Merge pull request #12958 from ydb-platform/merge-libs-241224-2313

43 files changed, 226 insertions, 189 deletions

diff --git a/yt/cpp/mapreduce/client/batch_request_impl.cpp b/yt/cpp/mapreduce/client/batch_request_impl.cpp
index 08ffec2bfc..d8084e9c45 100644
--- a/yt/cpp/mapreduce/client/batch_request_impl.cpp
+++ b/yt/cpp/mapreduce/client/batch_request_impl.cpp
@@ -50,7 +50,7 @@ TBatchRequest::~TBatchRequest() = default;
 IBatchRequestBase& TBatchRequest::WithTransaction(const TTransactionId& transactionId)
 {
     if (!TmpWithTransaction_) {
-        TmpWithTransaction_.Reset(new TBatchRequest(Impl_.Get(), Client_));
+        TmpWithTransaction_.reset(new TBatchRequest(Impl_.Get(), Client_));
     }
     TmpWithTransaction_->DefaultTransaction_ = transactionId;
     return *TmpWithTransaction_;
diff --git a/yt/cpp/mapreduce/client/batch_request_impl.h b/yt/cpp/mapreduce/client/batch_request_impl.h
index 0a176417b3..a4d776668f 100644
--- a/yt/cpp/mapreduce/client/batch_request_impl.h
+++ b/yt/cpp/mapreduce/client/batch_request_impl.h
@@ -124,7 +124,7 @@ private:
 private:
     TTransactionId DefaultTransaction_;
     ::TIntrusivePtr<NDetail::NRawClient::TRawBatchRequest> Impl_;
-    THolder<TBatchRequest> TmpWithTransaction_;
+    std::unique_ptr<TBatchRequest> TmpWithTransaction_;
     ::TIntrusivePtr<TClient> Client_;
 
 private:
diff --git a/yt/cpp/mapreduce/client/client.cpp b/yt/cpp/mapreduce/client/client.cpp
index 9fcb82f5b7..7d73756759 100644
--- a/yt/cpp/mapreduce/client/client.cpp
+++ b/yt/cpp/mapreduce/client/client.cpp
@@ -940,7 +940,7 @@ TTransaction::TTransaction(
     : TClientBase(rawClient, context, parentTransactionId, parentClient->GetRetryPolicy())
     , TransactionPinger_(parentClient->GetTransactionPinger())
     , PingableTx_(
-        MakeHolder<TPingableTransaction>(
+        std::make_unique<TPingableTransaction>(
             rawClient,
             parentClient->GetRetryPolicy(),
             context,
@@ -1434,7 +1434,7 @@ TYtPoller& TClient::GetYtPoller()
         // We don't use current client and create new client because YtPoller_ might use
         // this client during current client shutdown.
         // That might lead to incrementing of current client refcount and double delete of current client object.
-        YtPoller_ = MakeHolder<TYtPoller>(Context_, ClientRetryPolicy_);
+        YtPoller_ = std::make_unique<TYtPoller>(Context_, ClientRetryPolicy_);
     }
     return *YtPoller_;
 }
diff --git a/yt/cpp/mapreduce/client/client.h b/yt/cpp/mapreduce/client/client.h
index 32a0f9a97e..4ceb7f69b3 100644
--- a/yt/cpp/mapreduce/client/client.h
+++ b/yt/cpp/mapreduce/client/client.h
@@ -333,7 +333,7 @@ protected:
 
 private:
     ITransactionPingerPtr TransactionPinger_;
-    THolder<TPingableTransaction> PingableTx_;
+    std::unique_ptr<TPingableTransaction> PingableTx_;
     TClientPtr ParentClient_;
 };
 
@@ -502,7 +502,7 @@ private:
 
     std::atomic<bool> Shutdown_ = false;
     TMutex Lock_;
-    THolder<TYtPoller> YtPoller_;
+    std::unique_ptr<TYtPoller> YtPoller_;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/yt/cpp/mapreduce/client/client_reader.cpp b/yt/cpp/mapreduce/client/client_reader.cpp
index e7538a22da..b144b70c02 100644
--- a/yt/cpp/mapreduce/client/client_reader.cpp
+++ b/yt/cpp/mapreduce/client/client_reader.cpp
@@ -58,7 +58,7 @@ TClientReader::TClientReader(
 {
     if (options.CreateTransaction_) {
         Y_ABORT_UNLESS(transactionPinger, "Internal error: transactionPinger is null");
-        ReadTransaction_ = MakeHolder<TPingableTransaction>(
+        ReadTransaction_ = std::make_unique<TPingableTransaction>(
             RawClient_,
             ClientRetryPolicy_,
             Context_,
diff --git a/yt/cpp/mapreduce/client/client_reader.h b/yt/cpp/mapreduce/client/client_reader.h
index 3f73080046..cc78d2f3d3 100644
--- a/yt/cpp/mapreduce/client/client_reader.h
+++ b/yt/cpp/mapreduce/client/client_reader.h
@@ -51,7 +51,7 @@ private:
     TMaybe<TFormat> Format_;
     TTableReaderOptions Options_;
 
-    THolder<TPingableTransaction> ReadTransaction_;
+    std::unique_ptr<TPingableTransaction> ReadTransaction_;
 
     std::unique_ptr<IInputStream> Input_;
 
diff --git a/yt/cpp/mapreduce/client/file_reader.cpp b/yt/cpp/mapreduce/client/file_reader.cpp
index f88b40e38b..1682212f1d 100644
--- a/yt/cpp/mapreduce/client/file_reader.cpp
+++ b/yt/cpp/mapreduce/client/file_reader.cpp
@@ -47,7 +47,7 @@ TStreamReaderBase::TStreamReaderBase(
     const TTransactionId& transactionId)
     : RawClient_(rawClient)
     , ClientRetryPolicy_(std::move(clientRetryPolicy))
-    , ReadTransaction_(MakeHolder<TPingableTransaction>(
+    , ReadTransaction_(std::make_unique<TPingableTransaction>(
         RawClient_,
         ClientRetryPolicy_,
         context,
diff --git a/yt/cpp/mapreduce/client/file_reader.h b/yt/cpp/mapreduce/client/file_reader.h
index 8aafdc860d..d3efe90f26 100644
--- a/yt/cpp/mapreduce/client/file_reader.h
+++ b/yt/cpp/mapreduce/client/file_reader.h
@@ -45,7 +45,7 @@ private:
 
     std::unique_ptr<IInputStream> Input_;
 
-    THolder<TPingableTransaction> ReadTransaction_;
+    std::unique_ptr<TPingableTransaction> ReadTransaction_;
 
     ui64 CurrentOffset_ = 0;
 };
diff --git a/yt/cpp/mapreduce/client/init.cpp b/yt/cpp/mapreduce/client/init.cpp
index 6121952f86..78c92ee883 100644
--- a/yt/cpp/mapreduce/client/init.cpp
+++ b/yt/cpp/mapreduce/client/init.cpp
@@ -219,11 +219,11 @@ void ExecJob(int argc, const char** argv, const TInitializeOptions& options)
 
         NDetail::OutputTableCount = static_cast<i64>(outputTableCount);
 
-        THolder<IInputStream> jobStateStream;
+        std::unique_ptr<IInputStream> jobStateStream;
         if (hasState) {
-            jobStateStream = MakeHolder<TIFStream>("jobstate");
+            jobStateStream = std::make_unique<TIFStream>("jobstate");
         } else {
-            jobStateStream = MakeHolder<TBufferStream>(0);
+            jobStateStream = std::make_unique<TBufferStream>(0);
         }
 
         int ret = 1;
diff --git a/yt/cpp/mapreduce/client/operation.cpp b/yt/cpp/mapreduce/client/operation.cpp
index 98ed246e0e..9441c7efe2 100644
--- a/yt/cpp/mapreduce/client/operation.cpp
+++ b/yt/cpp/mapreduce/client/operation.cpp
@@ -969,9 +969,9 @@ void BuildIntermediateDataPart(const TSpec& spec, TNode* nodeSpec)
 
