diff --git a/mcrouter/test/MCProcess.py b/mcrouter/test/MCProcess.py
index cb8501cfa..c9a2d909c 100644
--- a/mcrouter/test/MCProcess.py
+++ b/mcrouter/test/MCProcess.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import errno
 import os
diff --git a/mcrouter/test/McrouterTestCase.py b/mcrouter/test/McrouterTestCase.py
index 76a2d8f6c..1d74179fb 100644
--- a/mcrouter/test/McrouterTestCase.py
+++ b/mcrouter/test/McrouterTestCase.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import os
 import time
 import unittest
diff --git a/mcrouter/test/mock_servers.py b/mcrouter/test/mock_servers.py
index 90e19acce..10028cb9f 100644
--- a/mcrouter/test/mock_servers.py
+++ b/mcrouter/test/mock_servers.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import errno
 import socket
diff --git a/mcrouter/test/test_additional_fields.py b/mcrouter/test/test_additional_fields.py
index 222cc265d..81621547c 100644
--- a/mcrouter/test/test_additional_fields.py
+++ b/mcrouter/test/test_additional_fields.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_allow_only_gets.py b/mcrouter/test/test_allow_only_gets.py
index e8cee7020..83fed1d3a 100644
--- a/mcrouter/test/test_allow_only_gets.py
+++ b/mcrouter/test/test_allow_only_gets.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Memcached
diff --git a/mcrouter/test/test_ascii_error.py b/mcrouter/test/test_ascii_error.py
index a485c5ba2..8bfb28ed5 100644
--- a/mcrouter/test/test_ascii_error.py
+++ b/mcrouter/test/test_ascii_error.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.McrouterTestCase import McrouterTestCase
diff --git a/mcrouter/test/test_ascii_multiget_mock.py b/mcrouter/test/test_ascii_multiget_mock.py
index bdad6949a..6713f65f7 100644
--- a/mcrouter/test/test_ascii_multiget_mock.py
+++ b/mcrouter/test/test_ascii_multiget_mock.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import MockMemcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_async_files.py b/mcrouter/test/test_async_files.py
index 87ce18461..fcfc399bb 100644
--- a/mcrouter/test/test_async_files.py
+++ b/mcrouter/test/test_async_files.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import json
 import os
diff --git a/mcrouter/test/test_async_files_attr.py b/mcrouter/test/test_async_files_attr.py
index 962e9be26..208201c83 100644
--- a/mcrouter/test/test_async_files_attr.py
+++ b/mcrouter/test/test_async_files_attr.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import importlib.resources
 import json
diff --git a/mcrouter/test/test_axonlog.py b/mcrouter/test/test_axonlog.py
index 5bd93026b..feeaf5d03 100644
--- a/mcrouter/test/test_axonlog.py
+++ b/mcrouter/test/test_axonlog.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 from mcrouter.test.mock_servers import DeadServer
 
diff --git a/mcrouter/test/test_bad_params.py b/mcrouter/test/test_bad_params.py
index e6ce606ce..d4ac6beb7 100644
--- a/mcrouter/test/test_bad_params.py
+++ b/mcrouter/test/test_bad_params.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import re
 import signal
 import socket
diff --git a/mcrouter/test/test_bigvalue.py b/mcrouter/test/test_bigvalue.py
index 701913f56..b6e165bbc 100644
--- a/mcrouter/test/test_bigvalue.py
+++ b/mcrouter/test/test_bigvalue.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_bucketized_poolroute.py b/mcrouter/test/test_bucketized_poolroute.py
index 0b877779f..85967c8a9 100644
--- a/mcrouter/test/test_bucketized_poolroute.py
+++ b/mcrouter/test/test_bucketized_poolroute.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_carbonlookaside_route.py b/mcrouter/test/test_carbonlookaside_route.py
index c4b0666f6..aa1cb6eea 100644
--- a/mcrouter/test/test_carbonlookaside_route.py
+++ b/mcrouter/test/test_carbonlookaside_route.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import os
 import queue
 import tempfile
diff --git a/mcrouter/test/test_config_params.py b/mcrouter/test/test_config_params.py
index 9df81d9df..8f6599a2e 100644
--- a/mcrouter/test/test_config_params.py
+++ b/mcrouter/test/test_config_params.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import tempfile
 import time
 
