diff --git a/Dockerfile b/Dockerfile
index 13c9e2b86..9086d880e 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -42,7 +42,7 @@ COPY . /opt
 ARG PROXY_REVISION
 ARG LOG_CFG=log_cfg.json
 RUN (cp -f /opt/${LOG_CFG} /opt/log_cfg.json || true)
-RUN sed -i 's/NEON_PROXY_REVISION_TO_BE_REPLACED/'"$PROXY_REVISION"'/g' /opt/proxy/neon_rpc_api_model/neon_rpc_api_model.py
+RUN sed -i 's/NEON_PROXY_REVISION_TO_BE_REPLACED/'"$PROXY_REVISION"'/g' /opt/proxy/neon_rpc_api_model/neon_rcp_api_worker.py
 
 COPY ./proxy/solana-py.patch /opt
 RUN cd /usr/local/lib/python3.8/dist-packages/ && patch -p0 </opt/solana-py.patch
diff --git a/proxy/common_neon/utils/__init__.py b/proxy/common_neon/utils/__init__.py
index 80779403d..3361c8947 100644
--- a/proxy/common_neon/utils/__init__.py
+++ b/proxy/common_neon/utils/__init__.py
@@ -1,5 +1,5 @@
 from .utils import *
 
-from .pickable_data_server import AddrPickableDataSrv, PipePickableDataSrv, PickableDataServerUser, \
+from .pickable_data_server import AddrPickableDataSrv, PipePickableDataSrv, IPickableDataServerUser, \
                                   AddrPickableDataClient, PipePickableDataClient
 
diff --git a/proxy/common_neon/utils/pickable_data_server.py b/proxy/common_neon/utils/pickable_data_server.py
index 5a54df3eb..7ba807dc5 100644
--- a/proxy/common_neon/utils/pickable_data_server.py
+++ b/proxy/common_neon/utils/pickable_data_server.py
@@ -9,7 +9,7 @@
 from logged_groups import logged_group
 
 
-class PickableDataServerUser(ABC):
+class IPickableDataServerUser(ABC):
 
     @abstractmethod
     async def on_data_received(self, data: Any) -> Any:
@@ -25,7 +25,7 @@ def encode_pickable(object) -> bytes:
 @logged_group("neon.MemPool")
 class PickableDataServer(ABC):
 
-    def __init__(self, *, user: PickableDataServerUser):
+    def __init__(self, *, user: IPickableDataServerUser):
         self._user = user
         asyncio.get_event_loop().create_task(self.run_server())
 
@@ -63,7 +63,7 @@ async def _recv_pickable_data(self, reader: StreamReader):
 
 class AddrPickableDataSrv(PickableDataServer):
 
-    def __init__(self, *, user: PickableDataServerUser, address: Tuple[str, int]):
+    def __init__(self, *, user: IPickableDataServerUser, address: Tuple[str, int]):
         self._address = address
         PickableDataServer.__init__(self, user=user)
 
@@ -75,7 +75,7 @@ async def run_server(self):
 
 class PipePickableDataSrv(PickableDataServer):
 
-    def __init__(self, *, user: PickableDataServerUser, srv_sock: socket.socket):
+    def __init__(self, *, user: IPickableDataServerUser, srv_sock: socket.socket):
         self._srv_sock = srv_sock
         PickableDataServer.__init__(self, user=user)
 
diff --git a/proxy/mempool/executor_mng.py b/proxy/mempool/executor_mng.py
index 91bac4898..4d2a5252b 100644
--- a/proxy/mempool/executor_mng.py
+++ b/proxy/mempool/executor_mng.py
@@ -13,7 +13,7 @@
 from .mempool_executor import MPExecutor
 
 
-class MpExecutorClient(PipePickableDataClient):
+class MPExecutorClient(PipePickableDataClient):
 
     def __init__(self, client_sock: socket.socket):
         PipePickableDataClient.__init__(self, client_sock=client_sock)
@@ -30,7 +30,7 @@ class MPExecutorMng(IMPExecutor):
     @dataclasses.dataclass
     class ExecutorInfo:
         executor: MPExecutor
-        client: MpExecutorClient
+        client: MPExecutorClient
         id: int
 
     def __init__(self, executor_count: int, config: IConfig):
@@ -57,7 +57,7 @@ def is_available(self) -> bool:
     def _has_available(self) -> bool:
         return len(self._available_executor_pool) > 0
 
