diff --git a/lib/isc/Makefile.in b/lib/isc/Makefile.in
index 906ebd3e69..a8986c5a45 100644
--- a/lib/isc/Makefile.in
+++ b/lib/isc/Makefile.in
@@ -55,7 +55,7 @@ OBJS =		pk11.@O@ pk11_result.@O@ \
 		lex.@O@ lfsr.@O@ lib.@O@ log.@O@ \
 		md.@O@ mem.@O@ mutexblock.@O@ \
 		netmgr/netmgr.@O@ netmgr/tcp.@O@ netmgr/udp.@O@ \
-		netmgr/tcpdns.@O@ netmgr/uverr2result.@O@ \
+		netmgr/tcpdns.@O@ netmgr/uverr2result.@O@ netmgr/uv-compat.@O@ \
 		netaddr.@O@ netscope.@O@ nonce.@O@ openssl_shim.@O@ pool.@O@ \
 		parseint.@O@ portset.@O@ queue.@O@ quota.@O@ \
 		radix.@O@ random.@O@ ratelimiter.@O@ \
diff --git a/lib/isc/netmgr/Makefile.in b/lib/isc/netmgr/Makefile.in
index 74f0439521..f58caf5071 100644
--- a/lib/isc/netmgr/Makefile.in
+++ b/lib/isc/netmgr/Makefile.in
@@ -25,10 +25,10 @@ CDEFINES =
 CWARNINGS =
 
 # Alphabetically
-OBJS =		netmgr.@O@ tcp.@O@ udp.@O@ tcpdns.@O@ uverr2result.@O@
+OBJS =		netmgr.@O@ tcp.@O@ udp.@O@ tcpdns.@O@ uverr2result.@O@ uv-compat.@O@
 
 # Alphabetically
-SRCS =		netmgr.c tcp.c udp.c tcpdns.c uverr2result.c
+SRCS =		netmgr.c tcp.c udp.c tcpdns.c uverr2result.c uv-compat.c
 