 TNode MergeSpec(TNode dst, TNode spec, const TOperationOptions& options)
 {
-    MergeNodes(dst["spec"], spec);
+    MergeNodes(dst, spec);
     if (options.Spec_) {
-        MergeNodes(dst["spec"], *options.Spec_);
+        MergeNodes(dst, *options.Spec_);
     }
     return dst;
 }
@@ -1129,7 +1129,7 @@ void DoExecuteMap(
     spec.Title_ = spec.Title_.GetOrElse(AddModeToTitleIfDebug(map.GetClassName()));
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .Item("mapper").DoMap([&] (TFluentMap fluent) {
             BuildUserJobFluently(
                 map,
@@ -1148,18 +1148,18 @@ void DoExecuteMap(
         .DoIf(spec.Ordered_.Defined(), [&] (TFluentMap fluent) {
             fluent.Item("ordered").Value(spec.Ordered_.GetRef());
         })
-    .EndMap().EndMap();
+    .EndMap();
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
 
-    specNode["spec"]["job_io"]["control_attributes"]["enable_row_index"] = TNode(true);
-    specNode["spec"]["job_io"]["control_attributes"]["enable_range_index"] = TNode(true);
+    specNode["job_io"]["control_attributes"]["enable_row_index"] = TNode(true);
+    specNode["job_io"]["control_attributes"]["enable_range_index"] = TNode(true);
     if (!preparer->GetContext().Config->TableWriter.Empty()) {
-        specNode["spec"]["job_io"]["table_writer"] = preparer->GetContext().Config->TableWriter;
+        specNode["job_io"]["table_writer"] = preparer->GetContext().Config->TableWriter;
     }
 
-    BuildCommonUserOperationPart(spec, &specNode["spec"]);
-    BuildJobCountOperationPart(spec, &specNode["spec"]);
+    BuildCommonUserOperationPart(spec, &specNode);
+    BuildJobCountOperationPart(spec, &specNode);
 
     auto startOperation = [
         operation=operation.Get(),
@@ -1168,7 +1168,7 @@ void DoExecuteMap(
         operationIo,
         mapper
     ] () {
-        auto operationId = preparer->StartOperation(operation, "map", spec);
+        auto operationId = preparer->StartOperation(operation, EOperationType::Map, spec);
 
         LogJob(operationId, mapper.Get(), "mapper");
         LogYPaths(operationId, operationIo.Inputs, "input");
@@ -1247,7 +1247,7 @@ void DoExecuteReduce(
     spec.Title_ = spec.Title_.GetOrElse(AddModeToTitleIfDebug(reduce.GetClassName()));
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .Item("reducer").DoMap([&] (TFluentMap fluent) {
             BuildUserJobFluently(
                 reduce,
@@ -1280,11 +1280,11 @@ void DoExecuteReduce(
         .DoIf(spec.AutoMerge_.Defined(), [&] (TFluentMap fluent) {
             fluent.Item("auto_merge").Value(BuildAutoMergeSpec(*spec.AutoMerge_));
         })
-    .EndMap().EndMap();
+    .EndMap();
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
-    BuildCommonUserOperationPart(spec, &specNode["spec"]);
-    BuildJobCountOperationPart(spec, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
+    BuildCommonUserOperationPart(spec, &specNode);
+    BuildJobCountOperationPart(spec, &specNode);
 
     auto startOperation = [
         operation=operation.Get(),
@@ -1293,7 +1293,7 @@ void DoExecuteReduce(
         operationIo,
         reducer
     ] () {
-        auto operationId = preparer->StartOperation(operation, "reduce", spec);
+        auto operationId = preparer->StartOperation(operation, EOperationType::Reduce, spec);
 
         LogJob(operationId, reducer.Get(), "reducer");
         LogYPaths(operationId, operationIo.Inputs, "input");
@@ -1373,7 +1373,7 @@ void DoExecuteJoinReduce(
     spec.Title_ = spec.Title_.GetOrElse(AddModeToTitleIfDebug(reduce.GetClassName()));
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .Item("reducer").DoMap([&] (TFluentMap fluent) {
             BuildUserJobFluently(
                 reduce,
@@ -1394,11 +1394,11 @@ void DoExecuteJoinReduce(
                 fluent.Item("table_writer").Value(preparer->GetContext().Config->TableWriter);
             })
         .EndMap()
-    .EndMap().EndMap();
+    .EndMap();
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
-    BuildCommonUserOperationPart(spec, &specNode["spec"]);
-    BuildJobCountOperationPart(spec, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
+    BuildCommonUserOperationPart(spec, &specNode);
+    BuildJobCountOperationPart(spec, &specNode);
 
     auto startOperation = [
         operation=operation.Get(),
@@ -1407,7 +1407,7 @@ void DoExecuteJoinReduce(
         reducer,
         operationIo
     ] () {
-        auto operationId = preparer->StartOperation(operation, "join_reduce", spec);
+        auto operationId = preparer->StartOperation(operation, EOperationType::JoinReduce, spec);
 
         LogJob(operationId, reducer.Get(), "reducer");
         LogYPaths(operationId, operationIo.Inputs, "input");
@@ -1505,7 +1505,7 @@ void DoExecuteMapReduce(
     TString title;
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .DoIf(hasMapper, [&] (TFluentMap fluent) {
             TJobPreparer map(
                 *preparer,
@@ -1584,18 +1584,18 @@ void DoExecuteMapReduce(
         .Do([&] (TFluentMap) {
             spec.Title_ = spec.Title_.GetOrElse(AddModeToTitleIfDebug(title + "reducer:" + reduce.GetClassName()));
         })
-    .EndMap().EndMap();
+    .EndMap();
 
     if (spec.Ordered_) {
-        specNode["spec"]["ordered"] = *spec.Ordered_;
+        specNode["ordered"] = *spec.Ordered_;
     }
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
-    BuildCommonUserOperationPart(spec, &specNode["spec"]);
-    BuildMapJobCountOperationPart(spec, &specNode["spec"]);
-    BuildPartitionCountOperationPart(spec, &specNode["spec"]);
-    BuildIntermediateDataPart(spec, &specNode["spec"]);
-    BuildDataSizePerSortJobPart(spec, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
+    BuildCommonUserOperationPart(spec, &specNode);
+    BuildMapJobCountOperationPart(spec, &specNode);
+    BuildPartitionCountOperationPart(spec, &specNode);
+    BuildIntermediateDataPart(spec, &specNode);
+    BuildDataSizePerSortJobPart(spec, &specNode);
 
     auto startOperation = [
         operation=operation.Get(),
@@ -1607,7 +1607,7 @@ void DoExecuteMapReduce(
         inputs=operationIo.Inputs,
         allOutputs
     ] () {
-        auto operationId = preparer->StartOperation(operation, "map_reduce", spec);
+        auto operationId = preparer->StartOperation(operation, EOperationType::MapReduce, spec);
 
         LogJob(operationId, mapper.Get(), "mapper");
         LogJob(operationId, reduceCombiner.Get(), "reduce_combiner");
@@ -1962,19 +1962,19 @@ void ExecuteSort(
     }
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .Item("input_table_paths").List(inputs)
         .Item("output_table_path").Value(output)
         .Item("sort_by").Value(spec.SortBy_)
         .DoIf(spec.SchemaInferenceMode_.Defined(), [&] (TFluentMap fluent) {
             fluent.Item("schema_inference_mode").Value(ToString(*spec.SchemaInferenceMode_));
         })
-    .EndMap().EndMap();
+    .EndMap();
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
-    BuildPartitionCountOperationPart(spec, &specNode["spec"]);
-    BuildPartitionJobCountOperationPart(spec, &specNode["spec"]);
-    BuildIntermediateDataPart(spec, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
+    BuildPartitionCountOperationPart(spec, &specNode);
+    BuildPartitionJobCountOperationPart(spec, &specNode);
+    BuildIntermediateDataPart(spec, &specNode);
 
     auto startOperation = [
         operation=operation.Get(),
@@ -1983,7 +1983,7 @@ void ExecuteSort(
         inputs,
         output
     ] () {
-        auto operationId = preparer->StartOperation(operation, "sort", spec);
+        auto operationId = preparer->StartOperation(operation, EOperationType::Sort, spec);
 
