diff --git a/plugin-api-test-client/.idea/compiler.xml b/plugin-api-test-client/.idea/compiler.xml
index 9d8397ba..d7c2d084 100644
--- a/plugin-api-test-client/.idea/compiler.xml
+++ b/plugin-api-test-client/.idea/compiler.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="CompilerConfiguration">
-    <bytecodeTargetLevel target="18">
+    <bytecodeTargetLevel target="21">
       <module name="intellij-plugin-parent.plugin-api-test-client" target="18" />
       <module name="intellij-plugin-parent.plugin-api-test-client.main" target="18" />
       <module name="intellij-plugin-parent.plugin-api-test-client.test" target="18" />
diff --git a/plugin-api-test-client/.idea/gradle.xml b/plugin-api-test-client/.idea/gradle.xml
index 37ac4c0d..701a27c3 100644
--- a/plugin-api-test-client/.idea/gradle.xml
+++ b/plugin-api-test-client/.idea/gradle.xml
@@ -5,7 +5,7 @@
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
         <option name="externalProjectPath" value="$PROJECT_DIR$" />
-        <option name="gradleJvm" value="18" />
+        <option name="gradleJvm" value="jbr-21" />
         <option name="modules">
           <set>
             <option value="$PROJECT_DIR$" />
diff --git a/plugin-api-test-client/.idea/misc.xml b/plugin-api-test-client/.idea/misc.xml
index b5b0f5fa..4e97810d 100644
--- a/plugin-api-test-client/.idea/misc.xml
+++ b/plugin-api-test-client/.idea/misc.xml
@@ -4,5 +4,5 @@
   <component name="FrameworkDetectionExcludesConfiguration">
     <file type="web" url="file://$PROJECT_DIR$/.." />
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_18" default="true" project-jdk-name="18" project-jdk-type="JavaSDK" />
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_21" default="true" project-jdk-name="jbr-21" project-jdk-type="JavaSDK" />
 </project>
\ No newline at end of file
diff --git a/plugin-api-test-client/build.gradle.kts b/plugin-api-test-client/build.gradle.kts
index cddb9f05..ea7a6603 100644
--- a/plugin-api-test-client/build.gradle.kts
+++ b/plugin-api-test-client/build.gradle.kts
@@ -14,7 +14,7 @@ repositories {
 dependencies {
     implementation("org.springframework.boot:spring-boot-starter-web:3.4.2")
     implementation("com.fasterxml.jackson.core:jackson-databind:2.18.2")
-    implementation("com.vaadin:vaadin-core:24.6.5")
+    implementation("com.vaadin:vaadin-core:24.7.4")
     testImplementation("org.springframework.boot:spring-boot-starter-test:3.4.2")
 }
 
diff --git a/plugin-api-test-client/src/main/java/com/vaadin/plugin/Client.java b/plugin-api-test-client/src/main/java/com/vaadin/plugin/Client.java
index 2e24d566..2f270dbb 100644
--- a/plugin-api-test-client/src/main/java/com/vaadin/plugin/Client.java
+++ b/plugin-api-test-client/src/main/java/com/vaadin/plugin/Client.java
@@ -52,13 +52,16 @@ public RestClient.ResponseSpec delete(Path path) throws IOException {
         return send("delete", new Message.DeleteMessage(path.toString()));
     }
 
+    public RestClient.ResponseSpec heartbeat() throws IOException {
+        return send("heartbeat", new Message.HeartbeatMessage());
+    }
+
     private RestClient.ResponseSpec send(String command, Object data) throws JsonProcessingException {
         Message.CopilotRestRequest message = new Message.CopilotRestRequest(command, projectBasePath, data);
         String body = new ObjectMapper().writeValueAsString(message);
-        org.springframework.web.client.RestClient.ResponseSpec response = org.springframework.web.client.RestClient.create().post()
+        return org.springframework.web.client.RestClient.create().post()
                 .uri(endpoint).contentType(MediaType.APPLICATION_JSON)
                 .body(body).retrieve();
-        return response;
     }
 
 }
diff --git a/plugin-api-test-client/src/main/java/com/vaadin/plugin/Message.java b/plugin-api-test-client/src/main/java/com/vaadin/plugin/Message.java
index 95c100bf..d127fc54 100644
--- a/plugin-api-test-client/src/main/java/com/vaadin/plugin/Message.java
+++ b/plugin-api-test-client/src/main/java/com/vaadin/plugin/Message.java
@@ -1,6 +1,7 @@
 package com.vaadin.plugin;
 
 import java.util.List;
+import java.util.Set;
 
 public class Message {
 
@@ -31,4 +32,10 @@ record CompileMessage(List<String> files) {
     record DeleteMessage(String file) {
     }
 
+    record HeartbeatMessage() {
+    }
+
+    record HeartbeatResponse(Boolean hasCompilationError, Set<String> filesContainCompilationError) {
+    }
+
 }
diff --git a/plugin-api-test-client/src/test/java/com/vaadin/plugin/PluginApiTests.java b/plugin-api-test-client/src/test/java/com/vaadin/plugin/PluginApiTests.java
index ec884ea9..757fddb6 100644
--- a/plugin-api-test-client/src/test/java/com/vaadin/plugin/PluginApiTests.java
+++ b/plugin-api-test-client/src/test/java/com/vaadin/plugin/PluginApiTests.java
@@ -14,10 +14,7 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.attribute.FileAttribute;
-import java.util.Base64;
-import java.util.Map;
-import java.util.Properties;
-import java.util.UUID;
+import java.util.*;
 import java.util.function.Predicate;
 
 @SpringBootTest(classes = {SpringBootApplication.class})
@@ -33,6 +30,12 @@ protected Path getTestResourcePath(String childPath) {
                 .resolve(childPath);
     }
 
+    protected Path getSourcePath(String childPath) {
+        return Path.of(projectBasePath)
+                .resolve("src/main/java")
+                .resolve(childPath);
+    }
+
     @BeforeAll
     public static void beforeAll() throws IOException {
         projectBasePath = Path.of(System.getProperty("user.dir")).toString();
@@ -121,6 +124,38 @@ public void testUndoRedo() throws IOException, InterruptedException {
         Assertions.assertFalse(performed);
     }
 
+    // Run using Debug to trigger compile on save
+    @Test
+    public void testHeartbeat() throws IOException, InterruptedException {
+        var response = client.heartbeat();
+        var body = response.body(Message.HeartbeatResponse.class);
+        Assertions.assertFalse(body.hasCompilationError());
+        Assertions.assertEquals(Collections.EMPTY_SET, body.filesContainCompilationError());
+
+        var filePath = getSourcePath("com/vaadin/plugin/Test.java");
+        filePath.toFile().deleteOnExit();
+
+        response = client.write(filePath, "package com.vaadin.plugin;\n" +
+                "\n" +
+                "public class Test {\n" +
+                "asdasdasd" +
+                "}");
+        assertHttpOk(response);
+        Thread.sleep(2000);
+
+        for (int i = 0 ; i < 10 ; ++i) {
+            response = client.heartbeat();
+            body = response.body(Message.HeartbeatResponse.class);
+            if (body.hasCompilationError()) {
+                Assertions.assertEquals(Collections.EMPTY_SET, body.filesContainCompilationError());
+                return;
+            }
+            Thread.sleep(2000);
+        }
+
+        Assertions.fail("No compilation error received");
+    }
+
     // add more tests when needed
 
     private void assertNewFileCreated(Path file) {