 TARGETS =	${OBJS}
 
diff --git a/lib/isc/netmgr/uv-compat.c b/lib/isc/netmgr/uv-compat.c
new file mode 100644
index 0000000000..101c3c7201
--- /dev/null
+++ b/lib/isc/netmgr/uv-compat.c
@@ -0,0 +1,168 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#include <unistd.h>
+#include "uv-compat.h"
+
+/*
+ * XXXWPK: This code goes into libuv internals and it's platform dependent.
+ * It's ugly, we shouldn't do it, but the alternative with passing sockets
+ * over IPC sockets is even worse, and causes all kind of different
+ * problems. We should try to push these things upstream.
+ */
+
+#ifdef WIN32
+/* This code is adapted from libuv/src/win/internal.h */
+typedef enum {
+	UV__IPC_SOCKET_XFER_NONE = 0,
+	UV__IPC_SOCKET_XFER_TCP_CONNECTION,
+	UV__IPC_SOCKET_XFER_TCP_SERVER
+} uv__ipc_socket_xfer_type_t;
+
+typedef struct {
+	WSAPROTOCOL_INFOW socket_info;
+	uint32_t delayed_error;
+} uv__ipc_socket_xfer_info_t;
+
+int
+uv__tcp_xfer_import(uv_tcp_t *tcp, uv__ipc_socket_xfer_type_t xfer_type,
+		    uv__ipc_socket_xfer_info_t *xfer_info);
+int
+uv__tcp_xfer_export(uv_tcp_t *handle, int pid,
+		    uv__ipc_socket_xfer_info_t *xfer_info);
+
+int
+isc_uv_export(uv_stream_t *stream, isc_uv_stream_info_t *info) {
+	if (stream->type != UV_TCP) {
+		return (-1);
+	}
+	if (uv__tcp_xfer_export((uv_tcp_t *) stream, GetCurrentProcessId(),
+				&info->socket_info) == -1) {
+		return (-1);
+	}
+
+	info->type = UV_TCP;
+}
+
+int
+isc_uv_import(uv_stream_t *stream, isc_uv_stream_info_t *info) {
+	uv__ipc_socket_xfer_info_t xfer_info;
+
+	if (stream->type != UV_TCP || info->type != UV_TCP) {
+		return (-1);
+	}
+	xfer_info.socket_info = info->socket_info;
+
+	return (uv__tcp_xfer_import((uv_tcp_t *) stream,
+				    UV__IPC_SOCKET_XFER_TCP_SERVER,
+				    &xfer_info));
+}
+#else /* WIN32 */
+/* Adapted from libuv/src/unix/internal.h */
+#include <sys/ioctl.h>
+#include <fcntl.h>
+
+static int
+isc_uv__cloexec(int fd, int set) {
+	int r;
+
+	/*
+	 * This #ifdef is taken directly from the libuv sources.
+	 * We use FIOCLEX and FIONCLEX ioctl() calls when possible,
+	 * but on some platforms are not implemented, or defined but
+	 * not implemented correctly. On those, we use the FD_CLOEXEC
+	 * fcntl() call, which adds extra system call overhead, but
+	 * works.
+	 */
+#if defined(_AIX) || \
+    defined(__APPLE__) || \
+    defined(__DragonFly__) || \
+    defined(__FreeBSD__) || \
+    defined(__FreeBSD_kernel__) || \
+    defined(__linux__) || \
+    defined(__OpenBSD__) || \
+    defined(__NetBSD__)
+	do {
+		r = ioctl(fd, set ? FIOCLEX : FIONCLEX);
+	} while (r == -1 && errno == EINTR);
+#else /* FIOCLEX/FIONCLEX unsupported */
+	int flags;
+
+	do {
+		r = fcntl(fd, F_GETFD);
+	} while (r == -1 && errno == EINTR);
+
+	if (r == -1) {
+		return (-1);
+	}
+
+	if (!!(r & FD_CLOEXEC) == !!set) {
+		return (0);
+	}
+
+	if (set) {
+		flags = r | FD_CLOEXEC;
+	} else {
+		flags = r & ~FD_CLOEXEC;
+	}
+
+	do {
+		r = fcntl(fd, F_SETFD, flags);
+	} while (r == -1 && errno == EINTR);
+#endif /* FIOCLEX/FIONCLEX unsupported */
+
+	if (r != 0) {
+		return (-1);
+	}
+
+	return (0);
+}
+
+int
+isc_uv_export(uv_stream_t *stream, isc_uv_stream_info_t *info) {
+	int oldfd, fd;
+	int err;
+
+	if (stream->type != UV_TCP) {
+		return (-1);
+	}
+	err = uv_fileno((uv_handle_t *) stream, (uv_os_fd_t *) &oldfd);
+
+	if (err != 0) {
+		return (err);
+	}
+
+	fd = dup(oldfd);
+	if (fd == -1) {
+		return (-1);
+	}
+
+	err = isc_uv__cloexec(fd, 1);
+	if (err != 0) {
+		close(fd);
+		return (err);
+	}
+
+	info->type = stream->type;
+	info->fd = fd;
+	return (0);
+}
+
+int
+isc_uv_import(uv_stream_t *stream, isc_uv_stream_info_t *info) {
+	if (info->type != UV_TCP) {
+		return (-1);
+	}
+
+	uv_tcp_t *tcp = (uv_tcp_t *) stream;
+	return (uv_tcp_open(tcp, info->fd));
+}
+#endif
diff --git a/lib/isc/netmgr/uv-compat.h b/lib/isc/netmgr/uv-compat.h
index 6ec2f3237b..092c87976c 100644
--- a/lib/isc/netmgr/uv-compat.h
+++ b/lib/isc/netmgr/uv-compat.h
@@ -13,22 +13,59 @@
 #include <uv.h>
 
 /*
- * Those functions were introduced in newer libuv, we still
+ * These functions were introduced in newer libuv, but we still
  * want BIND9 compile on older ones so we emulate them.
  * They're inline to avoid conflicts when running with a newer
  * library version.
  */
 
 #ifndef HAVE_UV_HANDLE_GET_DATA
-static inline void*
-uv_handle_get_data(const uv_handle_t* handle) {
-    return (handle->data);
+static inline void *
+uv_handle_get_data(const uv_handle_t *handle) {
+	return (handle->data);
 }
 #endif
 
