diff --git a/app/src/testDemo/kotlin/com/google/samples/apps/nowinandroid/ui/NiaAppStateTest.kt b/app/src/testDemo/kotlin/com/google/samples/apps/nowinandroid/ui/NiaAppStateTest.kt
index c6ddb54fb..e6d067b46 100644
--- a/app/src/testDemo/kotlin/com/google/samples/apps/nowinandroid/ui/NiaAppStateTest.kt
+++ b/app/src/testDemo/kotlin/com/google/samples/apps/nowinandroid/ui/NiaAppStateTest.kt
@@ -29,6 +29,7 @@ import androidx.navigation.testing.TestNavHostController
 import com.google.samples.apps.nowinandroid.core.data.repository.CompositeUserNewsResourceRepository
 import com.google.samples.apps.nowinandroid.core.testing.repository.TestNewsRepository
 import com.google.samples.apps.nowinandroid.core.testing.repository.TestUserDataRepository
+import com.google.samples.apps.nowinandroid.core.testing.util.MainDispatcherRule
 import com.google.samples.apps.nowinandroid.core.testing.util.TestNetworkMonitor
 import com.google.samples.apps.nowinandroid.core.testing.util.TestTimeZoneMonitor
 import dagger.hilt.android.testing.HiltAndroidTest
@@ -54,16 +55,19 @@ import kotlin.test.assertTrue
 @HiltAndroidTest
 class NiaAppStateTest {
 
-    @get:Rule
+    @get:Rule(0)
     val composeTestRule = createComposeRule()
 
+    @get:Rule(1)
+    val mainDispatcherRule = MainDispatcherRule()
+
     // Create the test dependencies.
     private val networkMonitor = TestNetworkMonitor()
 
     private val timeZoneMonitor = TestTimeZoneMonitor()
 
     private val userNewsResourceRepository =
-        CompositeUserNewsResourceRepository(TestNewsRepository(), TestUserDataRepository())
+        CompositeUserNewsResourceRepository(TestNewsRepository(), TestUserDataRepository(), mainDispatcherRule.testDispatcher)
 
     // Subject under test.
     private lateinit var state: NiaAppState
diff --git a/core/data/src/test/kotlin/com/google/samples/apps/nowinandroid/core/data/CompositeUserNewsResourceRepositoryTest.kt b/core/data/src/test/kotlin/com/google/samples/apps/nowinandroid/core/data/CompositeUserNewsResourceRepositoryTest.kt
index 05811f4be..b1920db4f 100644
--- a/core/data/src/test/kotlin/com/google/samples/apps/nowinandroid/core/data/CompositeUserNewsResourceRepositoryTest.kt
+++ b/core/data/src/test/kotlin/com/google/samples/apps/nowinandroid/core/data/CompositeUserNewsResourceRepositoryTest.kt
@@ -24,20 +24,26 @@ import com.google.samples.apps.nowinandroid.core.model.data.mapToUserNewsResourc
 import com.google.samples.apps.nowinandroid.core.testing.repository.TestNewsRepository
 import com.google.samples.apps.nowinandroid.core.testing.repository.TestUserDataRepository
 import com.google.samples.apps.nowinandroid.core.testing.repository.emptyUserData
+import com.google.samples.apps.nowinandroid.core.testing.util.MainDispatcherRule
 import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.test.runTest
 import kotlinx.datetime.Instant
+import org.junit.Rule
 import org.junit.Test
 import kotlin.test.assertEquals
 
 class CompositeUserNewsResourceRepositoryTest {
 
+    @get:Rule
+    val dispatcherRule = MainDispatcherRule()
+
     private val newsRepository = TestNewsRepository()
     private val userDataRepository = TestUserDataRepository()
 
     private val userNewsResourceRepository = CompositeUserNewsResourceRepository(
         newsRepository = newsRepository,
         userDataRepository = userDataRepository,
+        defaultDispatcher = dispatcherRule.testDispatcher,
     )
 
     @Test
diff --git a/core/domain/src/test/kotlin/com/google/samples/apps/nowinandroid/core/domain/GetFollowableTopicsUseCaseTest.kt b/core/domain/src/test/kotlin/com/google/samples/apps/nowinandroid/core/domain/GetFollowableTopicsUseCaseTest.kt
index 42a31f858..cd3890104 100644
--- a/core/domain/src/test/kotlin/com/google/samples/apps/nowinandroid/core/domain/GetFollowableTopicsUseCaseTest.kt
+++ b/core/domain/src/test/kotlin/com/google/samples/apps/nowinandroid/core/domain/GetFollowableTopicsUseCaseTest.kt
@@ -39,6 +39,7 @@ class GetFollowableTopicsUseCaseTest {
     val useCase = GetFollowableTopicsUseCase(
         topicsRepository,
         userDataRepository,
+        mainDispatcherRule.testDispatcher,
     )
 