         LogYPaths(operationId, inputs, "input");
         LogYPath(operationId, output, "output");
@@ -2011,7 +2011,7 @@ void ExecuteMerge(
     }
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .Item("input_table_paths").List(inputs)
         .Item("output_table_path").Value(output)
         .Item("mode").Value(ToString(spec.Mode_))
@@ -2021,10 +2021,10 @@ void ExecuteMerge(
         .DoIf(spec.SchemaInferenceMode_.Defined(), [&] (TFluentMap fluent) {
             fluent.Item("schema_inference_mode").Value(ToString(*spec.SchemaInferenceMode_));
         })
-    .EndMap().EndMap();
+    .EndMap();
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
-    BuildJobCountOperationPart(spec, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
+    BuildJobCountOperationPart(spec, &specNode);
 
     auto startOperation = [
         operation=operation.Get(),
@@ -2033,7 +2033,7 @@ void ExecuteMerge(
         inputs,
         output
     ] () {
-        auto operationId = preparer->StartOperation(operation, "merge", spec);
+        auto operationId = preparer->StartOperation(operation, EOperationType::Merge, spec);
 
         LogYPaths(operationId, inputs, "input");
         LogYPath(operationId, output, "output");
@@ -2055,22 +2055,22 @@ void ExecuteErase(
     auto tablePath = NRawClient::CanonizeYPath(nullptr, preparer->GetContext(), spec.TablePath_);
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .Item("table_path").Value(tablePath)
         .Item("combine_chunks").Value(spec.CombineChunks_)
         .DoIf(spec.SchemaInferenceMode_.Defined(), [&] (TFluentMap fluent) {
             fluent.Item("schema_inference_mode").Value(ToString(*spec.SchemaInferenceMode_));
         })
-    .EndMap().EndMap();
+    .EndMap();
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
     auto startOperation = [
         operation=operation.Get(),
         spec=MergeSpec(std::move(specNode), preparer->GetContext().Config->Spec, options),
         preparer,
         tablePath
     ] () {
-        auto operationId = preparer->StartOperation(operation, "erase", spec);
+        auto operationId = preparer->StartOperation(operation, EOperationType::Erase, spec);
 
         LogYPath(operationId, tablePath, "table_path");
 
@@ -2098,7 +2098,7 @@ void ExecuteRemoteCopy(
     Y_ENSURE_EX(!spec.ClusterName_.empty(), TApiUsageError() << "ClusterName parameter is required");
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .Item("cluster_name").Value(spec.ClusterName_)
         .Item("input_table_paths").List(inputs)
         .Item("output_table_path").Value(output)
@@ -2115,9 +2115,9 @@ void ExecuteRemoteCopy(
                 "doesn't make sense without CopyAttributes == true");
             fluent.Item("attribute_keys").List(spec.AttributeKeys_);
         })
-    .EndMap().EndMap();
+    .EndMap();
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
     auto startOperation = [
         operation=operation.Get(),
         spec=MergeSpec(specNode, preparer->GetContext().Config->Spec, options),
@@ -2125,7 +2125,7 @@ void ExecuteRemoteCopy(
         inputs,
         output
     ] () {
-        auto operationId = preparer->StartOperation(operation, "remote_copy", spec);
+        auto operationId = preparer->StartOperation(operation, EOperationType::RemoteCopy, spec);
 
         LogYPaths(operationId, inputs, "input");
         LogYPath(operationId, output, "output");
@@ -2222,15 +2222,15 @@ void ExecuteVanilla(
     }
 
     TNode specNode = BuildYsonNodeFluently()
-    .BeginMap().Item("spec").BeginMap()
+    .BeginMap()
         .Item("tasks").DoMapFor(spec.Tasks_, addTask)
-    .EndMap().EndMap();
+    .EndMap();
 
-    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode["spec"]);
-    BuildCommonUserOperationPart(spec, &specNode["spec"]);
+    BuildCommonOperationPart(preparer->GetContext().Config, spec, options, &specNode);
+    BuildCommonUserOperationPart(spec, &specNode);
 
     auto startOperation = [operation=operation.Get(), spec=MergeSpec(std::move(specNode), preparer->GetContext().Config->Spec, options), preparer] () {
-        auto operationId = preparer->StartOperation(operation, "vanilla", spec, /* useStartOperationRequest */ true);
+        auto operationId = preparer->StartOperation(operation, EOperationType::Vanilla, spec);
         return operationId;
     };
 
@@ -2784,7 +2784,7 @@ void TOperation::TOperationImpl::AsyncFinishOperation(TOperationAttributes opera
 
 void* TOperation::TOperationImpl::SyncFinishOperationProc(void* pArgs)
 {
-    THolder<TAsyncFinishOperationsArgs> args(static_cast<TAsyncFinishOperationsArgs*>(pArgs));
+    std::unique_ptr<TAsyncFinishOperationsArgs> args(static_cast<TAsyncFinishOperationsArgs*>(pArgs));
     args->OperationImpl->SyncFinishOperationImpl(args->OperationAttributes);
     return nullptr;
 }
@@ -3013,7 +3013,7 @@ struct TAsyncPrepareAndStartOperationArgs
 
 void* SyncPrepareAndStartOperation(void* pArgs)
 {
-    THolder<TAsyncPrepareAndStartOperationArgs> args(static_cast<TAsyncPrepareAndStartOperationArgs*>(pArgs));
+    std::unique_ptr<TAsyncPrepareAndStartOperationArgs> args(static_cast<TAsyncPrepareAndStartOperationArgs*>(pArgs));
     args->PrepareAndStart();
     return nullptr;
 }
diff --git a/yt/cpp/mapreduce/client/operation_preparer.cpp b/yt/cpp/mapreduce/client/operation_preparer.cpp
index e8e4ee26d2..70bd5f8b65 100644
--- a/yt/cpp/mapreduce/client/operation_preparer.cpp
+++ b/yt/cpp/mapreduce/client/operation_preparer.cpp
@@ -37,7 +37,7 @@ class TWaitOperationStartPollerItem
     : public IYtPollerItem
 {
 public:
-    TWaitOperationStartPollerItem(TOperationId operationId, THolder<TPingableTransaction> transaction)
+    TWaitOperationStartPollerItem(TOperationId operationId, std::unique_ptr<TPingableTransaction> transaction)
         : OperationId_(operationId)
         , Transaction_(std::move(transaction))
     { }
@@ -78,7 +78,7 @@ public:
 
 private:
     TOperationId OperationId_;
-    THolder<TPingableTransaction> Transaction_;
+    std::unique_ptr<TPingableTransaction> Transaction_;
     ::NThreading::TFuture<TOperationAttributes> Future_;
 };
 
@@ -139,7 +139,7 @@ private:
 TOperationPreparer::TOperationPreparer(TClientPtr client, TTransactionId transactionId)
     : Client_(std::move(client))
     , TransactionId_(transactionId)
-    , FileTransaction_(MakeHolder<TPingableTransaction>(
+    , FileTransaction_(std::make_unique<TPingableTransaction>(
         Client_->GetRawClient(),
         Client_->GetRetryPolicy(),
         Client_->GetContext(),
@@ -177,35 +177,26 @@ const IClientRetryPolicyPtr& TOperationPreparer::GetClientRetryPolicy() const
 
 TOperationId TOperationPreparer::StartOperation(
     TOperation* operation,
-    const TString& operationType,
-    const TNode& spec,
-    bool useStartOperationRequest)
+    EOperationType type,
+    const TNode& spec)
 {
     CheckValidity();
 
-    THttpHeader header("POST", (useStartOperationRequest ? "start_op" : operationType));
-    if (useStartOperationRequest) {
-        header.AddParameter("operation_type", operationType);
-    }
-    header.AddTransactionId(TransactionId_);
-    header.AddMutationId();
-
-    auto ysonSpec = NodeToYsonString(spec);
-    auto responseInfo = RetryRequestWithPolicy(
+    auto operationId = RequestWithRetry<TOperationId>(
         ::MakeIntrusive<TOperationForwardingRequestRetryPolicy>(
             ClientRetryPolicy_->CreatePolicyForStartOperationRequest(),
             TOperationPtr(operation)),
-        GetContext(),
-        header,
-        ysonSpec);
-    TOperationId operationId = ParseGuidFromResponse(responseInfo.Response);
+        [this, &type, &spec] (TMutationId& mutationId) {
+            return Client_->GetRawClient()->StartOperation(mutationId, TransactionId_, type, spec);
+        });
+
     YT_LOG_DEBUG("Operation started (OperationId: %v; PreparationId: %v)",
         operationId,
         GetPreparationId());
 
     YT_LOG_INFO("Operation %v started (%v): %v",
         operationId,
-        operationType,
+        type,
         GetOperationWebInterfaceUrl(GetContext().ServerName, operationId));
 
