diff --git a/tdactor/td/actor/impl/ConcurrentScheduler.cpp b/tdactor/td/actor/impl/ConcurrentScheduler.cpp
index 46a726975..167402a52 100644
--- a/tdactor/td/actor/impl/ConcurrentScheduler.cpp
+++ b/tdactor/td/actor/impl/ConcurrentScheduler.cpp
@@ -14,10 +14,6 @@
 #include "td/utils/MpscPollableQueue.h"
 #include "td/utils/port/thread_local.h"
 
-#if TD_PORT_WINDOWS
-#include "td/utils/port/detail/WineventPoll.h"
-#endif
-
 #include <memory>
 
 namespace td {
@@ -61,7 +57,7 @@ void ConcurrentScheduler::init(int32 threads_n) {
   }
 
 #if TD_PORT_WINDOWS
-  iocp_ = std::make_unique<detail::IOCP>();
+  iocp_ = std::make_unique<detail::Iocp>();
   iocp_->init();
 #endif
 
@@ -86,7 +82,7 @@ void ConcurrentScheduler::start() {
     threads_.push_back(td::thread([&, tid = i]() {
       set_thread_id(static_cast<int32>(tid));
 #if TD_PORT_WINDOWS
-      td::detail::IOCP::Guard iocp_guard(iocp_.get());
+      td::detail::Iocp::Guard iocp_guard(iocp_.get());
 #endif
       while (!is_finished()) {
         sched->run(10);
@@ -110,7 +106,7 @@ bool ConcurrentScheduler::run_main(double timeout) {
   auto &main_sched = schedulers_[0];
   if (!is_finished()) {
 #if TD_PORT_WINDOWS
-    td::detail::IOCP::Guard iocp_guard(iocp_.get());
+    td::detail::Iocp::Guard iocp_guard(iocp_.get());
 #endif
     main_sched->run(timeout);
   }
@@ -126,7 +122,7 @@ void ConcurrentScheduler::finish() {
   SCOPE_EXIT {
     iocp_->clear();
   };
-  td::detail::IOCP::Guard iocp_guard(iocp_.get());
+  td::detail::Iocp::Guard iocp_guard(iocp_.get());
 #endif
 
 #if !TD_THREAD_UNSUPPORTED && !TD_EVENTFD_UNSUPPORTED
diff --git a/tdactor/td/actor/impl/ConcurrentScheduler.h b/tdactor/td/actor/impl/ConcurrentScheduler.h
index 52c6c5ab4..f835badba 100644
--- a/tdactor/td/actor/impl/ConcurrentScheduler.h
+++ b/tdactor/td/actor/impl/ConcurrentScheduler.h
@@ -13,6 +13,10 @@
 #include "td/utils/port/thread.h"
 #include "td/utils/Slice.h"
 
+#if TD_PORT_WINDOWS
+#include "td/utils/port/detail/Iocp.h"
+#endif
+
 #include <atomic>
 #include <functional>
 #include <mutex>
@@ -20,12 +24,6 @@
 
 namespace td {
 
-#if TD_PORT_WINDOWS
-namespace detail {
-class IOCP;
-}
-#endif
-
 class ConcurrentScheduler : private Scheduler::Callback {
  public:
   void init(int32 threads_n);
@@ -87,7 +85,7 @@ class ConcurrentScheduler : private Scheduler::Callback {
   std::vector<thread> threads_;
 #endif
 #if TD_PORT_WINDOWS
-  std::unique_ptr<detail::IOCP> iocp_;
+  std::unique_ptr<detail::Iocp> iocp_;
   td::thread iocp_thread_;
 #endif
 
diff --git a/tdutils/CMakeLists.txt b/tdutils/CMakeLists.txt
index 414e3d3c5..c63175801 100644
--- a/tdutils/CMakeLists.txt
+++ b/tdutils/CMakeLists.txt
@@ -52,6 +52,7 @@ set(TDUTILS_SOURCE
   td/utils/port/detail/EventFdBsd.cpp
   td/utils/port/detail/EventFdLinux.cpp
   td/utils/port/detail/EventFdWindows.cpp
+  td/utils/port/detail/Iocp.cpp
   td/utils/port/detail/KQueue.cpp
   td/utils/port/detail/NativeFd.cpp
   td/utils/port/detail/Poll.cpp
@@ -117,6 +118,7 @@ set(TDUTILS_SOURCE
   td/utils/port/detail/EventFdBsd.h
   td/utils/port/detail/EventFdLinux.h
   td/utils/port/detail/EventFdWindows.h
+  td/utils/port/detail/Iocp.h
   td/utils/port/detail/KQueue.h
   td/utils/port/detail/NativeFd.h
   td/utils/port/detail/Poll.h
diff --git a/tdutils/td/utils/port/ServerSocketFd.cpp b/tdutils/td/utils/port/ServerSocketFd.cpp
index 66a405f94..712d983ec 100644
--- a/tdutils/td/utils/port/ServerSocketFd.cpp
+++ b/tdutils/td/utils/port/ServerSocketFd.cpp
@@ -25,7 +25,7 @@
 #endif
 
