diff --git a/spring-boot-modules/spring-boot-4/pom.xml b/spring-boot-modules/spring-boot-4/pom.xml
index 1fa59f2fb97e..2ca2a97240a9 100644
--- a/spring-boot-modules/spring-boot-4/pom.xml
+++ b/spring-boot-modules/spring-boot-4/pom.xml
@@ -42,6 +42,7 @@
             <groupId>org.projectlombok</groupId>
             <artifactId>lombok</artifactId>
             <optional>true</optional>
+            <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>org.mapstruct</groupId>
@@ -145,6 +146,10 @@
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>21</source> <!-- Or 16+ if Java 21 is too aggressive -->
+                    <target>21</target>
+                </configuration>
             </plugin>
         </plugins>
     </build>
diff --git a/spring-boot-modules/spring-boot-4/src/test/java/com/baeldung/spring/resttestclient/RestTestClientTest.java b/spring-boot-modules/spring-boot-4/src/test/java/com/baeldung/spring/resttestclient/RestTestClientTest.java
new file mode 100644
index 000000000000..5e36a367875a
--- /dev/null
+++ b/spring-boot-modules/spring-boot-4/src/test/java/com/baeldung/spring/resttestclient/RestTestClientTest.java
@@ -0,0 +1,26 @@
+package com.baeldung.spring.resttestclient;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.http.MediaType;
+import org.springframework.test.web.servlet.client.RestTestClient;
+
+public class RestTestClientTest {
+
+    RestTestClient client = RestTestClient.bindToServer()
+        .baseUrl("http://localhost:8080")
+        .build();
+
+    @Test
+    void should() {
+        System.out.println("Foo");
+
+        client.get()
+            .uri("/persons/1")
+            .accept(MediaType.APPLICATION_JSON)
+            .exchange()
+            .expectStatus()
+            .isOk()
+            .expectHeader()
+            .contentType(MediaType.APPLICATION_JSON);
+    }
+}