diff --git a/quic/api/test/QuicTransportFunctionsTest.cpp b/quic/api/test/QuicTransportFunctionsTest.cpp
index 07e889636..fae3beb59 100644
--- a/quic/api/test/QuicTransportFunctionsTest.cpp
+++ b/quic/api/test/QuicTransportFunctionsTest.cpp
@@ -20,7 +20,6 @@
 #include <gtest/gtest.h>
 
 using namespace folly;
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/client/handshake/test/ClientHandshakeTest.cpp b/quic/client/handshake/test/ClientHandshakeTest.cpp
index 15450629a..f72cc5af3 100644
--- a/quic/client/handshake/test/ClientHandshakeTest.cpp
+++ b/quic/client/handshake/test/ClientHandshakeTest.cpp
@@ -32,10 +32,7 @@
 #include <quic/state/StateData.h>
 
 using namespace std;
-using namespace quic;
 using namespace folly;
-using namespace folly::test;
-using namespace folly::ssl;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/client/test/QuicClientTransportTest.cpp b/quic/client/test/QuicClientTransportTest.cpp
index a157328e6..41ba2c8c7 100644
--- a/quic/client/test/QuicClientTransportTest.cpp
+++ b/quic/client/test/QuicClientTransportTest.cpp
@@ -33,9 +33,7 @@
 
 using namespace testing;
 using namespace folly;
-using namespace folly::io;
 using namespace quic::samples;
-using namespace quic::test;
 
 namespace quic {
 namespace test {
diff --git a/quic/codec/QuicWriteCodec.cpp b/quic/codec/QuicWriteCodec.cpp
index fa1222d21..aab2cfb96 100644
--- a/quic/codec/QuicWriteCodec.cpp
+++ b/quic/codec/QuicWriteCodec.cpp
@@ -9,7 +9,6 @@
 #include <quic/codec/QuicWriteCodec.h>
 
 #include <algorithm>
-#include <limits>
 
 #include <quic/QuicConstants.h>
 #include <quic/QuicException.h>
diff --git a/quic/codec/test/DecodeTest.cpp b/quic/codec/test/DecodeTest.cpp
index 54e3424ab..5bb30fcbd 100644
--- a/quic/codec/test/DecodeTest.cpp
+++ b/quic/codec/test/DecodeTest.cpp
@@ -15,7 +15,6 @@
 #include <quic/codec/Types.h>
 #include <quic/common/test/TestUtils.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/codec/test/PacketNumberTest.cpp b/quic/codec/test/PacketNumberTest.cpp
index a57003276..42e5b4a4a 100644
--- a/quic/codec/test/PacketNumberTest.cpp
+++ b/quic/codec/test/PacketNumberTest.cpp
@@ -10,9 +10,7 @@
 #include <folly/portability/GTest.h>
 #include <quic/codec/Types.h>
 
-using namespace quic;
 using namespace testing;
-using namespace folly;
 
 namespace quic {
 namespace test {
diff --git a/quic/codec/test/QuicConnectionIdTest.cpp b/quic/codec/test/QuicConnectionIdTest.cpp
index 33fff0640..7856176c5 100644
--- a/quic/codec/test/QuicConnectionIdTest.cpp
+++ b/quic/codec/test/QuicConnectionIdTest.cpp
@@ -13,7 +13,6 @@
 #include <folly/portability/GTest.h>
 
 using namespace testing;
-using namespace folly;
 
 namespace quic {
 namespace test {
diff --git a/quic/codec/test/QuicHeaderCodecTest.cpp b/quic/codec/test/QuicHeaderCodecTest.cpp
index 7238ff1c2..ae6feafac 100644
--- a/quic/codec/test/QuicHeaderCodecTest.cpp
+++ b/quic/codec/test/QuicHeaderCodecTest.cpp
@@ -14,8 +14,6 @@
 #include <quic/codec/QuicHeaderCodec.h>
 #include <quic/common/test/TestUtils.h>
 
-using namespace quic;
-using namespace quic::test;
 using namespace testing;
 using namespace folly;
 
diff --git a/quic/codec/test/QuicIntegerTest.cpp b/quic/codec/test/QuicIntegerTest.cpp
index d3368ec67..2a0e79490 100644
--- a/quic/codec/test/QuicIntegerTest.cpp
+++ b/quic/codec/test/QuicIntegerTest.cpp
@@ -15,7 +15,6 @@
 #include <quic/QuicException.h>
 #include <quic/codec/QuicInteger.h>
 