 #if TD_PORT_WINDOWS
-#include "td/utils/port/detail/WineventPoll.h"
+#include "td/utils/port/detail/Iocp.h"
 #include "td/utils/SpinLock.h"
 #include "td/utils/VectorQueue.h"
 #endif
@@ -37,11 +37,11 @@ namespace td {
 
 namespace detail {
 #if TD_PORT_WINDOWS
-class ServerSocketFdImpl : private IOCP::Callback {
+class ServerSocketFdImpl : private Iocp::Callback {
  public:
   ServerSocketFdImpl(NativeFd fd, int socket_family) : info_(std::move(fd)), socket_family_(socket_family) {
     VLOG(fd) << get_native_fd().socket() << " create ServerSocketFd";
-    IOCP::get()->subscribe(get_native_fd(), this);
+    Iocp::get()->subscribe(get_native_fd(), this);
     notify_iocp_read();
   }
   void close() {
@@ -185,11 +185,11 @@ class ServerSocketFdImpl : private IOCP::Callback {
   void notify_iocp_read() {
     VLOG(fd) << get_native_fd().socket() << " notify_read";
     inc_refcnt();
-    IOCP::get()->post(0, this, nullptr);
+    Iocp::get()->post(0, this, nullptr);
   }
   void notify_iocp_close() {
     VLOG(fd) << get_native_fd().socket() << " notify_close";
-    IOCP::get()->post(0, this, reinterpret_cast<WSAOVERLAPPED *>(&close_overlapped_));
+    Iocp::get()->post(0, this, reinterpret_cast<WSAOVERLAPPED *>(&close_overlapped_));
   }
 };
 void ServerSocketFdImplDeleter::operator()(ServerSocketFdImpl *impl) {
diff --git a/tdutils/td/utils/port/SocketFd.cpp b/tdutils/td/utils/port/SocketFd.cpp
index a52748a91..ecd7311a5 100644
--- a/tdutils/td/utils/port/SocketFd.cpp
+++ b/tdutils/td/utils/port/SocketFd.cpp
@@ -12,7 +12,7 @@
 
 #if TD_PORT_WINDOWS
 #include "td/utils/buffer.h"
-#include "td/utils/port/detail/WineventPoll.h"
+#include "td/utils/port/detail/Iocp.h"
 #include "td/utils/SpinLock.h"
 #include "td/utils/VectorQueue.h"
 #endif
@@ -33,12 +33,12 @@
 namespace td {
 namespace detail {
 #if TD_PORT_WINDOWS
-class SocketFdImpl : private IOCP::Callback {
+class SocketFdImpl : private Iocp::Callback {
  public:
   explicit SocketFdImpl(NativeFd native_fd) : info(std::move(native_fd)) {
     VLOG(fd) << get_native_fd().socket() << " create from native_fd";
     get_poll_info().add_flags(PollFlags::Write());
-    IOCP::get()->subscribe(get_native_fd(), this);
+    Iocp::get()->subscribe(get_native_fd(), this);
     is_read_active_ = true;
     notify_iocp_connected();
   }
@@ -46,7 +46,7 @@ class SocketFdImpl : private IOCP::Callback {
   SocketFdImpl(NativeFd native_fd, const IPAddress &addr) : info(std::move(native_fd)) {
     VLOG(fd) << get_native_fd().socket() << " create from native_fd and connect";
     get_poll_info().add_flags(PollFlags::Write());
-    IOCP::get()->subscribe(get_native_fd(), this);
+    Iocp::get()->subscribe(get_native_fd(), this);
     LPFN_CONNECTEX ConnectExPtr = nullptr;
     GUID guid = WSAID_CONNECTEX;
     DWORD numBytes;
@@ -294,14 +294,14 @@ class SocketFdImpl : private IOCP::Callback {
 
   void notify_iocp_write() {
     inc_refcnt();
-    IOCP::get()->post(0, this, nullptr);
+    Iocp::get()->post(0, this, nullptr);
   }
   void notify_iocp_close() {
-    IOCP::get()->post(0, this, reinterpret_cast<WSAOVERLAPPED *>(&close_overlapped_));
+    Iocp::get()->post(0, this, reinterpret_cast<WSAOVERLAPPED *>(&close_overlapped_));
   }
   void notify_iocp_connected() {
     inc_refcnt();
-    IOCP::get()->post(0, this, &read_overlapped_);
+    Iocp::get()->post(0, this, &read_overlapped_);
   }
 };
 