diff --git a/mcrouter/test/test_const_shard_hash.py b/mcrouter/test/test_const_shard_hash.py
index f51cf4b2d..ad6f861e7 100644
--- a/mcrouter/test/test_const_shard_hash.py
+++ b/mcrouter/test/test_const_shard_hash.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_custom_failover.py b/mcrouter/test/test_custom_failover.py
index e24213bf3..741745189 100644
--- a/mcrouter/test/test_custom_failover.py
+++ b/mcrouter/test/test_custom_failover.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
diff --git a/mcrouter/test/test_debug_fifos.py b/mcrouter/test/test_debug_fifos.py
index bc310ef6a..4f57dcc1d 100644
--- a/mcrouter/test/test_debug_fifos.py
+++ b/mcrouter/test/test_debug_fifos.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import os
 import time
 
diff --git a/mcrouter/test/test_deterministic_failover.py b/mcrouter/test/test_deterministic_failover.py
index e9e816699..9b0a6f554 100644
--- a/mcrouter/test/test_deterministic_failover.py
+++ b/mcrouter/test/test_deterministic_failover.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Mcrouter
diff --git a/mcrouter/test/test_dump_config.py b/mcrouter/test/test_dump_config.py
index 9f0990cea..d5a5517cf 100644
--- a/mcrouter/test/test_dump_config.py
+++ b/mcrouter/test/test_dump_config.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import os
 import shutil
 import time
diff --git a/mcrouter/test/test_empty_pool.py b/mcrouter/test/test_empty_pool.py
index 36dc3c4d6..d04413a2e 100644
--- a/mcrouter/test/test_empty_pool.py
+++ b/mcrouter/test/test_empty_pool.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
 
diff --git a/mcrouter/test/test_flush_all.py b/mcrouter/test/test_flush_all.py
index 58f80cfa6..abc0412f3 100644
--- a/mcrouter/test/test_flush_all.py
+++ b/mcrouter/test/test_flush_all.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import MockMemcached
diff --git a/mcrouter/test/test_largeobj.py b/mcrouter/test/test_largeobj.py
index d054237c1..711e5258e 100644
--- a/mcrouter/test/test_largeobj.py
+++ b/mcrouter/test/test_largeobj.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 from mcrouter.test.mock_servers import StoreServer
 
diff --git a/mcrouter/test/test_latency_injection_route.py b/mcrouter/test/test_latency_injection_route.py
index c7f591938..f1eeedd66 100644
--- a/mcrouter/test/test_latency_injection_route.py
+++ b/mcrouter/test/test_latency_injection_route.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from datetime import datetime
 
 from mcrouter.test.MCProcess import Memcached
diff --git a/mcrouter/test/test_lease_pairing.py b/mcrouter/test/test_lease_pairing.py
index 3ce2bc321..04807ffa3 100644
--- a/mcrouter/test/test_lease_pairing.py
+++ b/mcrouter/test/test_lease_pairing.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 from mcrouter.test.MCProcess import McrouterClients, Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
diff --git a/mcrouter/test/test_linenumbers.py b/mcrouter/test/test_linenumbers.py
index 2156001e6..a832920b9 100644
--- a/mcrouter/test/test_linenumbers.py
+++ b/mcrouter/test/test_linenumbers.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import signal
 import subprocess
 import tempfile
diff --git a/mcrouter/test/test_loadbalancer_route.py b/mcrouter/test/test_loadbalancer_route.py
index cf2a0e593..3af0ca8f3 100644
--- a/mcrouter/test/test_loadbalancer_route.py
+++ b/mcrouter/test/test_loadbalancer_route.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Mcrouter, MockMemcachedDual
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_logging_route.py b/mcrouter/test/test_logging_route.py
index 97d1646d5..abe438748 100644
--- a/mcrouter/test/test_logging_route.py
+++ b/mcrouter/test/test_logging_route.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_logical_routing_policies.py b/mcrouter/test/test_logical_routing_policies.py
index 5e38d1435..1255aee37 100644
--- a/mcrouter/test/test_logical_routing_policies.py
+++ b/mcrouter/test/test_logical_routing_policies.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import *
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_max_shadow_requests.py b/mcrouter/test/test_max_shadow_requests.py
index 0ee351c02..145737c50 100644
--- a/mcrouter/test/test_max_shadow_requests.py
+++ b/mcrouter/test/test_max_shadow_requests.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Memcached
diff --git a/mcrouter/test/test_mcpiper.py b/mcrouter/test/test_mcpiper.py
index 04cae523c..13522d232 100644
--- a/mcrouter/test/test_mcpiper.py
+++ b/mcrouter/test/test_mcpiper.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import time
 
