diff --git a/backend/src/test/java/com/stackup/stackup/session/application/SessionFeedbackRequesterTest.java b/backend/src/test/java/com/stackup/stackup/session/application/SessionFeedbackRequesterTest.java
index 9f39a6a9..a5247e91 100644
--- a/backend/src/test/java/com/stackup/stackup/session/application/SessionFeedbackRequesterTest.java
+++ b/backend/src/test/java/com/stackup/stackup/session/application/SessionFeedbackRequesterTest.java
@@ -78,7 +78,7 @@ void onSessionEnded_publishesGenerateFeedback() {
         assertThat(summary.analyzedMessageCount()).isEqualTo(2);
         assertThat(summary.averageSpeakingRateWpm()).isEqualTo(150.0);
         assertThat(summary.totalSilenceDurationSec()).isEqualTo(3.5);
-        assertThat(summary.fillerWordCounts()).containsExactlyEntriesOf(java.util.Map.of(
+        assertThat(summary.fillerWordCounts()).containsAllEntriesOf(java.util.Map.of(
             "like", 1,
             "uh", 1,
             "um", 5
diff --git a/backend/src/test/java/com/stackup/stackup/session/application/TtsCallbackServiceTest.java b/backend/src/test/java/com/stackup/stackup/session/application/TtsCallbackServiceTest.java
index dd8ba1b7..6f2439c1 100644
--- a/backend/src/test/java/com/stackup/stackup/session/application/TtsCallbackServiceTest.java
+++ b/backend/src/test/java/com/stackup/stackup/session/application/TtsCallbackServiceTest.java
@@ -23,6 +23,7 @@
 import com.stackup.stackup.session.domain.TtsStatus;
 import com.stackup.stackup.user.domain.User;
 import java.util.Optional;
+import java.util.function.Predicate;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.InjectMocks;
@@ -58,9 +59,9 @@ void apply_successStoresTtsFieldsWithoutChangingMessageStatus() {
         assertThat(question.getTtsAudioPath()).isEqualTo("interview/tts/50/100.mp3");
         assertThat(question.getTtsDurationSec()).isEqualTo(2.4);
         assertThat(MessageResult.of(question).ttsAudioPath()).isEqualTo("interview/tts/50/100.mp3");
-        verify(events).publishEvent(argThat(event ->
+        verify(events).publishEvent(argThatObject(event ->
             isNotice(event, RealtimeNotifyEvent.Channel.SESSION, 50L)));
-        verify(events).publishEvent(argThat(event ->
+        verify(events).publishEvent(argThatObject(event ->
             isNotice(event, RealtimeNotifyEvent.Channel.USER, 1L)));
         verify(processedMessageRepository).save(any(ProcessedMessage.class));
     }
@@ -81,7 +82,7 @@ void apply_failedMarksOnlyTtsFailedAndLeavesQuestionUsable() {
         assertThat(question.getTtsStatus()).isEqualTo(TtsStatus.FAILED);
         assertThat(question.getContent()).isEqualTo("Q?");
         assertThat(question.getTtsAudioPath()).isNull();
-        verify(events).publishEvent(argThat(event ->
+        verify(events).publishEvent(argThatObject(event ->
             isNotice(event, RealtimeNotifyEvent.Channel.SESSION, 50L)));
         verify(processedMessageRepository).save(any(ProcessedMessage.class));
     }
@@ -145,6 +146,10 @@ private boolean isNotice(Object event, RealtimeNotifyEvent.Channel channel, Long
             && realtimeNotifyEvent.type() == SseEventType.SESSION_MESSAGE;
     }
 
+    private Object argThatObject(Predicate<Object> predicate) {
+        return argThat(predicate::test);
+    }
+
     private InterviewSession sessionFixture(Long id) {
         User user = User.createGithubUser(1L, "u", null, null, "t");
         ReflectionTestUtils.setField(user, "id", 1L);