     TOperationExecutionTimeTracker::Get()->Start(operationId);
@@ -305,9 +296,9 @@ public:
         return result;
     }
 
-    THolder<IInputStream> CreateInputStream() const override
+    std::unique_ptr<IInputStream> CreateInputStream() const override
     {
-        return MakeHolder<TFileInput>(FileName_);
+        return std::make_unique<TFileInput>(FileName_);
     }
 
     TString GetDescription() const override
@@ -343,9 +334,9 @@ public:
         return result;
     }
 
-    THolder<IInputStream> CreateInputStream() const override
+    std::unique_ptr<IInputStream> CreateInputStream() const override
     {
-        return MakeHolder<TMemoryInput>(Data_.data(), Data_.size());
+        return std::make_unique<TMemoryInput>(Data_.data(), Data_.size());
     }
 
     TString GetDescription() const override
diff --git a/yt/cpp/mapreduce/client/operation_preparer.h b/yt/cpp/mapreduce/client/operation_preparer.h
index 90fd91378c..ef3a790c91 100644
--- a/yt/cpp/mapreduce/client/operation_preparer.h
+++ b/yt/cpp/mapreduce/client/operation_preparer.h
@@ -28,16 +28,15 @@ public:
 
     TOperationId StartOperation(
         TOperation* operation,
-        const TString& operationType,
-        const TNode& spec,
-        bool useStartOperationRequest = false);
+        EOperationType type,
+        const TNode& spec);
 
     const IClientRetryPolicyPtr& GetClientRetryPolicy() const;
 
 private:
     TClientPtr Client_;
     TTransactionId TransactionId_;
-    THolder<TPingableTransaction> FileTransaction_;
+    std::unique_ptr<TPingableTransaction> FileTransaction_;
     IClientRetryPolicyPtr ClientRetryPolicy_;
     const TString PreparationId_;
 
@@ -54,7 +53,7 @@ struct IItemToUpload
     virtual ~IItemToUpload() = default;
 
     virtual TString CalculateMD5() const = 0;
-    virtual THolder<IInputStream> CreateInputStream() const = 0;
+    virtual std::unique_ptr<IInputStream> CreateInputStream() const = 0;
     virtual TString GetDescription() const = 0;
     virtual i64 GetDataSize() const = 0;
 };
diff --git a/yt/cpp/mapreduce/client/retry_heavy_write_request.cpp b/yt/cpp/mapreduce/client/retry_heavy_write_request.cpp
index 44c7db3a97..80f54d2340 100644
--- a/yt/cpp/mapreduce/client/retry_heavy_write_request.cpp
+++ b/yt/cpp/mapreduce/client/retry_heavy_write_request.cpp
@@ -31,7 +31,7 @@ void RetryHeavyWriteRequest(
     const TClientContext& context,
     const TTransactionId& parentId,
     THttpHeader& header,
-    std::function<THolder<IInputStream>()> streamMaker)
+    std::function<std::unique_ptr<IInputStream>()> streamMaker)
 {
     int retryCount = context.Config->RetryCount;
     if (context.ServiceTicketAuth) {
@@ -63,7 +63,7 @@ void RetryHeavyWriteRequest(
                 GetFullUrlForProxy(hostName, context, header),
                 requestId,
                 header);
-            TransferData(input.Get(), request->GetStream());
+            TransferData(input.get(), request->GetStream());
             request->Finish()->GetResponse();
         } catch (TErrorResponse& e) {
             YT_LOG_ERROR("RSP %v - attempt %v failed",
@@ -100,7 +100,7 @@ THeavyRequestRetrier::THeavyRequestRetrier(TParameters parameters)
     : Parameters_(std::move(parameters))
     , RequestRetryPolicy_(Parameters_.ClientRetryPolicy->CreatePolicyForGenericRequest())
     , StreamFactory_([] {
-        return MakeHolder<TNullInput>();
+        return std::make_unique<TNullInput>();
     })
 {
     Retry([] { });
diff --git a/yt/cpp/mapreduce/client/retry_heavy_write_request.h b/yt/cpp/mapreduce/client/retry_heavy_write_request.h
index 6933170e96..b65f457239 100644
--- a/yt/cpp/mapreduce/client/retry_heavy_write_request.h
+++ b/yt/cpp/mapreduce/client/retry_heavy_write_request.h
@@ -26,7 +26,7 @@ public:
         THttpHeader Header;
     };
 
-    using TStreamFactory = std::function<THolder<IInputStream>()>;
+    using TStreamFactory = std::function<std::unique_ptr<IInputStream>()>;
 
 public:
     explicit THeavyRequestRetrier(TParameters parameters);
@@ -65,7 +65,7 @@ void RetryHeavyWriteRequest(
     const TClientContext& context,
     const TTransactionId& parentId,
     THttpHeader& header,
-    std::function<THolder<IInputStream>()> streamMaker);
+    std::function<std::unique_ptr<IInputStream>()> streamMaker);
 
 ////////////////////////////////////////////////////////////////////////////////
 
diff --git a/yt/cpp/mapreduce/client/retryful_writer.cpp b/yt/cpp/mapreduce/client/retryful_writer.cpp
index 41ad1298cd..666229d7a6 100644
--- a/yt/cpp/mapreduce/client/retryful_writer.cpp
+++ b/yt/cpp/mapreduce/client/retryful_writer.cpp
@@ -104,7 +104,7 @@ void TRetryfulWriter::Send(const TBuffer& buffer)
     header.MergeParameters(Parameters_);
 
     auto streamMaker = [&buffer] () {
-        return MakeHolder<TBufferInput>(buffer);
+        return std::make_unique<TBufferInput>(buffer);
     };
 
     auto transactionId = (WriteTransaction_ ? WriteTransaction_->GetId() : ParentTransactionId_);
diff --git a/yt/cpp/mapreduce/client/retryful_writer_v2.cpp b/yt/cpp/mapreduce/client/retryful_writer_v2.cpp
index 40198baaef..c11f20ce3f 100644
--- a/yt/cpp/mapreduce/client/retryful_writer_v2.cpp
+++ b/yt/cpp/mapreduce/client/retryful_writer_v2.cpp
@@ -176,7 +176,7 @@ private:
 
     void ThreadMain(TRichYPath path, const THeavyRequestRetrier::TParameters& parameters)
     {
-        THolder<THeavyRequestRetrier> retrier;
+        std::unique_ptr<THeavyRequestRetrier> retrier;
 
         auto firstRequestParameters = parameters;
         auto restRequestParameters = parameters;
@@ -218,14 +218,14 @@ private:
 
             try {
                 if (!retrier) {
-                    retrier = MakeHolder<THeavyRequestRetrier>(*currentParameters);
+                    retrier = std::make_unique<THeavyRequestRetrier>(*currentParameters);
                 }
                 retrier->Update([task=task] {
-                    return MakeHolder<TMemoryInput>(task.Data->data(), task.Size);
+                    return std::make_unique<TMemoryInput>(task.Data->data(), task.Size);
                 });
                 if (task.BufferComplete) {
                     retrier->Finish();
-                    retrier.Reset();
+                    retrier.reset();
                 }
             } catch (const std::exception& ex) {
                 task.SendingComplete.SetException(std::current_exception());
@@ -235,7 +235,7 @@ private:
             }
 
             if (task.BufferComplete) {
-                retrier.Reset();
+                retrier.reset();
                 task.SendingComplete.SetValue();
                 currentParameters = &restRequestParameters;
 
@@ -303,15 +303,15 @@ TRetryfulWriterV2::TRetryfulWriterV2(
     ssize_t bufferSize,
     bool createTransaction)
     : BufferSize_(bufferSize)
-    , Current_(MakeHolder<TSendTask>())
-    , Previous_(MakeHolder<TSendTask>())
+    , Current_(std::make_unique<TSendTask>())
+    , Previous_(std::make_unique<TSendTask>())
 {
     THttpHeader httpHeader("PUT", command);
     httpHeader.SetInputFormat(format);
     httpHeader.MergeParameters(serializedWriterOptions);
 
     if (createTransaction) {
-        WriteTransaction_ = MakeHolder<TPingableTransaction>(
+        WriteTransaction_ = std::make_unique<TPingableTransaction>(
             rawClient,
             clientRetryPolicy,
             context,
@@ -337,7 +337,7 @@ TRetryfulWriterV2::TRetryfulWriterV2(
         .Header = std::move(httpHeader),
     };
 
