diff --git a/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp b/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp
index 3d22aac..dc5732f 100644
--- a/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp
+++ b/service-t/native/libs/libnetworkstats/NetworkTraceHandler.cpp
@@ -136,10 +136,12 @@
 }
 
 void NetworkTraceHandler::OnStart(const StartArgs&) {
+  if (mIsTest) return;  // Don't touch non-hermetic bpf in test.
   mStarted = sPoller.Start(mPollMs);
 }
 
 void NetworkTraceHandler::OnStop(const StopArgs&) {
+  if (mIsTest) return;  // Don't touch non-hermetic bpf in test.
   if (mStarted) sPoller.Stop();
   mStarted = false;
 }
diff --git a/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp b/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp
index 27dce75..f2c1a86 100644
--- a/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp
+++ b/service-t/native/libs/libnetworkstats/NetworkTraceHandlerTest.cpp
@@ -33,14 +33,6 @@
 using ::perfetto::protos::TracePacket;
 using ::perfetto::protos::TrafficDirection;
 
-// This handler makes OnStart and OnStop a no-op so that tracing is not really
-// started on the device.
-class HandlerForTest : public NetworkTraceHandler {
- public:
-  void OnStart(const StartArgs&) override {}
-  void OnStop(const StopArgs&) override {}
-};
-
 class NetworkTraceHandlerTest : public testing::Test {
  protected:
   // Starts a tracing session with the handler under test.
@@ -52,7 +44,7 @@
 
     perfetto::DataSourceDescriptor dsd;
     dsd.set_name("test.network_packets");
-    HandlerForTest::Register(dsd);
+    NetworkTraceHandler::Register(dsd, /*isTest=*/true);
 
     perfetto::TraceConfig cfg;
     cfg.add_buffers()->set_size_kb(1024);
@@ -94,7 +86,7 @@
                            std::vector<TracePacket>* output,
                            NetworkPacketTraceConfig config = {}) {
     auto session = StartTracing(config);
-    HandlerForTest::Trace([&](HandlerForTest::TraceContext ctx) {
+    NetworkTraceHandler::Trace([&](NetworkTraceHandler::TraceContext ctx) {
       ctx.GetDataSourceLocked()->Write(input, ctx);
       ctx.Flush();
     });
@@ -357,7 +349,7 @@
 
   auto session = StartTracing(config);
 
-  HandlerForTest::Trace([&](HandlerForTest::TraceContext ctx) {
+  NetworkTraceHandler::Trace([&](NetworkTraceHandler::TraceContext ctx) {
     ctx.GetDataSourceLocked()->Write(inputs[0], ctx);
     ctx.GetDataSourceLocked()->Write(inputs[1], ctx);
     ctx.GetDataSourceLocked()->Write(inputs[2], ctx);
diff --git a/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h b/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h
index 9bc777b..bc10e68 100644
--- a/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h
+++ b/service-t/native/libs/libnetworkstats/include/netdbpf/NetworkTraceHandler.h
@@ -70,6 +70,9 @@
   // Connects to the system Perfetto daemon and registers the trace handler.
   static void InitPerfettoTracing();
 
+  // When isTest is true, skip non-hermetic code.
+  NetworkTraceHandler(bool isTest = false) : mIsTest(isTest) {}
+
   // perfetto::DataSource overrides:
   void OnSetup(const SetupArgs& args) override;
   void OnStart(const StartArgs&) override;
@@ -92,6 +95,7 @@
 
   static internal::NetworkTracePoller sPoller;
   bool mStarted;
+  bool mIsTest;
 
   // Values from config, see proto for details.
   uint32_t mPollMs;