-    def _get_executor(self) -> Tuple[int, MpExecutorClient]:
+    def _get_executor(self) -> Tuple[int, MPExecutorClient]:
         executor_id = self._available_executor_pool.pop()
         self.debug(f"Acquire executor: {executor_id}")
         self._busy_executor_pool.add(executor_id)
@@ -81,7 +81,7 @@ def release_resource(self, resource_id: int):
     def _create_executor(executor_id: int, config: IConfig) -> ExecutorInfo:
         client_sock, srv_sock = socket.socketpair()
         executor = MPExecutor(executor_id, srv_sock, config)
-        client = MpExecutorClient(client_sock)
+        client = MPExecutorClient(client_sock)
         return MPExecutorMng.ExecutorInfo(executor=executor, client=client, id=executor_id)
 
     def __del__(self):
diff --git a/proxy/mempool/mempool.py b/proxy/mempool/mempool.py
index 9986d262a..1e245d2b6 100644
--- a/proxy/mempool/mempool.py
+++ b/proxy/mempool/mempool.py
@@ -3,7 +3,7 @@
 from logged_groups import logged_group
 import bisect
 
-from .mempool_api import MPRequest, MPResultCode, MPResult, IMPExecutor, MPRequestType, \
+from .mempool_api import MPRequest, MPResultCode, MPTxResult, IMPExecutor, MPRequestType, \
                          MPTxRequest, MPPendingTxCountReq
 
 
@@ -16,7 +16,6 @@ class MemPool:
 
     def __init__(self, executor: IMPExecutor):
         self._req_queue = []
-        self._lock = asyncio.Lock()
         self._req_queue_cond = asyncio.Condition()
         self._processing_tasks: List[Tuple[int, asyncio.Task, MPRequest]] = []
         # signer -> pending_tx_counter
@@ -29,12 +28,12 @@ def __init__(self, executor: IMPExecutor):
     async def enqueue_mp_request(self, mp_request: MPRequest):
         if mp_request.type == MPRequestType.SendTransaction:
             tx_request: MPTxRequest = mp_request
-            return await self.on_send_tx_request(tx_request)
+            return await self._on_send_tx_request(tx_request)
         elif mp_request.type == MPRequestType.GetTrxCount:
             pending_count_req: MPPendingTxCountReq = mp_request
             return self.get_pending_trx_count(pending_count_req.sender)
 
-    async def on_send_tx_request(self, mp_request: MPTxRequest):
+    async def _on_send_tx_request(self, mp_request: MPTxRequest):
         await self.enqueue_mp_transaction(mp_request)
         sender = "0x" + mp_request.neon_tx.sender()
         self._inc_pending_tx_counter(sender)
@@ -89,33 +88,33 @@ async def check_processing_tasks(self):
                     self._executor.release_resource(resource_id)
                     continue
 
-                mp_result: MPResult = task.result()
-                assert isinstance(mp_result, MPResult)
-                assert mp_result.code != MPResultCode.Dummy
-                await self._process_mp_result(resource_id, mp_result, mp_request)
+                mp_tx_result: MPTxResult = task.result()
+                assert isinstance(mp_tx_result, MPTxResult)
+                assert mp_tx_result.code != MPResultCode.Dummy
+                await self._process_mp_result(resource_id, mp_tx_result, mp_request)
 
             self._processing_tasks = not_finished_tasks
             await asyncio.sleep(MemPool.CHECK_TASK_TIMEOUT_SEC)
 
