diff --git a/tests/unit/Android.bp b/tests/unit/Android.bp
index 7b23255..4720706 100644
--- a/tests/unit/Android.bp
+++ b/tests/unit/Android.bp
@@ -66,6 +66,7 @@
         "framework-protos",
         "mockito-target-minus-junit4",
         "net-tests-utils",
+        "platform-compat-test-rules",
         "platform-test-annotations",
         "service-connectivity-pre-jarjar",
         "services.core",
diff --git a/tests/unit/java/android/net/nsd/NsdManagerTest.java b/tests/unit/java/android/net/nsd/NsdManagerTest.java
index 31c8927..de77d23 100644
--- a/tests/unit/java/android/net/nsd/NsdManagerTest.java
+++ b/tests/unit/java/android/net/nsd/NsdManagerTest.java
@@ -16,6 +16,9 @@
 
 package android.net.nsd;
 
+import static libcore.junit.util.compat.CoreCompatChangeRule.DisableCompatChanges;
+import static libcore.junit.util.compat.CoreCompatChangeRule.EnableCompatChanges;
+
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.fail;
@@ -27,6 +30,7 @@
 import static org.mockito.Mockito.timeout;
 import static org.mockito.Mockito.verify;
 
+import android.compat.testing.PlatformCompatChangeRule;
 import android.content.Context;
 import android.os.Build;
 import android.os.Handler;
@@ -44,7 +48,9 @@
 
 import org.junit.After;
 import org.junit.Before;
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.TestRule;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
@@ -56,6 +62,9 @@
 
     static final int PROTOCOL = NsdManager.PROTOCOL_DNS_SD;
 
+    @Rule
+    public TestRule compatChangeRule = new PlatformCompatChangeRule();
+
     @Mock Context mContext;
     @Mock INsdManager mService;
     MockServiceHandler mServiceHandler;
@@ -70,8 +79,6 @@
 
         mServiceHandler = spy(MockServiceHandler.create(mContext));
         doReturn(new Messenger(mServiceHandler)).when(mService).getMessenger();
-
-        mManager = makeManager();
     }
 
     @After
@@ -85,7 +92,76 @@
     }
 
     @Test
-    public void testResolveService() {
+    @EnableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testResolveServiceS() {
+        mManager = makeNsdManagerS();
+        doTestResolveService();
+    }
+
+    @Test
+    @DisableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testResolveServicePreS() {
+        mManager = makeNsdManagerPreS();
+        doTestResolveService();
+    }
+
+    @Test
+    @EnableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testDiscoverServiceS() {
+        mManager = makeNsdManagerS();
+        doTestDiscoverService();
+    }
+
+    @Test
+    @DisableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testDiscoverServicePreS() {
+        mManager = makeNsdManagerPreS();
+        doTestDiscoverService();
+    }
+
+    @Test
+    @EnableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testParallelResolveServiceS() {
+        mManager = makeNsdManagerS();
+        doTestParallelResolveService();
+    }
+
+    @Test
+    @DisableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testParallelResolveServicePreS() {
+        mManager = makeNsdManagerPreS();
+        doTestParallelResolveService();
+    }
+
+    @Test
+    @EnableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testInvalidCallsS() {
+        mManager = makeNsdManagerS();
+        doTestInvalidCalls();
+    }
+
+    @Test
+    @DisableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testInvalidCallsPreS() {
+        mManager = makeNsdManagerPreS();
+        doTestInvalidCalls();
+    }
+
+    @Test
+    @EnableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testRegisterServiceS() {
+        mManager = makeNsdManagerS();
+        doTestRegisterService();
+    }
+
+    @Test
+    @DisableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testRegisterServicePreS() {
+        mManager = makeNsdManagerPreS();
+        doTestRegisterService();
+    }
+
+    public void doTestResolveService() {
         NsdManager manager = mManager;
 
         NsdServiceInfo request = new NsdServiceInfo("a_name", "a_type");
@@ -104,8 +180,7 @@
         verify(listener, timeout(mTimeoutMs).times(1)).onServiceResolved(reply);
     }
 
-    @Test
-    public void testParallelResolveService() {
+    public void doTestParallelResolveService() {
         NsdManager manager = mManager;
 
         NsdServiceInfo request = new NsdServiceInfo("a_name", "a_type");
@@ -127,8 +202,7 @@
         verify(listener2, timeout(mTimeoutMs).times(1)).onServiceResolved(reply);
     }
 
-    @Test
-    public void testRegisterService() {
+    public void doTestRegisterService() {
         NsdManager manager = mManager;
 
         NsdServiceInfo request1 = new NsdServiceInfo("a_name", "a_type");
@@ -186,8 +260,7 @@
         //verify(listener2, timeout(mTimeoutMs).times(1)).onServiceUnregistered(request2);
     }
 
-    @Test
-    public void testDiscoverService() {
+    public void doTestDiscoverService() {
         NsdManager manager = mManager;
 
         NsdServiceInfo reply1 = new NsdServiceInfo("a_name", "a_type");
@@ -264,8 +337,7 @@
         verify(listener, timeout(mTimeoutMs).times(0)).onServiceFound(reply1);
     }
 