 #ifndef HAVE_UV_HANDLE_SET_DATA
 static inline void
-uv_handle_set_data(uv_handle_t* handle, void* data) {
-    handle->data = data;
+uv_handle_set_data(uv_handle_t *handle, void *data) {
+	handle->data = data;
 };
 #endif
+
+/*
+ * These functions are not available in libuv, but they're very internal
+ * to libuv. We should try to get them merged upstream.
+ */
+
+/*
+ * A sane way to pass listening TCP socket to child threads, without using
+ * IPC (as the libuv example shows) but a version of the uv_export() and
+ * uv_import() functions that were unfortunately removed from libuv.
+ * This is based on the original libuv code.
+ */
+
+typedef struct isc_uv_stream_info_s isc_uv_stream_info_t;
+
+struct isc_uv_stream_info_s {
+	uv_handle_type type;
+#ifdef WIN32
+	WSAPROTOCOL_INFOW socket_info;
+#else
+	int fd;
+#endif
+};
+
+int
+isc_uv_export(uv_stream_t *stream, isc_uv_stream_info_t *info);
+/*%<
+ * Exports uv_stream_t as isc_uv_stream_info_t value, which could
+ * be used to initialize shared streams within the same process.
+ */
+
+int
+isc_uv_import(uv_stream_t *stream, isc_uv_stream_info_t *info);
+/*%<
+ * Imports uv_stream_info_t value into uv_stream_t to initialize a
+ * shared stream.
+ */
diff --git a/lib/isc/win32/libisc.def.in b/lib/isc/win32/libisc.def.in
index fa20fe059d..618737983a 100644
--- a/lib/isc/win32/libisc.def.in
+++ b/lib/isc/win32/libisc.def.in
@@ -683,6 +683,8 @@ isc_timermgr_destroy
 isc_timermgr_poke
 isc_tm_timegm
 isc_tm_strptime
+isc_uv_export
+isc_uv_import
 isc_win32os_versioncheck
 openlog
 @IF PKCS11
diff --git a/lib/isc/win32/libisc.vcxproj.in b/lib/isc/win32/libisc.vcxproj.in
index e41b625e3a..9fd2d149fe 100644
--- a/lib/isc/win32/libisc.vcxproj.in
+++ b/lib/isc/win32/libisc.vcxproj.in
@@ -446,6 +446,7 @@ copy InstallFiles ..\Build\Release\
     <ClCompile Include="..\netmgr\tcp.c" />
     <ClCompile Include="..\netmgr\udp.c" />
     <ClCompile Include="..\netmgr\uverr2result.c" />
+    <ClCompile Include="..\netmgr\uv-compat.c" />
     <ClCompile Include="..\netmgr\tcpdns.c" />
     <ClCompile Include="..\netscope.c" />
     <ClCompile Include="..\nonce.c" />
diff --git a/util/copyrights b/util/copyrights
index a675fce20b..d15bd6424f 100644
--- a/util/copyrights
+++ b/util/copyrights
@@ -2257,6 +2257,7 @@
 ./lib/isc/netmgr/tcp.c				C	2019,2020
 ./lib/isc/netmgr/tcpdns.c			C	2019,2020
 ./lib/isc/netmgr/udp.c				C	2019,2020
+./lib/isc/netmgr/uv-compat.c			C	2020
 ./lib/isc/netmgr/uv-compat.h			C	2019,2020
 ./lib/isc/netmgr/uverr2result.c			C	2019,2020
 ./lib/isc/netscope.c				C	2002,2004,2005,2006,2007,2016,2018,2019,2020
@@ -2604,3 +2605,4 @@
 ./win32utils/GeoIP.diff				X	2013,2018,2019,2020
 ./win32utils/bind9.sln.in			X	2013,2014,2015,2016,2017,2018,2019,2020
 ./win32utils/index.html				HTML	2006,2007,2008,2012,2013,2014,2015,2016,2018,2019,2020
+./win32utils/libuv.diff				X	2020
diff --git a/win32utils/libuv.diff b/win32utils/libuv.diff
new file mode 100644
index 0000000000..41f3796ccc
--- /dev/null
+++ b/win32utils/libuv.diff
@@ -0,0 +1,27 @@
+To make TCP listening properly multithreaded, we need to have the
+uv_export() and uv_import() functions that were removed from libuv.
+The alternative is passing sockets over IPC, which is complicated and
+error prone.
+
+To make it simple, we export two internal functions from libuv; they will
+be used in lib/isc/netmgr/uv-compat.c by our versions of the uv_export()
+and uv_import() functions.
+
+diff --git a/src/win/internal.h b/src/win/internal.h
+index 058ddb8e..a9dc4168 100644
+--- a/src/win/internal.h
++++ b/src/win/internal.h
+@@ -92,11 +92,11 @@ void uv_process_tcp_connect_req(uv_loop_t* loop, uv_tcp_t* handle,
+ void uv_tcp_close(uv_loop_t* loop, uv_tcp_t* tcp);
+ void uv_tcp_endgame(uv_loop_t* loop, uv_tcp_t* handle);
+ 
+-int uv__tcp_xfer_export(uv_tcp_t* handle,
++UV_EXTERN int uv__tcp_xfer_export(uv_tcp_t* handle,
+                         int pid,
+                         uv__ipc_socket_xfer_type_t* xfer_type,
+                         uv__ipc_socket_xfer_info_t* xfer_info);
+-int uv__tcp_xfer_import(uv_tcp_t* tcp,
++UV_EXTERN int uv__tcp_xfer_import(uv_tcp_t* tcp,
+                         uv__ipc_socket_xfer_type_t xfer_type,
+                         uv__ipc_socket_xfer_info_t* xfer_info);
+