diff --git a/mcrouter/test/test_mcrefill.py b/mcrouter/test/test_mcrefill.py
index e94027443..ec6bb28eb 100644
--- a/mcrouter/test/test_mcrefill.py
+++ b/mcrouter/test/test_mcrefill.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_mcrouter.py b/mcrouter/test/test_mcrouter.py
index 3c24220c2..d17d7ae06 100644
--- a/mcrouter/test/test_mcrouter.py
+++ b/mcrouter/test/test_mcrouter.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import time
 
diff --git a/mcrouter/test/test_mcrouter_basic.py b/mcrouter/test/test_mcrouter_basic.py
index 16fde5f89..c92ae9b67 100644
--- a/mcrouter/test/test_mcrouter_basic.py
+++ b/mcrouter/test/test_mcrouter_basic.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import time
 from threading import Thread
diff --git a/mcrouter/test/test_mcrouter_errors.py b/mcrouter/test/test_mcrouter_errors.py
index 7f6bdb5d9..6a062ea23 100644
--- a/mcrouter/test/test_mcrouter_errors.py
+++ b/mcrouter/test/test_mcrouter_errors.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import errno
 import re
 import socket
diff --git a/mcrouter/test/test_mcrouter_processing_time.py b/mcrouter/test/test_mcrouter_processing_time.py
index e7d181a0a..7e7a77be7 100644
--- a/mcrouter/test/test_mcrouter_processing_time.py
+++ b/mcrouter/test/test_mcrouter_processing_time.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import json
 import os
 import tempfile
diff --git a/mcrouter/test/test_mcrouter_sanity_mock.py b/mcrouter/test/test_mcrouter_sanity_mock.py
index c0d81665e..a6d73287f 100644
--- a/mcrouter/test/test_mcrouter_sanity_mock.py
+++ b/mcrouter/test/test_mcrouter_sanity_mock.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import random
 
diff --git a/mcrouter/test/test_mcrouter_serialized.py b/mcrouter/test/test_mcrouter_serialized.py
index c59049705..09f2aab77 100644
--- a/mcrouter/test/test_mcrouter_serialized.py
+++ b/mcrouter/test/test_mcrouter_serialized.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import time
 
diff --git a/mcrouter/test/test_mcrouter_states.py b/mcrouter/test/test_mcrouter_states.py
index 437a38c1a..544bcdcce 100644
--- a/mcrouter/test/test_mcrouter_states.py
+++ b/mcrouter/test/test_mcrouter_states.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import McrouterClient, Memcached
diff --git a/mcrouter/test/test_mcrouter_to_mcrouter_tko.py b/mcrouter/test/test_mcrouter_to_mcrouter_tko.py
index 07a0cf45b..4511b8050 100644
--- a/mcrouter/test/test_mcrouter_to_mcrouter_tko.py
+++ b/mcrouter/test/test_mcrouter_to_mcrouter_tko.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import re
 import time
 