-using namespace quic;
 using namespace testing;
 using namespace folly;
 
diff --git a/quic/codec/test/QuicPacketRebuilderTest.cpp b/quic/codec/test/QuicPacketRebuilderTest.cpp
index 4c1b1e0f4..a608829f9 100644
--- a/quic/codec/test/QuicPacketRebuilderTest.cpp
+++ b/quic/codec/test/QuicPacketRebuilderTest.cpp
@@ -17,7 +17,6 @@
 #include <quic/state/StateData.h>
 #include <quic/state/stream/StreamStateFunctions.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/codec/test/QuicWriteCodecTest.cpp b/quic/codec/test/QuicWriteCodecTest.cpp
index db1eed552..08124f8d3 100644
--- a/quic/codec/test/QuicWriteCodecTest.cpp
+++ b/quic/codec/test/QuicWriteCodecTest.cpp
@@ -21,7 +21,6 @@
 using namespace quic;
 using namespace quic::test;
 using namespace testing;
-using namespace std::chrono;
 
 ShortHeader buildTestShortHeader() {
   return ShortHeader(ProtectionType::KeyPhaseZero, getTestConnectionId(), 0x01);
diff --git a/quic/codec/test/TypesTest.cpp b/quic/codec/test/TypesTest.cpp
index ad7eebc87..ed01a4fde 100644
--- a/quic/codec/test/TypesTest.cpp
+++ b/quic/codec/test/TypesTest.cpp
@@ -17,7 +17,6 @@
 #include <quic/codec/DefaultConnectionIdAlgo.h>
 #include <quic/common/test/TestUtils.h>
 
-using namespace quic;
 using namespace testing;
 using namespace folly;
 
diff --git a/quic/common/test/FunctionLooperTest.cpp b/quic/common/test/FunctionLooperTest.cpp
index ce7b904a1..997e0d3c6 100644
--- a/quic/common/test/FunctionLooperTest.cpp
+++ b/quic/common/test/FunctionLooperTest.cpp
@@ -11,7 +11,6 @@
 
 using namespace std;
 using namespace folly;
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/common/test/IntervalSetTest.cpp b/quic/common/test/IntervalSetTest.cpp
index 2e94a34ad..3489d11f0 100644
--- a/quic/common/test/IntervalSetTest.cpp
+++ b/quic/common/test/IntervalSetTest.cpp
@@ -11,7 +11,6 @@
 
 using namespace std;
 using namespace quic;
-using namespace testing;
 
 TEST(IntervalSet, empty) {
   IntervalSet<int> set;
diff --git a/quic/common/test/QuicCodecUtilsTest.cpp b/quic/common/test/QuicCodecUtilsTest.cpp
index a85274351..682d0cfe3 100644
--- a/quic/common/test/QuicCodecUtilsTest.cpp
+++ b/quic/common/test/QuicCodecUtilsTest.cpp
@@ -13,7 +13,6 @@
 #include <iterator>
 
 using namespace testing;
-using namespace folly;
 
 namespace quic {
 namespace test {
diff --git a/quic/common/test/TimeUtilTest.cpp b/quic/common/test/TimeUtilTest.cpp
index 79efb3224..546ca3ee4 100644
--- a/quic/common/test/TimeUtilTest.cpp
+++ b/quic/common/test/TimeUtilTest.cpp
@@ -12,9 +12,7 @@
 namespace quic {
 namespace test {
 
-using namespace std;
 using namespace quic;
-using namespace testing;
 