-    @Test
-    public void testInvalidCalls() {
+    public void doTestInvalidCalls() {
         NsdManager manager = mManager;
 
         NsdManager.RegistrationListener listener1 = mock(NsdManager.RegistrationListener.class);
@@ -326,10 +398,21 @@
         }
     }
 
-    NsdManager makeManager() {
+    NsdManager makeNsdManagerS() {
+        // Expect we'll get 2 AsyncChannel related msgs.
+        return makeManager(2);
+    }
+
+    NsdManager makeNsdManagerPreS() {
+        // Expect we'll get 3 msgs. 2 AsyncChannel related msgs + 1 additional daemon startup msg.
+        return makeManager(3);
+    }
+
+    NsdManager makeManager(int expectedMsgCount) {
         NsdManager manager = new NsdManager(mContext, mService);
         // Acknowledge first two messages connecting the AsyncChannel.
-        verify(mServiceHandler, timeout(mTimeoutMs).times(2)).handleMessage(any());
+        verify(mServiceHandler, timeout(mTimeoutMs).times(expectedMsgCount)).handleMessage(any());
+
         reset(mServiceHandler);
         assertNotNull(mServiceHandler.chan);
         return manager;
diff --git a/tests/unit/java/com/android/server/NsdServiceTest.java b/tests/unit/java/com/android/server/NsdServiceTest.java
index e80a938..4d2970a 100644
--- a/tests/unit/java/com/android/server/NsdServiceTest.java
+++ b/tests/unit/java/com/android/server/NsdServiceTest.java
@@ -16,6 +16,9 @@
 
 package com.android.server;
 
+import static libcore.junit.util.compat.CoreCompatChangeRule.DisableCompatChanges;
+import static libcore.junit.util.compat.CoreCompatChangeRule.EnableCompatChanges;
+
 import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.doReturn;
@@ -27,6 +30,7 @@
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
+import android.compat.testing.PlatformCompatChangeRule;
 import android.content.ContentResolver;
 import android.content.Context;
 import android.net.nsd.NsdManager;
@@ -48,7 +52,9 @@
 
 import org.junit.After;
 import org.junit.Before;
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.TestRule;
 import org.junit.runner.RunWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Mock;
@@ -67,6 +73,8 @@
     private static final long CLEANUP_DELAY_MS = 500;
     private static final long TIMEOUT_MS = 500;
 
+    @Rule
+    public TestRule compatChangeRule = new PlatformCompatChangeRule();
     @Mock Context mContext;
     @Mock ContentResolver mResolver;
     @Mock NsdService.NsdSettings mSettings;
@@ -94,6 +102,34 @@
     }
 
     @Test
+    @DisableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
+    public void testPreSClients() {
+        when(mSettings.isEnabled()).thenReturn(true);
+        NsdService service = makeService();
+
+        // Pre S client connected, the daemon should be started.
+        NsdManager client1 = connectClient(service);
+        waitForIdle();
+        verify(mDaemon, times(1)).maybeStart();
+        verifyDaemonCommands("start-service");
+
+        NsdManager client2 = connectClient(service);
+        waitForIdle();
+        verify(mDaemon, times(1)).maybeStart();
+
+        client1.disconnect();
+        // Still 1 client remains, daemon shouldn't be stopped.
+        waitForIdle();
+        verify(mDaemon, never()).maybeStop();
+
+        client2.disconnect();
+        // All clients are disconnected, the daemon should be stopped.
+        verifyDelayMaybeStopDaemon(CLEANUP_DELAY_MS);
+        verifyDaemonCommands("stop-service");
+    }
+
+    @Test
+    @EnableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
     public void testNoDaemonStartedWhenClientsConnect() {
         when(mSettings.isEnabled()).thenReturn(true);
 
@@ -110,13 +146,12 @@
         waitForIdle();
         verify(mDaemon, never()).execute(any());
 
+        // If there is no active request, try to clean up the daemon
+        // every time the client disconnects.
         client1.disconnect();
-        // Still 1 client remains, daemon shouldn't be stopped.
-        waitForIdle();
-        verify(mDaemon, never()).maybeStop();
-
+        verifyDelayMaybeStopDaemon(CLEANUP_DELAY_MS);
+        reset(mDaemon);
         client2.disconnect();
-        // All clients are disconnected, stop the daemon after CLEANUP_DELAY_MS.
         verifyDelayMaybeStopDaemon(CLEANUP_DELAY_MS);
 
         client1.disconnect();
@@ -124,6 +159,7 @@
     }
 
     @Test
+    @EnableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
     public void testClientRequestsAreGCedAtDisconnection() {
         when(mSettings.isEnabled()).thenReturn(true);
 
@@ -169,6 +205,7 @@
     }
 
     @Test
+    @EnableCompatChanges(NsdManager.RUN_NATIVE_NSD_ONLY_IF_LEGACY_APPS)
     public void testCleanupDelayNoRequestActive() {
         when(mSettings.isEnabled()).thenReturn(true);