-    Sender_ = MakeHolder<TSender>(path, parameters);
+    Sender_ = std::make_unique<TSender>(path, parameters);
 
     DoStartBatch();
 }
diff --git a/yt/cpp/mapreduce/client/retryful_writer_v2.h b/yt/cpp/mapreduce/client/retryful_writer_v2.h
index 661ef5d0b5..6d314307ec 100644
--- a/yt/cpp/mapreduce/client/retryful_writer_v2.h
+++ b/yt/cpp/mapreduce/client/retryful_writer_v2.h
@@ -49,11 +49,11 @@ private:
     const ssize_t BufferSize_;
     const ssize_t SendStep_ = 64_KB;
     ssize_t NextSizeToSend_;
-    THolder<TSender> Sender_;
-    THolder<TPingableTransaction> WriteTransaction_;
+    std::unique_ptr<TSender> Sender_;
+    std::unique_ptr<TPingableTransaction> WriteTransaction_;
 
-    THolder<TSendTask> Current_;
-    THolder<TSendTask> Previous_;
+    std::unique_ptr<TSendTask> Current_;
+    std::unique_ptr<TSendTask> Previous_;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/yt/cpp/mapreduce/client/retryless_writer.h b/yt/cpp/mapreduce/client/retryless_writer.h
index 6916cddbf6..689c1c5f2f 100644
--- a/yt/cpp/mapreduce/client/retryless_writer.h
+++ b/yt/cpp/mapreduce/client/retryless_writer.h
@@ -56,7 +56,7 @@ public:
         auto hostName = GetProxyForHeavyRequest(context);
         UpdateHeaderForProxyIfNeed(hostName, context, header);
         Request_ = context.HttpClient->StartRequest(GetFullUrl(hostName, context, header), requestId, header);
-        BufferedOutput_.Reset(new TBufferedOutput(Request_->GetStream(), BufferSize_));
+        BufferedOutput_ = std::make_unique<TBufferedOutput>(Request_->GetStream(), BufferSize_);
     }
 
     ~TRetrylessWriter() override;
@@ -75,7 +75,7 @@ private:
 
     bool Running_ = true;
     NHttpClient::IHttpRequestPtr Request_;
-    THolder<TBufferedOutput> BufferedOutput_;
+    std::unique_ptr<TBufferedOutput> BufferedOutput_;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/yt/cpp/mapreduce/client/transaction_pinger.cpp b/yt/cpp/mapreduce/client/transaction_pinger.cpp
index ea42867715..074249efce 100644
--- a/yt/cpp/mapreduce/client/transaction_pinger.cpp
+++ b/yt/cpp/mapreduce/client/transaction_pinger.cpp
@@ -228,7 +228,7 @@ public:
         PingableTx_ = &pingableTx;
         Running_ = true;
 
-        PingerThread_ = MakeHolder<TThread>(
+        PingerThread_ = std::make_unique<TThread>(
             TThread::TParams{Pinger, this}.SetName("pingable_tx"));
         PingerThread_->Start();
     }
@@ -284,7 +284,7 @@ private:
     const TPingableTransaction* PingableTx_ = nullptr;
 
     std::atomic<bool> Running_ = false;
-    THolder<TThread> PingerThread_;
+    std::unique_ptr<TThread> PingerThread_;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/yt/cpp/mapreduce/http/http.cpp b/yt/cpp/mapreduce/http/http.cpp
index 51253feec2..765a96f042 100644
--- a/yt/cpp/mapreduce/http/http.cpp
+++ b/yt/cpp/mapreduce/http/http.cpp
@@ -545,7 +545,7 @@ TConnectionPtr TConnectionPool::Connect(
     TSocketHolder socket(DoConnect(networkAddress));
     SetNonBlock(socket, false);
 
-    connection->Socket.Reset(new TSocket(socket.Release()));
+    connection->Socket = std::make_unique<TSocket>(socket.Release());
 
     connection->DeadLine = TInstant::Now() + socketTimeout;
     connection->Socket->SetSocketTimeout(socketTimeout.Seconds());
@@ -754,7 +754,7 @@ private:
 THttpResponse::THttpResponse(
     TRequestContext context,
     IInputStream* socketStream)
-    : HttpInput_(MakeHolder<THttpInputWrapped>(context, socketStream))
+    : HttpInput_(std::make_unique<THttpInputWrapped>(context, socketStream))
     , Unframe_(HttpInput_->Headers().HasHeader("X-YT-Framing"))
     , Context_(std::move(context))
 {
@@ -935,7 +935,7 @@ bool THttpResponse::RefreshFrameIfNecessary()
             case EFrameType::KeepAlive:
                 break;
             case EFrameType::Data:
-                RemainingFrameSize_ = ReadDataFrameSize(HttpInput_.Get());
+                RemainingFrameSize_ = ReadDataFrameSize(HttpInput_.get());
                 break;
             default:
                 ythrow yexception() << "Bad frame type " << static_cast<int>(frameTypeByte);
@@ -1027,10 +1027,10 @@ IOutputStream* THttpRequest::StartRequestImpl(bool includeParameters)
         LogResponse_ = true;
     }
 
-    RequestStream_ = MakeHolder<TRequestStream>(this, *Connection_->Socket.Get());
+    RequestStream_ = std::make_unique<TRequestStream>(this, *Connection_->Socket.get());
 
     RequestStream_->Write(strHeader.data(), strHeader.size());
-    return RequestStream_.Get();
+    return RequestStream_.get();
 }
 
 IOutputStream* THttpRequest::StartRequest()
@@ -1064,16 +1064,16 @@ void THttpRequest::SmallRequest(TMaybe<TStringBuf> body)
 THttpResponse* THttpRequest::GetResponseStream()
 {
     if (!Input_) {
-        SocketInput_.Reset(new TSocketInput(*Connection_->Socket.Get()));
+        SocketInput_ = std::make_unique<TSocketInput>(*Connection_->Socket.get());
         if (TConfig::Get()->UseAbortableResponse) {
             Y_ABORT_UNLESS(!Url_.empty());
-            Input_.Reset(new TAbortableHttpResponse(Context_, SocketInput_.Get(), Url_));
+            Input_ = std::make_unique<TAbortableHttpResponse>(Context_, SocketInput_.get(), Url_);
         } else {
-            Input_.Reset(new THttpResponse(Context_, SocketInput_.Get()));
+            Input_ = std::make_unique<THttpResponse>(Context_, SocketInput_.get());
         }
         Input_->CheckErrorResponse();
     }
-    return Input_.Get();
+    return Input_.get();
 }
 
 TString THttpRequest::GetResponse()
diff --git a/yt/cpp/mapreduce/http/http.h b/yt/cpp/mapreduce/http/http.h
index 0f5e9034ee..45cba99861 100644
--- a/yt/cpp/mapreduce/http/http.h
+++ b/yt/cpp/mapreduce/http/http.h
@@ -138,7 +138,7 @@ private:
 
 struct TConnection
 {
-    THolder<TSocket> Socket;
+    std::unique_ptr<TSocket> Socket;
     TAtomic Busy = 1;
     TInstant DeadLine;
     ui32 Id;
@@ -206,7 +206,7 @@ private:
     class THttpInputWrapped;
 
 private:
-    THolder<THttpInputWrapped> HttpInput_;
+    std::unique_ptr<THttpInputWrapped> HttpInput_;
 
     const bool Unframe_;
 
@@ -257,10 +257,10 @@ private:
 
     TConnectionPtr Connection_;
 
-    THolder<TRequestStream> RequestStream_;
+    std::unique_ptr<TRequestStream> RequestStream_;
 
-    THolder<TSocketInput> SocketInput_;
-    THolder<THttpResponse> Input_;
+    std::unique_ptr<TSocketInput> SocketInput_;
+    std::unique_ptr<THttpResponse> Input_;
 
     bool LogResponse_ = false;
 };
diff --git a/yt/cpp/mapreduce/http/ut/connection_pool_ut.cpp b/yt/cpp/mapreduce/http/ut/connection_pool_ut.cpp
index fa072675fb..a8f6856aee 100644
--- a/yt/cpp/mapreduce/http/ut/connection_pool_ut.cpp
+++ b/yt/cpp/mapreduce/http/ut/connection_pool_ut.cpp
@@ -32,10 +32,10 @@ namespace {
     }
 } // namespace
 