 TEST(TimeUtil, TestMinTwo) {
   std::chrono::milliseconds ms1 = 10ms;
diff --git a/quic/congestion_control/test/BandwidthTest.cpp b/quic/congestion_control/test/BandwidthTest.cpp
index 65626b94e..4ccc78ada 100644
--- a/quic/congestion_control/test/BandwidthTest.cpp
+++ b/quic/congestion_control/test/BandwidthTest.cpp
@@ -11,7 +11,6 @@
 #include <folly/portability/GTest.h>
 #include <quic/congestion_control/Bbr.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/congestion_control/test/BbrBandwidthSamplerTest.cpp b/quic/congestion_control/test/BbrBandwidthSamplerTest.cpp
index c9a5f85b4..ee0411965 100644
--- a/quic/congestion_control/test/BbrBandwidthSamplerTest.cpp
+++ b/quic/congestion_control/test/BbrBandwidthSamplerTest.cpp
@@ -13,7 +13,6 @@
 #include <folly/portability/GTest.h>
 #include <quic/common/test/TestUtils.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/congestion_control/test/BbrRttSamplerTest.cpp b/quic/congestion_control/test/BbrRttSamplerTest.cpp
index a10f228ae..61f70bff7 100644
--- a/quic/congestion_control/test/BbrRttSamplerTest.cpp
+++ b/quic/congestion_control/test/BbrRttSamplerTest.cpp
@@ -12,7 +12,6 @@
 #include <folly/portability/GMock.h>
 #include <folly/portability/GTest.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/congestion_control/test/BbrTest.cpp b/quic/congestion_control/test/BbrTest.cpp
index 615f7f2f5..2ead97e8d 100644
--- a/quic/congestion_control/test/BbrTest.cpp
+++ b/quic/congestion_control/test/BbrTest.cpp
@@ -14,7 +14,6 @@
 #include <quic/common/test/TestUtils.h>
 #include <quic/congestion_control/BbrBandwidthSampler.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/congestion_control/test/CongestionControlFunctionsTest.cpp b/quic/congestion_control/test/CongestionControlFunctionsTest.cpp
index 0407ac4fb..f8654ab8f 100644
--- a/quic/congestion_control/test/CongestionControlFunctionsTest.cpp
+++ b/quic/congestion_control/test/CongestionControlFunctionsTest.cpp
@@ -12,7 +12,6 @@
 #include <quic/QuicConstants.h>
 #include <quic/state/StateData.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/congestion_control/test/CopaTest.cpp b/quic/congestion_control/test/CopaTest.cpp
index dfdec7ec4..ce82afa0c 100644
--- a/quic/congestion_control/test/CopaTest.cpp
+++ b/quic/congestion_control/test/CopaTest.cpp
@@ -12,7 +12,6 @@
 #include <quic/common/test/TestUtils.h>
 
 using namespace testing;
-using namespace std::chrono_literals;
 
 namespace quic {
 namespace test {
diff --git a/quic/congestion_control/test/CubicHystartTest.cpp b/quic/congestion_control/test/CubicHystartTest.cpp
index 4c7d2e0f5..bad2b9d45 100644
--- a/quic/congestion_control/test/CubicHystartTest.cpp
+++ b/quic/congestion_control/test/CubicHystartTest.cpp
@@ -10,8 +10,6 @@
 #include <quic/common/test/TestUtils.h>
 #include <quic/congestion_control/QuicCubic.h>
 
-using namespace quic;
-using namespace quic::test;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/congestion_control/test/CubicRecoveryTest.cpp b/quic/congestion_control/test/CubicRecoveryTest.cpp
index 5618fae65..ce99f7feb 100644
--- a/quic/congestion_control/test/CubicRecoveryTest.cpp
+++ b/quic/congestion_control/test/CubicRecoveryTest.cpp
@@ -10,8 +10,6 @@
 #include <quic/common/test/TestUtils.h>
 #include <quic/congestion_control/QuicCubic.h>
 
-using namespace quic;
-using namespace quic::test;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/congestion_control/test/CubicStateTest.cpp b/quic/congestion_control/test/CubicStateTest.cpp
index 09c9f599f..ba23ce77a 100644
--- a/quic/congestion_control/test/CubicStateTest.cpp
+++ b/quic/congestion_control/test/CubicStateTest.cpp
@@ -10,8 +10,6 @@
 #include <quic/common/test/TestUtils.h>
 #include <quic/congestion_control/test/TestingCubic.h>
 
-using namespace quic;
-using namespace quic::test;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/congestion_control/test/CubicTest.cpp b/quic/congestion_control/test/CubicTest.cpp
index d9576ac31..caf94f827 100644
--- a/quic/congestion_control/test/CubicTest.cpp
+++ b/quic/congestion_control/test/CubicTest.cpp
@@ -10,8 +10,6 @@
 #include <quic/common/test/TestUtils.h>
 #include <quic/congestion_control/test/TestingCubic.h>
 