@@ -498,7 +498,8 @@ Result<SocketFd> SocketFd::open(const IPAddress &address) {
   TRY_STATUS(detail::init_socket_options(native_fd));
 
 #if TD_PORT_POSIX
-  int e_connect = connect(native_fd.socket(), address.get_sockaddr(), narrow_cast<socklen_t>(address.get_sockaddr_len()));
+  int e_connect =
+      connect(native_fd.socket(), address.get_sockaddr(), narrow_cast<socklen_t>(address.get_sockaddr_len()));
   if (e_connect == -1) {
     auto connect_errno = errno;
     if (connect_errno != EINPROGRESS) {
diff --git a/tdutils/td/utils/port/UdpSocketFd.cpp b/tdutils/td/utils/port/UdpSocketFd.cpp
index 4ec12bc35..d0fba9c63 100644
--- a/tdutils/td/utils/port/UdpSocketFd.cpp
+++ b/tdutils/td/utils/port/UdpSocketFd.cpp
@@ -15,7 +15,7 @@
 #include "td/utils/VectorQueue.h"
 
 #if TD_PORT_WINDOWS
-#include "td/utils/port/detail/WineventPoll.h"
+#include "td/utils/port/detail/Iocp.h"
 #include "td/utils/SpinLock.h"
 #endif
 
@@ -98,11 +98,11 @@ class UdpSocketSendHelper {
   WSABUF buf_;
 };
 
-class UdpSocketFdImpl : private IOCP::Callback {
+class UdpSocketFdImpl : private Iocp::Callback {
  public:
   explicit UdpSocketFdImpl(NativeFd fd) : info_(std::move(fd)) {
     get_poll_info().add_flags(PollFlags::Write());
-    IOCP::get()->subscribe(get_native_fd(), this);
+    Iocp::get()->subscribe(get_native_fd(), this);
     is_receive_active_ = true;
     notify_iocp_connected();
   }
@@ -339,14 +339,14 @@ class UdpSocketFdImpl : private IOCP::Callback {
 
   void notify_iocp_send() {
     inc_refcnt();
-    IOCP::get()->post(0, this, nullptr);
+    Iocp::get()->post(0, this, nullptr);
   }
   void notify_iocp_close() {
-    IOCP::get()->post(0, this, reinterpret_cast<WSAOVERLAPPED *>(&close_overlapped_));
+    Iocp::get()->post(0, this, reinterpret_cast<WSAOVERLAPPED *>(&close_overlapped_));
   }
   void notify_iocp_connected() {
     inc_refcnt();
-    IOCP::get()->post(0, this, reinterpret_cast<WSAOVERLAPPED *>(&receive_overlapped_));
+    Iocp::get()->post(0, this, reinterpret_cast<WSAOVERLAPPED *>(&receive_overlapped_));
   }
 };
 