-    async def _process_mp_result(self, resource_id: int, mp_result: MPResult, mp_request: MPTxRequest):
+    async def _process_mp_result(self, resource_id: int, mp_tx_result: MPTxResult, mp_request: MPTxRequest):
         tx_hash = "0x" + mp_request.neon_tx.hash_signed().hex()
         log_ctx = {"context": {"req_id": mp_request.req_id}}
-        if mp_result.code == MPResultCode.Done:
+        if mp_tx_result.code == MPResultCode.Done:
             self.debug(f"Neon tx: {tx_hash} - processed on executor: {resource_id} - done", extra=log_ctx)
             self._on_request_done(mp_request)
             self._executor.release_resource(resource_id)
             await self._kick_tx_queue()
             return
-        self.warning(f"Failed to process tx: {tx_hash} - on executor: {resource_id}, status: {mp_result} - reschedule", extra=log_ctx)
-        if mp_result.code == MPResultCode.BlockedAccount:
+        self.warning(f"Failed to process tx: {tx_hash} - on executor: {resource_id}, status: {mp_tx_result} - reschedule", extra=log_ctx)
+        if mp_tx_result.code == MPResultCode.BlockedAccount:
             self._executor.release_resource(resource_id)
             await self.enqueue_mp_request(mp_request)
             await self._kick_tx_queue()
-        elif mp_result.code == MPResultCode.NoLiquidity:
+        elif mp_tx_result.code == MPResultCode.NoLiquidity:
             self._executor.on_no_liquidity(resource_id)
             await self.enqueue_mp_request(mp_request)
             await self._kick_tx_queue()
-        elif mp_result.code == MPResultCode.Unspecified:
+        elif mp_tx_result.code == MPResultCode.Unspecified:
             self._executor.release_resource(resource_id)
             self._on_request_dropped_away(mp_request)
             await self._kick_tx_queue()
diff --git a/proxy/mempool/mempool_api.py b/proxy/mempool/mempool_api.py
index bc5dc3226..46274b016 100644
--- a/proxy/mempool/mempool_api.py
+++ b/proxy/mempool/mempool_api.py
@@ -73,6 +73,6 @@ class MPResultCode(IntEnum):
 
 
 @dataclass
-class MPResult:
+class MPTxResult:
     code: MPResultCode
     data: Any
diff --git a/proxy/mempool/mempool_executor.py b/proxy/mempool/mempool_executor.py
index 127ee4b02..91a86a33f 100644
--- a/proxy/mempool/mempool_executor.py
+++ b/proxy/mempool/mempool_executor.py
@@ -6,17 +6,17 @@
 
 from ..common_neon.solana_interactor import SolanaInteractor
 from ..common_neon.config import IConfig
-from ..common_neon.utils import PipePickableDataSrv, PickableDataServerUser, Any
+from ..common_neon.utils import PipePickableDataSrv, IPickableDataServerUser, Any
 from ..common_neon.config import Config
 from ..memdb.memdb import MemDB
 
 from .transaction_sender import NeonTxSender
 from .operator_resource_list import OperatorResourceList
-from .mempool_api import MPRequest, MPResult, MPResultCode
+from .mempool_api import MPRequest, MPTxResult, MPResultCode
 
 
 @logged_group("neon.MemPool")
-class MPExecutor(mp.Process, PickableDataServerUser):
+class MPExecutor(mp.Process, IPickableDataServerUser):
 
     def __init__(self, executor_id: int, srv_sock: socket.socket, config: IConfig):
         self.info(f"Initialize mempool_executor: {executor_id}")
@@ -44,8 +44,8 @@ def execute_neon_tx(self, mempool_request: MPRequest):
                 self.execute_neon_tx_impl(mempool_request)
             except Exception as err:
                 self.error(f"Failed to execute neon_tx: {err}")
-                return MPResult(MPResultCode.Unspecified, None)
-            return MPResult(MPResultCode.Done, None)
+                return MPTxResult(MPResultCode.Unspecified, None)
+            return MPTxResult(MPResultCode.Done, None)
 
     def execute_neon_tx_impl(self, mempool_tx_cfg: MPRequest):
         neon_tx = mempool_tx_cfg.neon_tx
diff --git a/proxy/mempool/mempool_service.py b/proxy/mempool/mempool_service.py
index 8478cfd9f..35e6c1131 100644
--- a/proxy/mempool/mempool_service.py
+++ b/proxy/mempool/mempool_service.py
@@ -3,7 +3,7 @@
 from multiprocessing import Process
 from typing import Any
 
-from ..common_neon.utils.pickable_data_server import AddrPickableDataSrv, PickableDataServerUser
+from ..common_neon.utils.pickable_data_server import AddrPickableDataSrv, IPickableDataServerUser
 from ..common_neon.config import IConfig
 
 from .mempool import MemPool
@@ -11,7 +11,7 @@
 
 
 @logged_group("neon.MemPool")
-class MPService(PickableDataServerUser):
+class MPService(IPickableDataServerUser):
 