-using namespace quic;
-using namespace quic::test;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/handshake/test/FizzCryptoFactoryTest.cpp b/quic/handshake/test/FizzCryptoFactoryTest.cpp
index 8b759eaff..2dca5e3d4 100644
--- a/quic/handshake/test/FizzCryptoFactoryTest.cpp
+++ b/quic/handshake/test/FizzCryptoFactoryTest.cpp
@@ -15,7 +15,6 @@
 #include <quic/handshake/QuicFizzFactory.h>
 #include <quic/handshake/test/Mocks.h>
 
-using namespace folly;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/logging/test/QLoggerTest.cpp b/quic/logging/test/QLoggerTest.cpp
index a2718e45f..9224e1535 100644
--- a/quic/logging/test/QLoggerTest.cpp
+++ b/quic/logging/test/QLoggerTest.cpp
@@ -14,7 +14,6 @@
 #include <quic/congestion_control/Bbr.h>
 #include <quic/logging/FileQLogger.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic::test {
diff --git a/quic/logging/test/QuicLoggingMacroTest.cpp b/quic/logging/test/QuicLoggingMacroTest.cpp
index 3bc1b1590..afceedf27 100644
--- a/quic/logging/test/QuicLoggingMacroTest.cpp
+++ b/quic/logging/test/QuicLoggingMacroTest.cpp
@@ -9,7 +9,6 @@
 #include <folly/portability/GTest.h>
 #include <quic/logging/QuicLogger.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/loss/test/QuicLossFunctionsTest.cpp b/quic/loss/test/QuicLossFunctionsTest.cpp
index a92147297..02e44d6c7 100644
--- a/quic/loss/test/QuicLossFunctionsTest.cpp
+++ b/quic/loss/test/QuicLossFunctionsTest.cpp
@@ -23,7 +23,6 @@
 using namespace folly::test;
 using namespace testing;
 using namespace folly;
-using namespace std::chrono_literals;
 
 namespace quic {
 namespace test {
diff --git a/quic/server/handshake/DefaultAppTokenValidator.cpp b/quic/server/handshake/DefaultAppTokenValidator.cpp
index 9c3e77bbb..c9b08b0e6 100644
--- a/quic/server/handshake/DefaultAppTokenValidator.cpp
+++ b/quic/server/handshake/DefaultAppTokenValidator.cpp
@@ -22,7 +22,6 @@
 #include <glog/logging.h>
 
 #include <chrono>
-#include <cstdint>
 #include <string>
 #include <vector>
 
diff --git a/quic/server/handshake/ServerHandshake.cpp b/quic/server/handshake/ServerHandshake.cpp
index 26426ee42..742acb9c1 100644
--- a/quic/server/handshake/ServerHandshake.cpp
+++ b/quic/server/handshake/ServerHandshake.cpp
@@ -14,7 +14,6 @@
 #include <quic/state/QuicStreamFunctions.h>
 
 namespace quic {
-using namespace std::chrono_literals;
 ServerHandshake::ServerHandshake(QuicCryptoState& cryptoState)
     : cryptoState_(cryptoState), visitor_(*this) {}
 
diff --git a/quic/server/handshake/test/AppTokenTest.cpp b/quic/server/handshake/test/AppTokenTest.cpp
index b5dd707ba..5006632da 100644
--- a/quic/server/handshake/test/AppTokenTest.cpp
+++ b/quic/server/handshake/test/AppTokenTest.cpp
@@ -18,9 +18,6 @@
 
 #include <cstdint>
 
-using namespace fizz;
-using namespace fizz::server;
-using namespace quic;
 
 namespace quic {
 namespace test {
diff --git a/quic/server/handshake/test/DefaultAppTokenValidatorTest.cpp b/quic/server/handshake/test/DefaultAppTokenValidatorTest.cpp
index e9254a4f7..b76ffab22 100644
--- a/quic/server/handshake/test/DefaultAppTokenValidatorTest.cpp
+++ b/quic/server/handshake/test/DefaultAppTokenValidatorTest.cpp
@@ -18,11 +18,8 @@
 #include <gmock/gmock.h>
 #include <gtest/gtest.h>
 