diff --git a/tdutils/td/utils/port/detail/Iocp.cpp b/tdutils/td/utils/port/detail/Iocp.cpp
new file mode 100644
index 000000000..f651d54ea
--- /dev/null
+++ b/tdutils/td/utils/port/detail/Iocp.cpp
@@ -0,0 +1,87 @@
+//
+// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2018
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+#include "td/utils/port/detail/Iocp.h"
+
+char disable_linker_warning_about_empty_file_iocp_cpp TD_UNUSED;
+
+#ifdef TD_PORT_WINDOWS
+
+#include "td/utils/logging.h"
+
+namespace td {
+namespace detail {
+Iocp::~Iocp() {
+  clear();
+}
+
+void Iocp::loop() {
+  Iocp::Guard guard(this);
+  while (true) {
+    DWORD bytes = 0;
+    ULONG_PTR key = 0;
+    WSAOVERLAPPED *overlapped = nullptr;
+    BOOL ok =
+        GetQueuedCompletionStatus(iocp_handle_.fd(), &bytes, &key, reinterpret_cast<OVERLAPPED **>(&overlapped), 1000);
+    if (bytes || key || overlapped) {
+      // LOG(ERROR) << "Got IOCP " << bytes << " " << key << " " << overlapped;
+    }
+    if (ok) {
+      auto callback = reinterpret_cast<Iocp::Callback *>(key);
+      if (callback == nullptr) {
+        // LOG(ERROR) << "Interrupt IOCP loop";
+        return;
+      }
+      callback->on_iocp(bytes, overlapped);
+    } else {
+      if (overlapped != nullptr) {
+        auto error = OS_ERROR("Received from IOCP");
+        auto callback = reinterpret_cast<Iocp::Callback *>(key);
+        CHECK(callback != nullptr);
+        callback->on_iocp(std::move(error), overlapped);
+      }
+    }
+  }
+}
+
+void Iocp::interrupt_loop() {
+  post(0, nullptr, nullptr);
+}
+
+void Iocp::init() {
+  CHECK(!iocp_handle_);
+  auto res = CreateIoCompletionPort(INVALID_HANDLE_VALUE, nullptr, 0, 0);
+  if (res == nullptr) {
+    auto error = OS_ERROR("IOCP creation failed");
+    LOG(FATAL) << error;
+  }
+  iocp_handle_ = NativeFd(res);
+}
+
+void Iocp::clear() {
+  iocp_handle_.close();
+}
+
+void Iocp::subscribe(const NativeFd &native_fd, Callback *callback) {
+  CHECK(iocp_handle_);
+  auto iocp_handle =
+      CreateIoCompletionPort(native_fd.fd(), iocp_handle_.fd(), reinterpret_cast<ULONG_PTR>(callback), 0);
+  if (iocp_handle == INVALID_HANDLE_VALUE) {
+    auto error = OS_ERROR("CreateIoCompletionPort");
+    LOG(FATAL) << error;
+  }
+  CHECK(iocp_handle == iocp_handle_.fd()) << iocp_handle << " " << iocp_handle_.fd();
+}
+
+void Iocp::post(size_t size, Callback *callback, WSAOVERLAPPED *overlapped) {
+  PostQueuedCompletionStatus(iocp_handle_.fd(), DWORD(size), reinterpret_cast<ULONG_PTR>(callback),
+                             reinterpret_cast<OVERLAPPED *>(overlapped));
+}
+
+}  // namespace detail
+}  // namespace td
+
+#endif
diff --git a/tdutils/td/utils/port/detail/Iocp.h b/tdutils/td/utils/port/detail/Iocp.h
new file mode 100644
index 000000000..9c7caec4f
--- /dev/null
+++ b/tdutils/td/utils/port/detail/Iocp.h
@@ -0,0 +1,52 @@
+//
+// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2018
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+#pragma once
+
+#include "td/utils/port/config.h"
+
+#ifdef TD_PORT_WINDOWS
+
+#include "td/utils/common.h"
+#include "td/utils/Context.h"
+#include "td/utils/port/detail/NativeFd.h"
+#include "td/utils/port/thread.h"
+#include "td/utils/Status.h"
+
+namespace td {
+namespace detail {
+
+class Iocp final : public Context<Iocp> {
+ public:
+  Iocp() = default;
+  Iocp(const Iocp &) = delete;
+  Iocp &operator=(const Iocp &) = delete;
+  Iocp(Iocp &&) = delete;
+  Iocp &operator=(Iocp &&) = delete;
+  ~Iocp();
+
+  class Callback {
+   public:
+    virtual ~Callback() = default;
+    virtual void on_iocp(Result<size_t> r_size, WSAOVERLAPPED *overlapped) = 0;
+  };
+
+  void init();
+  void subscribe(const NativeFd &fd, Callback *callback);
+  void post(size_t size, Callback *callback, WSAOVERLAPPED *overlapped);
+  void loop();
+  void interrupt_loop();
+  void clear();
+
+ private:
+  NativeFd iocp_handle_;
+  std::vector<td::thread> workers_;
+};
+
+}  // namespace detail
+}  // namespace td
+
+#endif
diff --git a/tdutils/td/utils/port/detail/WineventPoll.cpp b/tdutils/td/utils/port/detail/WineventPoll.cpp
index e433b32f4..05be85cac 100644
--- a/tdutils/td/utils/port/detail/WineventPoll.cpp
+++ b/tdutils/td/utils/port/detail/WineventPoll.cpp
@@ -10,81 +10,10 @@ char disable_linker_warning_about_empty_file_wineventpoll_cpp TD_UNUSED;
 
