde2632b4db1f33c
--- /dev/null
+++ b/tests_python/tests_alpha/_regtest_outputs/test_contract_opcodes.TestContractOpcodes::test_contract_input_output[emit.tz-Unit-Unit-Unit].out
@@ -0,0 +1,74 @@
+tests_alpha/test_contract_opcodes.py::TestContractOpcodes::test_contract_input_output[emit.tz-Unit-Unit-Unit]
+
+storage
+  Unit
+emitted operations
+  Internal Transaction:
+    Amount: ꜩ0
+    From: KT1BEqzn5Wx8uJrZNvuS9DVHmLvG9td3fDLi
+    To: ev13o2yWTf9YocjZXWyyHhuTDzoeDuKKe2RmKp9sBnPFeywtpdFsp
+    Entrypoint: event
+    Parameter: (Left 10)
+  Internal Transaction:
+    Amount: ꜩ0
+    From: KT1BEqzn5Wx8uJrZNvuS9DVHmLvG9td3fDLi
+    To: ev13o2yWTf9YocjZXWyyHhuTDzoeDuKKe2RmKp9sBnPFeywtpdFsp
+    Entrypoint: event
+    Parameter: (Right "lorem ipsum")
+big_map diff
+  
+trace
+  - location: 7 (remaining gas: 1039983.624 units remaining)
+    [ (Pair Unit Unit) ]
+  - location: 7 (remaining gas: 1039983.614 units remaining)
+    [  ]
+  - location: 8 (remaining gas: 1039983.604 units remaining)
+    [ Unit ]
+  - location: 9 (remaining gas: 1039983.594 units remaining)
+    [ 10
+      Unit ]
+  - location: 12 (remaining gas: 1039983.584 units remaining)
+    [ (Left 10)
+      Unit ]
+  - location: 14 (remaining gas: 1039983.362 units remaining)
+    [ 0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a
+      Unit ]
+  - location: 18 (remaining gas: 1039983.352 units remaining)
+    [ "lorem ipsum"
+      0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a
+      Unit ]
+  - location: 21 (remaining gas: 1039983.342 units remaining)
+    [ (Right "lorem ipsum")
+      0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a
+      Unit ]
+  - location: 23 (remaining gas: 1039983.120 units remaining)
+    [ 0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000001010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000120508010000000b6c6f72656d20697073756d
+      0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a
+      Unit ]
+  - location: 27 (remaining gas: 1039983.110 units remaining)
+    [ {}
+      0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000001010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000120508010000000b6c6f72656d20697073756d
+      0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a
+      Unit ]
+  - location: 29 (remaining gas: 1039983.100 units remaining)
+    [ 0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000001010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000120508010000000b6c6f72656d20697073756d
+      {}
+      0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a
+      Unit ]
+  - location: 30 (remaining gas: 1039983.090 units remaining)
+    [ { 0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000001010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000120508010000000b6c6f72656d20697073756d }
+      0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a
+      Unit ]
+  - location: 31 (remaining gas: 1039983.080 units remaining)
+    [ 0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a
+      { 0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000001010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000120508010000000b6c6f72656d20697073756d }
+      Unit ]
+  - location: 32 (remaining gas: 1039983.070 units remaining)
+    [ { 0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a ;
+        0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000001010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000120508010000000b6c6f72656d20697073756d }
+      Unit ]
+  - location: 33 (remaining gas: 1039983.060 units remaining)
+    [ (Pair { 0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000000010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000040505000a ;
+              0x011d23c1d3d2f8a4ea5e8784b8f7ecf2ad304c0fe6000001010004ac785bfba0f68d61a64f5baa2d45550f6494440a2831f1387df36f41dd770fdd00ffff056576656e74000000120508010000000b6c6f72656d20697073756d }
+            Unit) ]
+
diff --git a/tests_python/tests_alpha/test_contract_opcodes.py b/tests_python/tests_alpha/test_contract_opcodes.py
index 11dfb9167d3f216785e7785c0a2a5126ef95a663..fb1254e60712319648c936778eba64103879c42b 100644
--- a/tests_python/tests_alpha/test_contract_opcodes.py
+++ b/tests_python/tests_alpha/test_contract_opcodes.py
@@ -46,6 +46,7 @@ class TestContractOpcodes:
                 '{ 1 ; 2 ; 3 ; 0 }',
                 '{ 1 ; 3 ; 5 ; 3 }',
             ),
+            ('emit.tz', 'Unit', 'Unit', 'Unit'),
             # Reverse a list
             ('reverse.tz', '{""}', '{}', '{}'),
             (
diff --git a/tezt/lib_tezos/RPC_legacy.ml b/tezt/lib_tezos/RPC_legacy.ml
index 50b40eb92ee360b35539000e2505d8d4df1bf539..6a3671465c3039ab9c41a73475161a410100271e 100644
--- a/tezt/lib_tezos/RPC_legacy.ml
+++ b/tezt/lib_tezos/RPC_legacy.ml
@@ -217,6 +217,13 @@ let post_simulate_operation ?endpoint ?hooks ?(chain = "main") ?(block = "head")
   in
   Client.rpc ?endpoint ?hooks ~data POST path client
 