     @Test
diff --git a/core/testing/src/main/kotlin/com/google/samples/apps/nowinandroid/core/testing/util/MainDispatcherRule.kt b/core/testing/src/main/kotlin/com/google/samples/apps/nowinandroid/core/testing/util/MainDispatcherRule.kt
index 666c4edd4..5d68f6e2a 100644
--- a/core/testing/src/main/kotlin/com/google/samples/apps/nowinandroid/core/testing/util/MainDispatcherRule.kt
+++ b/core/testing/src/main/kotlin/com/google/samples/apps/nowinandroid/core/testing/util/MainDispatcherRule.kt
@@ -30,7 +30,11 @@ import org.junit.runner.Description
  * for the duration of the test.
  */
 class MainDispatcherRule(
-    private val testDispatcher: TestDispatcher = UnconfinedTestDispatcher(),
+    /**
+     * Expose testDispatcher to share the scheduler to the test.
+     * See more in [Documentation](https://developer.android.com/kotlin/coroutines/test#injecting-test-dispatchers)
+     */
+    val testDispatcher: TestDispatcher = UnconfinedTestDispatcher(),
 ) : TestWatcher() {
     override fun starting(description: Description) = Dispatchers.setMain(testDispatcher)
 
diff --git a/feature/bookmarks/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/bookmarks/BookmarksViewModelTest.kt b/feature/bookmarks/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/bookmarks/BookmarksViewModelTest.kt
index aa42adae2..057996fa8 100644
--- a/feature/bookmarks/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/bookmarks/BookmarksViewModelTest.kt
+++ b/feature/bookmarks/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/bookmarks/BookmarksViewModelTest.kt
@@ -48,6 +48,7 @@ class BookmarksViewModelTest {
     private val userNewsResourceRepository = CompositeUserNewsResourceRepository(
         newsRepository = newsRepository,
         userDataRepository = userDataRepository,
+        dispatcherRule.testDispatcher,
     )
     private lateinit var viewModel: BookmarksViewModel
 
diff --git a/feature/foryou/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/foryou/ForYouViewModelTest.kt b/feature/foryou/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/foryou/ForYouViewModelTest.kt
index 812544c0c..e9208efe2 100644
--- a/feature/foryou/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/foryou/ForYouViewModelTest.kt
+++ b/feature/foryou/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/foryou/ForYouViewModelTest.kt
@@ -65,11 +65,13 @@ class ForYouViewModelTest {
     private val userNewsResourceRepository = CompositeUserNewsResourceRepository(
         newsRepository = newsRepository,
         userDataRepository = userDataRepository,
+        defaultDispatcher = mainDispatcherRule.testDispatcher,
     )
 
     private val getFollowableTopicsUseCase = GetFollowableTopicsUseCase(
         topicsRepository = topicsRepository,
         userDataRepository = userDataRepository,
+        defaultDispatcher = mainDispatcherRule.testDispatcher,
     )
 
     private val savedStateHandle = SavedStateHandle()
diff --git a/feature/interests/src/test/kotlin/com/google/samples/apps/nowinandroid/interests/InterestsViewModelTest.kt b/feature/interests/src/test/kotlin/com/google/samples/apps/nowinandroid/interests/InterestsViewModelTest.kt
index cdf21f325..c1a5befdc 100644
--- a/feature/interests/src/test/kotlin/com/google/samples/apps/nowinandroid/interests/InterestsViewModelTest.kt
+++ b/feature/interests/src/test/kotlin/com/google/samples/apps/nowinandroid/interests/InterestsViewModelTest.kt
@@ -59,6 +59,7 @@ class InterestsViewModelTest {
     private val getFollowableTopicsUseCase = GetFollowableTopicsUseCase(
         topicsRepository = topicsRepository,
         userDataRepository = userDataRepository,
+        defaultDispatcher = mainDispatcherRule.testDispatcher,
     )
     private lateinit var viewModel: InterestsViewModel
 
diff --git a/feature/search/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchViewModelTest.kt b/feature/search/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchViewModelTest.kt
index 1b866cec2..9e5b5b179 100644
--- a/feature/search/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchViewModelTest.kt
+++ b/feature/search/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/search/SearchViewModelTest.kt
@@ -57,6 +57,7 @@ class SearchViewModelTest {
     private val getSearchContentsUseCase = GetSearchContentsUseCase(
         searchContentsRepository = searchContentsRepository,
         userDataRepository = userDataRepository,
+        dispatcherRule.testDispatcher,
     )
     private val recentSearchRepository = TestRecentSearchRepository()
     private val getRecentQueryUseCase = GetRecentSearchQueriesUseCase(recentSearchRepository)
diff --git a/feature/topic/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/topic/TopicViewModelTest.kt b/feature/topic/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/topic/TopicViewModelTest.kt
index 58242110d..f1e1e9d1c 100644
--- a/feature/topic/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/topic/TopicViewModelTest.kt
+++ b/feature/topic/src/test/kotlin/com/google/samples/apps/nowinandroid/feature/topic/TopicViewModelTest.kt
@@ -52,6 +52,7 @@ class TopicViewModelTest {
     private val userNewsResourceRepository = CompositeUserNewsResourceRepository(
         newsRepository = newsRepository,
         userDataRepository = userDataRepository,
+        defaultDispatcher = dispatcherRule.testDispatcher,
     )
     private lateinit var viewModel: TopicViewModel