-THolder<TSimpleServer> CreateSimpleHttpServer()
+std::unique_ptr<TSimpleServer> CreateSimpleHttpServer()
 {
     auto port = NTesting::GetFreePort();
-    return MakeHolder<TSimpleServer>(
+    return std::make_unique<TSimpleServer>(
         port,
         [] (IInputStream* input, IOutputStream* output) {
             try {
@@ -57,10 +57,10 @@ THolder<TSimpleServer> CreateSimpleHttpServer()
         });
 }
 
-THolder<TSimpleServer> CreateProxyHttpServer()
+std::unique_ptr<TSimpleServer> CreateProxyHttpServer()
 {
     auto port = NTesting::GetFreePort();
-    return MakeHolder<TSimpleServer>(
+    return std::make_unique<TSimpleServer>(
         port,
         [] (IInputStream* input, IOutputStream* output) {
             try {
@@ -182,9 +182,9 @@ TEST(TConnectionPool, TestConcurrency)
         }
     };
 
-    TVector<THolder<TFuncThread>> threads;
+    TVector<std::unique_ptr<TFuncThread>> threads;
     for (int i = 0; i != 10; ++i) {
-        threads.push_back(MakeHolder<TFuncThread>(func));
+        threads.push_back(std::make_unique<TFuncThread>(func));
     };
 
     for (auto& t : threads) {
diff --git a/yt/cpp/mapreduce/http/ut/http_ut.cpp b/yt/cpp/mapreduce/http/ut/http_ut.cpp
index e41e83c5a0..2d382f6aa0 100644
--- a/yt/cpp/mapreduce/http/ut/http_ut.cpp
+++ b/yt/cpp/mapreduce/http/ut/http_ut.cpp
@@ -21,10 +21,10 @@ void WriteDataFrame(TStringBuf string, IOutputStream* stream)
     stream->Write(string);
 }
 
-THolder<TSimpleServer> CreateFramingEchoServer()
+std::unique_ptr<TSimpleServer> CreateFramingEchoServer()
 {
     auto port = NTesting::GetFreePort();
-    return MakeHolder<TSimpleServer>(
+    return std::make_unique<TSimpleServer>(
         port,
         [] (IInputStream* input, IOutputStream* output) {
             try {
diff --git a/yt/cpp/mapreduce/http/ut/simple_server.cpp b/yt/cpp/mapreduce/http/ut/simple_server.cpp
index fbc369ec20..111010a83d 100644
--- a/yt/cpp/mapreduce/http/ut/simple_server.cpp
+++ b/yt/cpp/mapreduce/http/ut/simple_server.cpp
@@ -23,9 +23,9 @@ TSimpleServer::TSimpleServer(int port, TRequestHandler requestHandler)
     ret = listenSocket->Listen(10);
     Y_ENSURE_EX(ret == 0, TSystemError() << "Can not listen socket");
 
-    SendFinishSocket_ = MakeHolder<TInetStreamSocket>(socketPair[1]);
+    SendFinishSocket_ = std::make_unique<TInetStreamSocket>(socketPair[1]);
 
-    ThreadPool_ = MakeHolder<TAdaptiveThreadPool>();
+    ThreadPool_ = std::make_unique<TAdaptiveThreadPool>();
     ThreadPool_->Start(1);
 
     auto receiveFinish = MakeAtomicShared<TInetStreamSocket>(socketPair[0]);
@@ -76,7 +76,7 @@ void TSimpleServer::Stop()
     SendFinishSocket_->Send("X", 1);
     ListenerThread_->Join();
     ThreadPool_->Stop();
-    ThreadPool_.Destroy();
+    ThreadPool_.reset();
 }
 
 int TSimpleServer::GetPort() const
diff --git a/yt/cpp/mapreduce/http/ut/simple_server.h b/yt/cpp/mapreduce/http/ut/simple_server.h
index f468ca55a6..f9f7287126 100644
--- a/yt/cpp/mapreduce/http/ut/simple_server.h
+++ b/yt/cpp/mapreduce/http/ut/simple_server.h
@@ -29,7 +29,7 @@ public:
 
 private:
     const int Port_;
-    THolder<IThreadPool> ThreadPool_;
+    std::unique_ptr<IThreadPool> ThreadPool_;
     THolder<IThreadFactory::IThread> ListenerThread_;
-    THolder<TInetStreamSocket> SendFinishSocket_;
+    std::unique_ptr<TInetStreamSocket> SendFinishSocket_;
 };
diff --git a/yt/cpp/mapreduce/interface/io-inl.h b/yt/cpp/mapreduce/interface/io-inl.h
index ffaf71f0a2..056910f785 100644
--- a/yt/cpp/mapreduce/interface/io-inl.h
+++ b/yt/cpp/mapreduce/interface/io-inl.h
@@ -350,11 +350,11 @@ public:
 
         return TBase::DoGetRowCached(
             /* cacher */ [&] {
-                CachedRow_.Reset(new U);
-                Reader_->ReadRow(CachedRow_.Get());
+                CachedRow_.reset(new U);
+                Reader_->ReadRow(CachedRow_.get());
             },
             /* cacheGetter */ [&] {
-                auto result = dynamic_cast<const U*>(CachedRow_.Get());
+                auto result = dynamic_cast<const U*>(CachedRow_.get());
                 Y_ABORT_UNLESS(result);
                 return result;
             });
@@ -371,7 +371,7 @@ public:
                 Reader_->ReadRow(result);
             },
             /* cacheMover */ [&] (U* result) {
-                auto cast = dynamic_cast<U*>(CachedRow_.Get());
+                auto cast = dynamic_cast<U*>(CachedRow_.get());
                 Y_ABORT_UNLESS(cast);
                 result->Swap(cast);
             });
@@ -394,7 +394,7 @@ public:
 
 private:
     using TBase::Reader_;
-    mutable THolder<Message> CachedRow_;
+    mutable std::unique_ptr<Message> CachedRow_;
 };
 
 template<class... TProtoRowTypes>
diff --git a/yt/cpp/mapreduce/interface/raw_client.h b/yt/cpp/mapreduce/interface/raw_client.h
index 4994826863..ff2dafeb6d 100644
--- a/yt/cpp/mapreduce/interface/raw_client.h
+++ b/yt/cpp/mapreduce/interface/raw_client.h
@@ -139,6 +139,12 @@ public:
 
     // Operations
 
+    virtual TOperationId StartOperation(
+        TMutationId& mutationId,
+        const TTransactionId& transactionId,
+        EOperationType type,
+        const TNode& spec) = 0;
+
     virtual TOperationAttributes GetOperation(
         const TOperationId& operationId,
         const TGetOperationOptions& options = {}) = 0;
diff --git a/yt/cpp/mapreduce/io/node_table_reader.cpp b/yt/cpp/mapreduce/io/node_table_reader.cpp
index bc3da75ee6..558c42b30e 100644
--- a/yt/cpp/mapreduce/io/node_table_reader.cpp
+++ b/yt/cpp/mapreduce/io/node_table_reader.cpp
@@ -35,7 +35,7 @@ public:
     void Finalize();
 
 private:
-    THolder<TNodeBuilder> Builder_;
+    std::unique_ptr<TNodeBuilder> Builder_;
     TRowElement Row_;
     int Depth_ = 0;
     bool Started_ = false;
@@ -143,7 +143,7 @@ void TRowBuilder::SaveResultRow()
         *ResultRow_ = std::move(Row_);
     }
     Row_.Reset();
-    Builder_.Reset(new TNodeBuilder(&Row_.Node));
+    Builder_ = std::make_unique<TNodeBuilder>(&Row_.Node);
 }
 
 void TRowBuilder::Finalize()
@@ -346,8 +346,8 @@ bool TNodeTableReader::IsRawReaderExhausted() const
 void TNodeTableReader::PrepareParsing()
 {
     NextRow_.Clear();
-    Builder_.Reset(new TRowBuilder(&NextRow_));
-    Parser_.Reset(new ::NYson::TYsonListParser(Builder_.Get(), &Input_));
+    Builder_ = std::make_unique<TRowBuilder>(&NextRow_);
+    Parser_ = std::make_unique<::NYson::TYsonListParser>(Builder_.get(), &Input_);
 }
 
 void TNodeTableReader::OnStreamError(std::exception_ptr exception, TString error)
diff --git a/yt/cpp/mapreduce/io/node_table_reader.h b/yt/cpp/mapreduce/io/node_table_reader.h
index 38cb440632..c8e319ce4f 100644
--- a/yt/cpp/mapreduce/io/node_table_reader.h
+++ b/yt/cpp/mapreduce/io/node_table_reader.h
@@ -79,8 +79,8 @@ private:
     TMaybe<TRowElement> Row_;
     TMaybe<TRowElement> NextRow_;
 