+let post_compute_event_address ?endpoint ?hooks ?(chain = "main")
+    ?(block = "head") ~data client =
+  let path =
+    ["chains"; chain; "blocks"; block; "helpers"; "scripts"; "event_address"]
+  in
+  Client.rpc ?endpoint ?hooks ~data POST path client
+
 module Big_maps = struct
   let get ?endpoint ?hooks ?(chain = "main") ?(block = "head") ~id ~key_hash
       client =
diff --git a/tezt/lib_tezos/RPC_legacy.mli b/tezt/lib_tezos/RPC_legacy.mli
index 3da2ecb5b11a7cebd5fe1b23255861347f663665..be1c439cb359f44715942dbb9cd21b9fb98e77ae 100644
--- a/tezt/lib_tezos/RPC_legacy.mli
+++ b/tezt/lib_tezos/RPC_legacy.mli
@@ -195,6 +195,16 @@ val post_simulate_operation :
   Client.t ->
   JSON.t Lwt.t
 
+(** Call RPC /chain/[chain]/blocks/[block]/helpers/scripts/event_address *)
+val post_compute_event_address :
+  ?endpoint:Client.endpoint ->
+  ?hooks:Process.hooks ->
+  ?chain:string ->
+  ?block:string ->
+  data:JSON.u ->
+  Client.t ->
+  JSON.t Lwt.t
+
 (** {2 Protocol RPCs} *)
 
 type ctxt_type = Bytes | Json
diff --git a/tezt/lib_tezos/client.ml b/tezt/lib_tezos/client.ml
index 921987916535afbba65241304591697f4fd88e8b..fae0916e808396414db54048fdf48b5fa57136dc 100644
--- a/tezt/lib_tezos/client.ml
+++ b/tezt/lib_tezos/client.ml
@@ -1890,6 +1890,13 @@ let contract_storage ?unparsing_mode address client =
     @ optional_arg "unparsing-mode" normalize_mode_to_string unparsing_mode)
   |> Process.check_and_read_stdout
 
+let contract_code ?unparsing_mode address client =
+  spawn_command
+    client
+    (["get"; "contract"; "code"; "for"; address]
+    @ optional_arg "unparsing-mode" normalize_mode_to_string unparsing_mode)
+  |> Process.check_and_read_stdout
+
 let sign_bytes ~signer ~data client =
   let* output =
     spawn_command client ["sign"; "bytes"; data; "for"; signer]
diff --git a/tezt/lib_tezos/client.mli b/tezt/lib_tezos/client.mli
index 62f4bd513e4b4a38c66fe418ba3045950f671c03..feb253e9d7680e385de4efb56a53a06550b4c39f 100644
--- a/tezt/lib_tezos/client.mli
+++ b/tezt/lib_tezos/client.mli
@@ -1409,6 +1409,11 @@ val register_key : string -> t -> unit Lwt.t
 val contract_storage :
   ?unparsing_mode:normalize_mode -> string -> t -> string Lwt.t
 
+(** Get contract code for a contract. Returns a Micheline expression
+    representing the code as a string. *)
+val contract_code :
+  ?unparsing_mode:normalize_mode -> string -> t -> string Lwt.t
+
 (** Sign a string of bytes with secret key of the given account. *)
 val sign_bytes : signer:string -> data:string -> t -> string Lwt.t
 