diff --git a/mcrouter/test/test_memcache_router.py b/mcrouter/test/test_memcache_router.py
index 2b3e83f87..3e3274dbc 100644
--- a/mcrouter/test/test_memcache_router.py
+++ b/mcrouter/test/test_memcache_router.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_migrated_failover.py b/mcrouter/test/test_migrated_failover.py
index 0e382eebe..342928de7 100644
--- a/mcrouter/test/test_migrated_failover.py
+++ b/mcrouter/test/test_migrated_failover.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_miss_on_error_arith_ops.py b/mcrouter/test/test_miss_on_error_arith_ops.py
index 86ea7918d..528ad9d51 100644
--- a/mcrouter/test/test_miss_on_error_arith_ops.py
+++ b/mcrouter/test/test_miss_on_error_arith_ops.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 from mcrouter.test.mock_servers import CustomErrorServer
 
diff --git a/mcrouter/test/test_modify_exptime.py b/mcrouter/test/test_modify_exptime.py
index 0c5f6118f..e16479b2e 100644
--- a/mcrouter/test/test_modify_exptime.py
+++ b/mcrouter/test/test_modify_exptime.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Memcached
diff --git a/mcrouter/test/test_modify_key.py b/mcrouter/test/test_modify_key.py
index 5e932bfde..76854a385 100644
--- a/mcrouter/test/test_modify_key.py
+++ b/mcrouter/test/test_modify_key.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Memcached
diff --git a/mcrouter/test/test_named_handles.py b/mcrouter/test/test_named_handles.py
index a5b2d1bbd..132b919da 100644
--- a/mcrouter/test/test_named_handles.py
+++ b/mcrouter/test/test_named_handles.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_noreply.py b/mcrouter/test/test_noreply.py
index 91030c830..36c78ea27 100644
--- a/mcrouter/test/test_noreply.py
+++ b/mcrouter/test/test_noreply.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_operation_selector_route.py b/mcrouter/test/test_operation_selector_route.py
index 7e4b88791..f3cfc9396 100644
--- a/mcrouter/test/test_operation_selector_route.py
+++ b/mcrouter/test/test_operation_selector_route.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_poolstats.py b/mcrouter/test/test_poolstats.py
index 794d41631..6b089f6a4 100644
--- a/mcrouter/test/test_poolstats.py
+++ b/mcrouter/test/test_poolstats.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import os
 
 import time
diff --git a/mcrouter/test/test_probe_timeout.py b/mcrouter/test/test_probe_timeout.py
index c9b48a5c3..507c0c9ce 100644
--- a/mcrouter/test/test_probe_timeout.py
+++ b/mcrouter/test/test_probe_timeout.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import shutil
 import time
 
diff --git a/mcrouter/test/test_rendezvous_failover.py b/mcrouter/test/test_rendezvous_failover.py
index beb83219e..b19ad8fd4 100644
--- a/mcrouter/test/test_rendezvous_failover.py
+++ b/mcrouter/test/test_rendezvous_failover.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Mcrouter
diff --git a/mcrouter/test/test_routing_group_route.py b/mcrouter/test/test_routing_group_route.py
index 0d5017413..f747b928b 100644
--- a/mcrouter/test/test_routing_group_route.py
+++ b/mcrouter/test/test_routing_group_route.py
@@ -3,6 +3,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
diff --git a/mcrouter/test/test_routing_prefixes.py b/mcrouter/test/test_routing_prefixes.py
index 419022f37..914f7e518 100644
--- a/mcrouter/test/test_routing_prefixes.py
+++ b/mcrouter/test/test_routing_prefixes.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import time
 