     MP_SERVICE_PORT = 9091
     MP_SERVICE_HOST = "0.0.0.0"
diff --git a/proxy/neon_rpc_api_model/__init__.py b/proxy/neon_rpc_api_model/__init__.py
index 16b7421f3..059398e7d 100644
--- a/proxy/neon_rpc_api_model/__init__.py
+++ b/proxy/neon_rpc_api_model/__init__.py
@@ -1 +1 @@
-from . neon_rpc_api_model import NeonRpcApiModel, NEON_PROXY_PKG_VERSION, NEON_PROXY_REVISION
+from . neon_rcp_api_worker import NeonRpcApiWorker, NEON_PROXY_PKG_VERSION, NEON_PROXY_REVISION
diff --git a/proxy/neon_rpc_api_model/neon_rpc_api_model.py b/proxy/neon_rpc_api_model/neon_rcp_api_worker.py
similarity index 99%
rename from proxy/neon_rpc_api_model/neon_rpc_api_model.py
rename to proxy/neon_rpc_api_model/neon_rcp_api_worker.py
index 85ff17d6c..d408cb0e1 100644
--- a/proxy/neon_rpc_api_model/neon_rpc_api_model.py
+++ b/proxy/neon_rpc_api_model/neon_rcp_api_worker.py
@@ -42,7 +42,7 @@ def default(self, obj):
 
 
 @logged_group("neon.Proxy")
-class NeonRpcApiModel:
+class NeonRpcApiWorker:
     proxy_id_glob = multiprocessing.Value('i', 0)
 
     def __init__(self):
diff --git a/proxy/neon_rpc_api_model/transaction_validator.py b/proxy/neon_rpc_api_model/transaction_validator.py
index 90cc3228d..c4833efc6 100644
--- a/proxy/neon_rpc_api_model/transaction_validator.py
+++ b/proxy/neon_rpc_api_model/transaction_validator.py
@@ -80,11 +80,11 @@ def _prevalidate_tx(self):
         self._prevalidate_tx_chain_id()
         self._prevalidate_tx_size()
         self._prevalidate_sender_balance()
+        self._prevalidate_underpriced_tx_without_chainid()
 
     def _prevalidate_emulator(self, emulator_json: dict):
         self._prevalidate_gas_usage(emulator_json)
         self._prevalidate_account_sizes(emulator_json)
-        self._prevalidate_underpriced_tx_without_chainid()
 
     def extract_ethereum_error(self, e: Exception):
         receipt_parser = SolReceiptParser(e)
diff --git a/proxy/plugin/neon_rpc_api_plugin.py b/proxy/plugin/neon_rpc_api_plugin.py
index c7b3083b7..31d88306c 100644
--- a/proxy/plugin/neon_rpc_api_plugin.py
+++ b/proxy/plugin/neon_rpc_api_plugin.py
@@ -25,7 +25,7 @@
 from ..common_neon.solana_receipt_parser import SolTxError
 from ..common_neon.errors import EthereumError
 from ..environment import ENABLE_PRIVATE_API
-from ..neon_rpc_api_model import NeonRpcApiModel
+from ..neon_rpc_api_model import NeonRpcApiWorker
 from ..statistics_exporter.prometheus_proxy_exporter import PrometheusExporter
 
 modelInstanceLock = threading.Lock()
@@ -54,7 +54,7 @@ def getModel(cls):
         global modelInstance
         with modelInstanceLock:
             if modelInstance is None:
-                modelInstance = NeonRpcApiModel()
+                modelInstance = NeonRpcApiWorker()
             return modelInstance
 
     def routes(self) -> List[Tuple[int, str]]:
diff --git a/proxy/testing/test_neon_rpc_api.py b/proxy/testing/test_neon_rpc_api.py
index ee4342af7..ebc9c5dc3 100644
--- a/proxy/testing/test_neon_rpc_api.py
+++ b/proxy/testing/test_neon_rpc_api.py
@@ -1,13 +1,13 @@
 import unittest
 from logged_groups import logged_group
-from ..neon_rpc_api_model import NeonRpcApiModel
+from ..neon_rpc_api_model import NeonRpcApiWorker
 
 
 @logged_group("neon.TestCases")
 class SolanaContractTests(unittest.TestCase):
 
     def setUp(self):
-        self.model = NeonRpcApiModel()
+        self.model = NeonRpcApiWorker()
         self.owner = '0xc1566af4699928fdf9be097ca3dc47ece39f8f8e'
         self.token1 = '0x49a449cd7fd8fbcf34d103d98f2c05245020e35b'