diff --git a/tezt/tests/contracts/proto_alpha/emit_events.tz b/tezt/tests/contracts/proto_alpha/emit_events.tz
new file mode 100644
index 0000000000000000000000000000000000000000..3a14c0dc185495e372e1385830f6a6cc29157dc9
--- /dev/null
+++ b/tezt/tests/contracts/proto_alpha/emit_events.tz
@@ -0,0 +1,16 @@
+parameter unit;
+storage unit;
+code { DROP;
+       UNIT;
+       PUSH string "right";
+       RIGHT nat;
+       EMIT %tag1 (or (nat %int) (string %str)) ;
+       PUSH nat 2;
+       LEFT string;
+       EMIT %tag2 (or (nat %int) (string %str)) ;
+       NIL operation ;
+       SWAP ;
+       CONS ;
+       SWAP ;
+       CONS ;
+       PAIR }
\ No newline at end of file
diff --git a/tezt/tests/events.ml b/tezt/tests/events.ml
new file mode 100644
index 0000000000000000000000000000000000000000..aad40dc8c9a7b13c1417d3b4c54dc1cb48eb11ec
--- /dev/null
+++ b/tezt/tests/events.ml
@@ -0,0 +1,101 @@
+(*****************************************************************************)
+(*                                                                           *)
+(* Open Source License                                                       *)
+(* Copyright (c) 2022 Marigold <contact@marigold.dev>                        *)
+(*                                                                           *)
+(* 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.                                                 *)
+(*                                                                           *)
+(*****************************************************************************)
+
+(* Testing
+   -------
+   Components: Client
+   Invocation: dune exec tezt/tests/main.exe -- check_client_events
+   Subject: Test that the client shows the contract events in correct order
+*)
+
+let test_emit_event protocol =
+  let* node = Node.init [Synchronisation_threshold 0; Connections 0] in
+  let* client = Client.init ~endpoint:(Node node) () in
+  let* () = Client.activate_protocol ~protocol client in
+  let* _ = Node.wait_for_level node 1 in
+  let* contract_id =
+    Client.originate_contract
+      ~alias:"emit_events.tz"
+      ~amount:Tez.zero
+      ~src:"bootstrap1"
+      ~prg:"file:./tezt/tests/contracts/proto_alpha/emit_events.tz"
+      ~init:"Unit"
+      ~burn_cap:Tez.one
+      client
+  in
+  let* () = Client.bake_for client in
+  let* () =
+    Client.transfer
+      ~gas_limit:100_000
+      ~fee:Tez.one
+      ~amount:Tez.zero
+      ~burn_cap:Tez.one
+      ~storage_limit:10000
+      ~giver:"bootstrap1"
+      ~receiver:contract_id
+      ~arg:"Unit"
+      ~force:true
+      client
+  in
+  let* () = Client.bake_for client in
+  let* first_manager_operation =
+    Client.rpc
+      Client.GET
+      ["chains"; "main"; "blocks"; "head"; "operations"; "3"; "0"]
+      client
+  in
+  let open JSON in
+  let events =
+    first_manager_operation |-> "contents" |=> 0 |-> "metadata"
+    |-> "internal_operation_results"
+  in
+  let event = events |=> 0 in
+  assert (
+    event |-> "destination" |> as_string
+    = "ev12m5E1yW14mc9rsrcdGAWVfDSdmRGuctykrVU55bHZBGv9kmdhW") ;
+  let data = event |-> "parameters" |-> "value" in
+  assert (data |-> "prim" |> as_string = "Right") ;
+  assert (data |-> "args" |=> 0 |-> "string" |> as_string = "right") ;
+  let tag = event |-> "parameters" |-> "entrypoint" |> as_string in
+  assert (tag = "tag1") ;
+  let event = events |=> 1 in
+  assert (
+    event |-> "destination" |> as_string
+    = "ev12m5E1yW14mc9rsrcdGAWVfDSdmRGuctykrVU55bHZBGv9kmdhW") ;
+  let data = event |-> "parameters" |-> "value" in
+  assert (data |-> "prim" |> as_string = "Left") ;
+  assert (data |-> "args" |=> 0 |-> "int" |> as_string = "2") ;
+  let tag = event |-> "parameters" |-> "entrypoint" |> as_string in
+  assert (tag = "tag2") ;
+  return ()
+
+let check_client_events =
+  Protocol.register_test
+    ~__FILE__
+    ~title:"Events: events from client"
+    ~tags:["check_client_events"]
+    test_emit_event
+
+let register ~protocols = check_client_events protocols
diff --git a/tezt/tests/main.ml b/tezt/tests/main.ml
index d1dde59d9a8678e5043c78e01bb8603a9a5af7c3..6cfcbcdeb07ad78f820fb8285a46f40a26490c19 100644
--- a/tezt/tests/main.ml
+++ b/tezt/tests/main.ml
@@ -128,6 +128,7 @@ let () =
   Client_run_view.register ~protocols:[Alpha; Jakarta] ;
   Multinode_snapshot.register ~protocols:[Alpha] ;
   Config.register () ;
+  Events.register ~protocols:[Alpha] ;
   (* Relies on a feature only available since K. *)
   Op_validation.register ~protocols ;
   (* Test.run () should be the last statement, don't register afterwards! *)