diff --git a/mcrouter/test/test_send_to_all_hosts.py b/mcrouter/test/test_send_to_all_hosts.py
index ffcd11341..26c5c5e04 100644
--- a/mcrouter/test/test_send_to_all_hosts.py
+++ b/mcrouter/test/test_send_to_all_hosts.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_service_info.py b/mcrouter/test/test_service_info.py
index d0f8a4848..82916dbe7 100644
--- a/mcrouter/test/test_service_info.py
+++ b/mcrouter/test/test_service_info.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_shadow.py b/mcrouter/test/test_shadow.py
index cccf64a9e..d69531add 100644
--- a/mcrouter/test/test_shadow.py
+++ b/mcrouter/test/test_shadow.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Memcached
diff --git a/mcrouter/test/test_shadow_route.py b/mcrouter/test/test_shadow_route.py
index 888135b0f..901af6a06 100644
--- a/mcrouter/test/test_shadow_route.py
+++ b/mcrouter/test/test_shadow_route.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import time
 
diff --git a/mcrouter/test/test_shadow_with_file.py b/mcrouter/test/test_shadow_with_file.py
index 5489b88b3..0b1c16514 100644
--- a/mcrouter/test/test_shadow_with_file.py
+++ b/mcrouter/test/test_shadow_with_file.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from time import sleep
 
 from mcrouter.test.MCProcess import Mcrouter, Memcached
diff --git a/mcrouter/test/test_shard_splits.py b/mcrouter/test/test_shard_splits.py
index b546a1e64..70d04e754 100644
--- a/mcrouter/test/test_shard_splits.py
+++ b/mcrouter/test/test_shard_splits.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Memcached
diff --git a/mcrouter/test/test_slow_warmup.py b/mcrouter/test/test_slow_warmup.py
index cd7335905..6f2bab0f8 100644
--- a/mcrouter/test/test_slow_warmup.py
+++ b/mcrouter/test/test_slow_warmup.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 from mcrouter.test.MCProcess import Memcached
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 
diff --git a/mcrouter/test/test_stats.py b/mcrouter/test/test_stats.py
index 4a7a7be33..4ef350781 100644
--- a/mcrouter/test/test_stats.py
+++ b/mcrouter/test/test_stats.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 from mcrouter.test.McrouterTestCase import McrouterTestCase
 from mcrouter.test.mock_servers import CustomErrorServer, SleepServer
diff --git a/mcrouter/test/test_tko_inactive.py b/mcrouter/test/test_tko_inactive.py
index 4b2d5190b..a6f0713e4 100644
--- a/mcrouter/test/test_tko_inactive.py
+++ b/mcrouter/test/test_tko_inactive.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.McrouterTestCase import McrouterTestCase
diff --git a/mcrouter/test/test_tko_reconfigure.py b/mcrouter/test/test_tko_reconfigure.py
index 1e0d6368a..d55296c11 100644
--- a/mcrouter/test/test_tko_reconfigure.py
+++ b/mcrouter/test/test_tko_reconfigure.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import shutil
 import tempfile
 import time
diff --git a/mcrouter/test/test_validate_config.py b/mcrouter/test/test_validate_config.py
index e75be1145..29266489b 100644
--- a/mcrouter/test/test_validate_config.py
+++ b/mcrouter/test/test_validate_config.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import socket
 import time
 import unittest
diff --git a/mcrouter/test/test_warmup.py b/mcrouter/test/test_warmup.py
index b0acbc732..cf3967f1d 100644
--- a/mcrouter/test/test_warmup.py
+++ b/mcrouter/test/test_warmup.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 import time
 
 from mcrouter.test.MCProcess import Memcached
diff --git a/mcrouter/test/test_warmup2.py b/mcrouter/test/test_warmup2.py
index 9c9b992d5..ee65295ee 100644
--- a/mcrouter/test/test_warmup2.py
+++ b/mcrouter/test/test_warmup2.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 import time
 
diff --git a/mcrouter/test/test_wch3.py b/mcrouter/test/test_wch3.py
index 2e61ffbd7..507677946 100644
--- a/mcrouter/test/test_wch3.py
+++ b/mcrouter/test/test_wch3.py
@@ -4,6 +4,8 @@
 # This source code is licensed under the MIT license found in the
 # LICENSE file in the root directory of this source tree.
 
+# pyre-unsafe
+
 
 from collections import defaultdict