-    THolder<TRowBuilder> Builder_;
-    THolder<::NYson::TYsonListParser> Parser_;
+    std::unique_ptr<TRowBuilder> Builder_;
+    std::unique_ptr<::NYson::TYsonListParser> Parser_;
 
     std::exception_ptr Exception_;
     bool NeedParseFirst_ = true;
diff --git a/yt/cpp/mapreduce/io/node_table_writer.cpp b/yt/cpp/mapreduce/io/node_table_writer.cpp
index 916dec7ae4..c516c7b4ee 100644
--- a/yt/cpp/mapreduce/io/node_table_writer.cpp
+++ b/yt/cpp/mapreduce/io/node_table_writer.cpp
@@ -13,11 +13,11 @@ namespace NYT {
 ////////////////////////////////////////////////////////////////////////////////
 
 TNodeTableWriter::TNodeTableWriter(THolder<IProxyOutput> output, NYson::EYsonFormat format)
-    : Output_(std::move(output))
+    : Output_(output.Release())
 {
     for (size_t i = 0; i < Output_->GetStreamCount(); ++i) {
         Writers_.push_back(
-            MakeHolder<::NYson::TYsonWriter>(Output_->GetStream(i), format, NYT::NYson::EYsonType::ListFragment));
+            std::make_unique<::NYson::TYsonWriter>(Output_->GetStream(i), format, NYT::NYson::EYsonType::ListFragment));
     }
 }
 
@@ -54,7 +54,7 @@ void TNodeTableWriter::AddRow(const TNode& row, size_t tableIndex)
         }
     }
 
-    auto* writer = Writers_[tableIndex].Get();
+    auto* writer = Writers_[tableIndex].get();
     writer->OnListItem();
 
     TNodeVisitor visitor(writer);
diff --git a/yt/cpp/mapreduce/io/node_table_writer.h b/yt/cpp/mapreduce/io/node_table_writer.h
index 155bec076d..0bc7a58557 100644
--- a/yt/cpp/mapreduce/io/node_table_writer.h
+++ b/yt/cpp/mapreduce/io/node_table_writer.h
@@ -25,8 +25,8 @@ public:
     void Abort() override;
 
 private:
-    THolder<IProxyOutput> Output_;
-    TVector<THolder<::NYson::TYsonWriter>> Writers_;
+    std::unique_ptr<IProxyOutput> Output_;
+    TVector<std::unique_ptr<::NYson::TYsonWriter>> Writers_;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/yt/cpp/mapreduce/io/proto_table_reader.h b/yt/cpp/mapreduce/io/proto_table_reader.h
index 8452545005..bfe4ac5647 100644
--- a/yt/cpp/mapreduce/io/proto_table_reader.h
+++ b/yt/cpp/mapreduce/io/proto_table_reader.h
@@ -33,7 +33,7 @@ public:
     bool IsRawReaderExhausted() const override;
 
 private:
-    THolder<TNodeTableReader> NodeReader_;
+    std::unique_ptr<TNodeTableReader> NodeReader_;
     TVector<const ::google::protobuf::Descriptor*> Descriptors_;
 };
 
diff --git a/yt/cpp/mapreduce/io/proto_table_writer.cpp b/yt/cpp/mapreduce/io/proto_table_writer.cpp
index f56784eb60..ff0dbddc71 100644
--- a/yt/cpp/mapreduce/io/proto_table_writer.cpp
+++ b/yt/cpp/mapreduce/io/proto_table_writer.cpp
@@ -102,7 +102,7 @@ TNode MakeNodeFromMessage(const Message& row)
 TProtoTableWriter::TProtoTableWriter(
     THolder<IProxyOutput> output,
     TVector<const Descriptor*>&& descriptors)
-    : NodeWriter_(new TNodeTableWriter(std::move(output)))
+    : NodeWriter_(std::make_unique<TNodeTableWriter>(std::move(output)))
     , Descriptors_(std::move(descriptors))
 { }
 
@@ -145,7 +145,7 @@ void TProtoTableWriter::Abort()
 TLenvalProtoTableWriter::TLenvalProtoTableWriter(
     THolder<IProxyOutput> output,
     TVector<const Descriptor*>&& descriptors)
-    : Output_(std::move(output))
+    : Output_(output.Release())
     , Descriptors_(std::move(descriptors))
 { }
 
diff --git a/yt/cpp/mapreduce/io/proto_table_writer.h b/yt/cpp/mapreduce/io/proto_table_writer.h
index 336230f55f..8dae9aaf79 100644
--- a/yt/cpp/mapreduce/io/proto_table_writer.h
+++ b/yt/cpp/mapreduce/io/proto_table_writer.h
@@ -27,7 +27,7 @@ public:
     void Abort() override;
 
 private:
-    THolder<TNodeTableWriter> NodeWriter_;
+    std::unique_ptr<TNodeTableWriter> NodeWriter_;
     TVector<const ::google::protobuf::Descriptor*> Descriptors_;
 };
 
@@ -51,7 +51,7 @@ public:
     void Abort() override;
 
 protected:
-    THolder<IProxyOutput> Output_;
+    std::unique_ptr<IProxyOutput> Output_;
     TVector<const ::google::protobuf::Descriptor*> Descriptors_;
 };
 
diff --git a/yt/cpp/mapreduce/io/ut/yamr_table_reader_ut.cpp b/yt/cpp/mapreduce/io/ut/yamr_table_reader_ut.cpp
index fc20be017f..b45f47c64c 100644
--- a/yt/cpp/mapreduce/io/ut/yamr_table_reader_ut.cpp
+++ b/yt/cpp/mapreduce/io/ut/yamr_table_reader_ut.cpp
@@ -56,13 +56,13 @@ public:
     TTestRawTableReader(const TRowCollection& rowCollection)
         : RowCollection_(rowCollection)
         , DataToRead_(RowCollection_.GetStreamDataStartFromRow(0))
-        , Input_(MakeHolder<TStringStream>(DataToRead_))
+        , Input_(std::make_unique<TStringStream>(DataToRead_))
     { }
 
     TTestRawTableReader(const TRowCollection& rowCollection, size_t breakPoint)
         : RowCollection_(rowCollection)
         , DataToRead_(RowCollection_.GetStreamDataStartFromRow(0).substr(0, breakPoint))
-        , Input_(MakeHolder<TStringStream>(DataToRead_))
+        , Input_(std::make_unique<TStringStream>(DataToRead_))
         , Broken_(true)
     { }
 
@@ -86,7 +86,7 @@ public:
         }
         ui64 actualRowIndex = rowIndex ? *rowIndex : 0;
         DataToRead_ = RowCollection_.GetStreamDataStartFromRow(actualRowIndex);
-        Input_ = MakeHolder<TStringInput>(DataToRead_);
+        Input_ = std::make_unique<TStringInput>(DataToRead_);
         Broken_ = false;
         return true;
     }
@@ -102,7 +102,7 @@ public:
 private:
     TRowCollection RowCollection_;
     TString DataToRead_;
-    THolder<IInputStream> Input_;
+    std::unique_ptr<IInputStream> Input_;
     bool Broken_ = false;
     i32 Retries = 1;
 };
diff --git a/yt/cpp/mapreduce/io/yamr_table_writer.cpp b/yt/cpp/mapreduce/io/yamr_table_writer.cpp
index fe31eb5543..dcfacb7541 100644
--- a/yt/cpp/mapreduce/io/yamr_table_writer.cpp
+++ b/yt/cpp/mapreduce/io/yamr_table_writer.cpp
@@ -7,7 +7,7 @@ namespace NYT {
 ////////////////////////////////////////////////////////////////////////////////
 
 TYaMRTableWriter::TYaMRTableWriter(THolder<IProxyOutput> output)
-    : Output_(std::move(output))
+    : Output_(output.Release())
 { }
 