-#include <cstdint>
 
-using namespace fizz;
 using namespace fizz::server;
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/server/handshake/test/ServerHandshakeTest.cpp b/quic/server/handshake/test/ServerHandshakeTest.cpp
index fa65ff923..702559875 100644
--- a/quic/server/handshake/test/ServerHandshakeTest.cpp
+++ b/quic/server/handshake/test/ServerHandshakeTest.cpp
@@ -34,10 +34,7 @@
 #include <quic/state/StateData.h>
 
 using namespace std;
-using namespace quic;
 using namespace folly;
-using namespace folly::test;
-using namespace folly::ssl;
 using namespace testing;
 
 static constexpr StringPiece kTestHostname = "www.facebook.com";
diff --git a/quic/server/handshake/test/ServerTransportParametersTest.cpp b/quic/server/handshake/test/ServerTransportParametersTest.cpp
index 51566e394..5822ef0da 100644
--- a/quic/server/handshake/test/ServerTransportParametersTest.cpp
+++ b/quic/server/handshake/test/ServerTransportParametersTest.cpp
@@ -17,7 +17,6 @@
 
 using namespace fizz;
 using namespace fizz::test;
-using namespace quic;
 
 namespace quic {
 namespace test {
diff --git a/quic/server/handshake/test/StatelessResetGeneratorTest.cpp b/quic/server/handshake/test/StatelessResetGeneratorTest.cpp
index b35949eaf..c18aa8e93 100644
--- a/quic/server/handshake/test/StatelessResetGeneratorTest.cpp
+++ b/quic/server/handshake/test/StatelessResetGeneratorTest.cpp
@@ -11,7 +11,6 @@
 #include <folly/SocketAddress.h>
 #include <folly/portability/GTest.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/server/test/QuicServerTest.cpp b/quic/server/test/QuicServerTest.cpp
index 85f119916..8502b960a 100644
--- a/quic/server/test/QuicServerTest.cpp
+++ b/quic/server/test/QuicServerTest.cpp
@@ -23,7 +23,6 @@
 
 using namespace testing;
 using namespace folly;
-using namespace folly::io;
 
 const folly::SocketAddress kClientAddr("1.2.3.4", 1234);
 
diff --git a/quic/state/test/AckHandlersTest.cpp b/quic/state/test/AckHandlersTest.cpp
index ddd7c6d2b..4ea012496 100644
--- a/quic/state/test/AckHandlersTest.cpp
+++ b/quic/state/test/AckHandlersTest.cpp
@@ -20,7 +20,6 @@
 
 using namespace folly;
 using namespace testing;
-using namespace std::chrono_literals;
 
 namespace quic {
 namespace test {
diff --git a/quic/state/test/QuicPacingFunctionsTest.cpp b/quic/state/test/QuicPacingFunctionsTest.cpp
index 155be07df..7dc610a80 100644
--- a/quic/state/test/QuicPacingFunctionsTest.cpp
+++ b/quic/state/test/QuicPacingFunctionsTest.cpp
@@ -10,7 +10,6 @@
 
 #include <folly/portability/GTest.h>
 
-using namespace quic;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/state/test/QuicStateFunctionsTest.cpp b/quic/state/test/QuicStateFunctionsTest.cpp
index 684f9daee..f610dcfbc 100644
--- a/quic/state/test/QuicStateFunctionsTest.cpp
+++ b/quic/state/test/QuicStateFunctionsTest.cpp
@@ -14,7 +14,6 @@
 #include <quic/state/QuicStateFunctions.h>
 #include <quic/state/test/Mocks.h>
 
-using namespace folly;
 using namespace testing;
 
 namespace quic {
diff --git a/quic/state/test/QuicStreamManagerTest.cpp b/quic/state/test/QuicStreamManagerTest.cpp
index f6732d248..71920b560 100644
--- a/quic/state/test/QuicStreamManagerTest.cpp
+++ b/quic/state/test/QuicStreamManagerTest.cpp
@@ -13,7 +13,6 @@
 #include <quic/state/QuicStreamManager.h>
 #include <quic/state/test/Mocks.h>
 
-using namespace folly;
 using namespace testing;
 
 namespace quic {