 #ifdef TD_POLL_WINEVENT
 
-#include "td/utils/common.h"
 #include "td/utils/logging.h"
-#include "td/utils/port/PollBase.h"
-#include "td/utils/Status.h"
-
-#include <utility>
 
 namespace td {
 namespace detail {
-IOCP::~IOCP() {
-  clear();
-}
-
-void IOCP::loop() {
-  IOCP::Guard guard(this);
-  while (true) {
-    DWORD bytes = 0;
-    ULONG_PTR key = 0;
-    WSAOVERLAPPED *overlapped = nullptr;
-    BOOL ok =
-        GetQueuedCompletionStatus(iocp_handle_.fd(), &bytes, &key, reinterpret_cast<OVERLAPPED **>(&overlapped), 1000);
-    if (bytes || key || overlapped) {
-      // LOG(ERROR) << "Got IOCP " << bytes << " " << key << " " << overlapped;
-    }
-    if (ok) {
-      auto callback = reinterpret_cast<IOCP::Callback *>(key);
-      if (callback == nullptr) {
-        // LOG(ERROR) << "Interrupt IOCP loop";
-        return;
-      }
-      callback->on_iocp(bytes, overlapped);
-    } else {
-      if (overlapped != nullptr) {
-        auto error = OS_ERROR("Received from IOCP");
-        auto callback = reinterpret_cast<IOCP::Callback *>(key);
-        CHECK(callback != nullptr);
-        callback->on_iocp(std::move(error), overlapped);
-      }
-    }
-  }
-}
-
-void IOCP::interrupt_loop() {
-  post(0, nullptr, nullptr);
-}
-
-void IOCP::init() {
-  CHECK(!iocp_handle_);
-  auto res = CreateIoCompletionPort(INVALID_HANDLE_VALUE, nullptr, 0, 0);
-  if (res == nullptr) {
-    auto error = OS_ERROR("IOCP creation failed");
-    LOG(FATAL) << error;
-  }
-  iocp_handle_ = NativeFd(res);
-}
-
-void IOCP::clear() {
-  iocp_handle_.close();
-}
-
-void IOCP::subscribe(const NativeFd &native_fd, Callback *callback) {
-  CHECK(iocp_handle_);
-  auto iocp_handle =
-      CreateIoCompletionPort(native_fd.fd(), iocp_handle_.fd(), reinterpret_cast<ULONG_PTR>(callback), 0);
-  if (iocp_handle == INVALID_HANDLE_VALUE) {
-    auto error = OS_ERROR("CreateIoCompletionPort");
-    LOG(FATAL) << error;
-  }
-  CHECK(iocp_handle == iocp_handle_.fd()) << iocp_handle << " " << iocp_handle_.fd();
-}
-
-void IOCP::post(size_t size, Callback *callback, WSAOVERLAPPED *overlapped) {
-  PostQueuedCompletionStatus(iocp_handle_.fd(), DWORD(size), reinterpret_cast<ULONG_PTR>(callback),
-                             reinterpret_cast<OVERLAPPED *>(overlapped));
-}
 
 void WineventPoll::init() {
 }
diff --git a/tdutils/td/utils/port/detail/WineventPoll.h b/tdutils/td/utils/port/detail/WineventPoll.h
index 6213541aa..bc9bbd16e 100644
--- a/tdutils/td/utils/port/detail/WineventPoll.h
+++ b/tdutils/td/utils/port/detail/WineventPoll.h
@@ -11,44 +11,13 @@
 #ifdef TD_POLL_WINEVENT
 
 #include "td/utils/common.h"
-#include "td/utils/Context.h"
-#include "td/utils/port/detail/NativeFd.h"
 #include "td/utils/port/detail/PollableFd.h"
 #include "td/utils/port/PollBase.h"
 #include "td/utils/port/PollFlags.h"
-#include "td/utils/port/thread.h"
-#include "td/utils/Status.h"
 
 namespace td {
 namespace detail {
 
-class IOCP final : public Context<IOCP> {
- public:
-  IOCP() = default;
-  IOCP(const IOCP &) = delete;
-  IOCP &operator=(const IOCP &) = delete;
-  IOCP(IOCP &&) = delete;
-  IOCP &operator=(IOCP &&) = delete;
-  ~IOCP();
-
-  class Callback {
-   public:
-    virtual ~Callback() = default;
-    virtual void on_iocp(Result<size_t> r_size, WSAOVERLAPPED *overlapped) = 0;
-  };
-
-  void init();
-  void subscribe(const NativeFd &fd, Callback *callback);
-  void post(size_t size, Callback *callback, WSAOVERLAPPED *overlapped);
-  void loop();
-  void interrupt_loop();
-  void clear();
-
- private:
-  NativeFd iocp_handle_;
-  std::vector<td::thread> workers_;
-};
-
 class WineventPoll final : public PollBase {
  public:
   WineventPoll() = default;