 TYaMRTableWriter::~TYaMRTableWriter()
diff --git a/yt/cpp/mapreduce/io/yamr_table_writer.h b/yt/cpp/mapreduce/io/yamr_table_writer.h
index 7f72c8005a..f976a35832 100644
--- a/yt/cpp/mapreduce/io/yamr_table_writer.h
+++ b/yt/cpp/mapreduce/io/yamr_table_writer.h
@@ -24,7 +24,7 @@ public:
     void Abort() override;
 
 private:
-    THolder<IProxyOutput> Output_;
+    std::unique_ptr<IProxyOutput> Output_;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/yt/cpp/mapreduce/library/user_job_statistics/user_job_statistics.cpp b/yt/cpp/mapreduce/library/user_job_statistics/user_job_statistics.cpp
index 56ab88ee9d..7cc5a84e6a 100644
--- a/yt/cpp/mapreduce/library/user_job_statistics/user_job_statistics.cpp
+++ b/yt/cpp/mapreduce/library/user_job_statistics/user_job_statistics.cpp
@@ -42,8 +42,8 @@ void TUserJobStatsProxy::Init(IOutputStream * usingStream) {
 
     if (usingStream == nullptr) {
         TFileHandle fixedDesrc(JobStatisticsHandle);
-        FetchedOut = MakeHolder<TFixedBufferFileOutput>(TFile(fixedDesrc.Duplicate()));
-        UsingStream = FetchedOut.Get();
+        FetchedOut = std::make_unique<TFixedBufferFileOutput>(TFile(fixedDesrc.Duplicate()));
+        UsingStream = FetchedOut.get();
         fixedDesrc.Release();
     } else {
         UsingStream = usingStream;
@@ -55,8 +55,8 @@ void TUserJobStatsProxy::InitChecked(IOutputStream* def) {
 
     if (usingStream == nullptr && !GetEnv("YT_JOB_ID").empty()) {
         TFileHandle fixedDesrc(JobStatisticsHandle);
-        FetchedOut = MakeHolder<TFixedBufferFileOutput>(TFile(fixedDesrc.Duplicate()));
-        UsingStream = FetchedOut.Get();
+        FetchedOut = std::make_unique<TFixedBufferFileOutput>(TFile(fixedDesrc.Duplicate()));
+        UsingStream = FetchedOut.get();
         fixedDesrc.Release();
     } else {
         UsingStream = def;
@@ -89,7 +89,7 @@ void TUserJobStatsProxy::CommitStats() {
 
 
 TTimeStatHolder TUserJobStatsProxy::TimerStart(TString name, bool commitOnFinish) {
-    return THolder(new TTimeStat(this, name, commitOnFinish));
+    return std::unique_ptr<TTimeStat>(new TTimeStat(this, name, commitOnFinish));
 }
 
 void TUserJobStatsProxy::WriteStat(TString name, i64 val) {
diff --git a/yt/cpp/mapreduce/library/user_job_statistics/user_job_statistics.h b/yt/cpp/mapreduce/library/user_job_statistics/user_job_statistics.h
index 6939d20417..928c79864b 100644
--- a/yt/cpp/mapreduce/library/user_job_statistics/user_job_statistics.h
+++ b/yt/cpp/mapreduce/library/user_job_statistics/user_job_statistics.h
@@ -6,13 +6,13 @@
 
 namespace NYtTools {
     class TTimeStat;
-    using TTimeStatHolder = THolder<TTimeStat>;
+    using TTimeStatHolder = std::unique_ptr<TTimeStat>;
 
     class TUserJobStatsProxy {
     public:
         static const FHANDLE JobStatisticsHandle;
     private:
-        THolder<IOutputStream> FetchedOut;
+        std::unique_ptr<IOutputStream> FetchedOut;
         IOutputStream* UsingStream = &Cerr;
     public:
         // TODO: add inheritance
diff --git a/yt/cpp/mapreduce/raw_client/raw_client.cpp b/yt/cpp/mapreduce/raw_client/raw_client.cpp
index 65bfa01cea..2868e10f6e 100644
--- a/yt/cpp/mapreduce/raw_client/raw_client.cpp
+++ b/yt/cpp/mapreduce/raw_client/raw_client.cpp
@@ -289,6 +289,18 @@ void THttpRawClient::CommitTransaction(
     RequestWithoutRetry(Context_, mutationId, header)->GetResponse();
 }
 
+TOperationId THttpRawClient::StartOperation(
+    TMutationId& mutationId,
+    const TTransactionId& transactionId,
+    EOperationType type,
+    const TNode& spec)
+{
+    THttpHeader header("POST", "start_op");
+    header.AddMutationId();
+    header.MergeParameters(NRawClient::SerializeParamsForStartOperation(transactionId, type, spec));
+    return ParseGuidFromResponse(RequestWithoutRetry(Context_, mutationId, header)->GetResponse());
+}
+
 TOperationAttributes THttpRawClient::GetOperation(
     const TOperationId& operationId,
     const TGetOperationOptions& options)
diff --git a/yt/cpp/mapreduce/raw_client/raw_client.h b/yt/cpp/mapreduce/raw_client/raw_client.h
index e540d1b331..1b3e274507 100644
--- a/yt/cpp/mapreduce/raw_client/raw_client.h
+++ b/yt/cpp/mapreduce/raw_client/raw_client.h
@@ -136,6 +136,12 @@ public:
 
     // Operations
 
+    TOperationId StartOperation(
+        TMutationId& mutationId,
+        const TTransactionId& transactionId,
+        EOperationType type,
+        const TNode& spec) override;
+
     TOperationAttributes GetOperation(
         const TOperationId& operationId,
         const TGetOperationOptions& options = {}) override;
diff --git a/yt/cpp/mapreduce/raw_client/rpc_parameters_serialization.cpp b/yt/cpp/mapreduce/raw_client/rpc_parameters_serialization.cpp
index 2869ddcc0f..98ef5ed099 100644
--- a/yt/cpp/mapreduce/raw_client/rpc_parameters_serialization.cpp
+++ b/yt/cpp/mapreduce/raw_client/rpc_parameters_serialization.cpp
@@ -393,7 +393,21 @@ TNode SerializeParamsForListOperations(
     return result;
 }
 
-TNode SerializeParamsForGetOperation(const std::variant<TString, TOperationId>& aliasOrOperationId, const TGetOperationOptions& options)
+TNode SerializeParamsForStartOperation(
+    const TTransactionId& transactionId,
+    EOperationType type,
+    const TNode& spec)
+{
+    TNode result;
+    SetTransactionIdParam(&result, transactionId);
+    result["operation_type"] = ToString(type);
+    result["spec"] = spec;
+    return result;
+}
+
+TNode SerializeParamsForGetOperation(
+    const std::variant<TString, TOperationId>& aliasOrOperationId,
+    const TGetOperationOptions& options)
 {
     auto includeRuntime = options.IncludeRuntime_;
     TNode result;
diff --git a/yt/cpp/mapreduce/raw_client/rpc_parameters_serialization.h b/yt/cpp/mapreduce/raw_client/rpc_parameters_serialization.h
index acbf003b5c..308dcfea64 100644
--- a/yt/cpp/mapreduce/raw_client/rpc_parameters_serialization.h
+++ b/yt/cpp/mapreduce/raw_client/rpc_parameters_serialization.h
@@ -1,8 +1,10 @@
 #pragma once
 
 #include <yt/cpp/mapreduce/common/helpers.h>
-#include <yt/cpp/mapreduce/interface/fwd.h>
+
 #include <yt/cpp/mapreduce/interface/client_method_options.h>
+#include <yt/cpp/mapreduce/interface/fwd.h>
+#include <yt/cpp/mapreduce/interface/operation.h>
 
 namespace NYT::NDetail::NRawClient {
 
@@ -95,7 +97,14 @@ TNode SerializeParamsForConcatenate(
 TNode SerializeParamsForPingTx(
     const TTransactionId& transactionId);
 
-TNode SerializeParamsForGetOperation(const std::variant<TString, TOperationId>& aliasOrOperationId, const TGetOperationOptions& options);
+TNode SerializeParamsForStartOperation(
+    const TTransactionId& transactionId,
+    EOperationType type,
+    const TNode& spec);
+
+TNode SerializeParamsForGetOperation(
+    const std::variant<TString, TOperationId>& aliasOrOperationId,
+    const TGetOperationOptions& options);
 
 TNode SerializeParamsForAbortOperation(
     const TOperationId& operationId);