diff --git a/pom.xml b/pom.xml
index c5258e2..f7ee5dd 100644
--- a/pom.xml
+++ b/pom.xml
@@ -40,6 +40,7 @@
     <jenkins.version>${jenkins.baseline}.3</jenkins.version>
     <gitHubRepo>jenkinsci/${project.artifactId}-plugin</gitHubRepo>
     <spotless.check.skip>false</spotless.check.skip>
+    <ban-junit4-imports.skip>false</ban-junit4-imports.skip>
     <hpi.bundledArtifacts>aopalliance-repackaged,hk2-api,hk2-locator,hk2-utils,jakarta.inject,jakarta.json,jakarta.json,jakarta.json-api,jakarta.json.bind-api,jakarta.validation-api,jakarta.ws.rs-api,javassist,jersey-apache-connector,jersey-client,jersey-common,jersey-container-servlet,jersey-container-servlet-core,jersey-entity-filtering,jersey-hk2,jersey-media-jaxb,jersey-media-json-binding,jersey-media-json-jackson,jersey-media-json-jettison,jersey-media-multipart,jersey-media-sse,jersey-server,jettison,mimepull,osgi-resource-locator,yasson</hpi.bundledArtifacts>
     <hpi.strictBundledArtifacts>true</hpi.strictBundledArtifacts>
   </properties>
diff --git a/src/test/java/org/glassfish/jersey/JerseyTest.java b/src/test/java/org/glassfish/jersey/JerseyTest.java
index dd49972..99a2ae3 100644
--- a/src/test/java/org/glassfish/jersey/JerseyTest.java
+++ b/src/test/java/org/glassfish/jersey/JerseyTest.java
@@ -1,24 +1,24 @@
 package org.glassfish.jersey;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import java.net.URI;
 import javax.ws.rs.client.Client;
 import javax.ws.rs.client.ClientBuilder;
 import org.glassfish.jersey.client.ClientConfig;
-import org.junit.Rule;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 import org.jvnet.hudson.test.JenkinsRule;
-import org.jvnet.hudson.test.RealJenkinsRule;
+import org.jvnet.hudson.test.junit.jupiter.RealJenkinsExtension;
 
-public class JerseyTest {
+class JerseyTest {
 
-    @Rule
-    public RealJenkinsRule rr = new RealJenkinsRule();
+    @RegisterExtension
+    private final RealJenkinsExtension extension = new RealJenkinsExtension();
 
     @Test
-    public void json() throws Throwable {
-        rr.then(JerseyTest::_json);
+    void json() throws Throwable {
+        extension.then(JerseyTest::_json);
     }
 
     private static void _json(JenkinsRule j) throws Exception {
diff --git a/src/test/java/org/glassfish/jersey/RestEasyTest.java b/src/test/java/org/glassfish/jersey/RestEasyTest.java
index 344b15c..5e6599b 100644
--- a/src/test/java/org/glassfish/jersey/RestEasyTest.java
+++ b/src/test/java/org/glassfish/jersey/RestEasyTest.java
@@ -1,6 +1,6 @@
 package org.glassfish.jersey;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import javax.ws.rs.GET;
 import javax.ws.rs.Path;
@@ -11,18 +11,24 @@
 import org.jboss.resteasy.client.jaxrs.ResteasyClient;
 import org.jboss.resteasy.client.jaxrs.ResteasyClientBuilder;
 import org.jboss.resteasy.client.jaxrs.ResteasyWebTarget;
-import org.junit.Rule;
-import org.junit.Test;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hudson.test.JenkinsRule;
 import org.jvnet.hudson.test.TestExtension;
+import org.jvnet.hudson.test.junit.jupiter.WithJenkins;
 
-public class RestEasyTest {
+@WithJenkins
+class RestEasyTest {
 
-    @Rule
-    public JenkinsRule j = new JenkinsRule();
+    private JenkinsRule j;
+
+    @BeforeEach
+    void beforeEach(JenkinsRule rule) {
+        j = rule;
+    }
 
     @Test
-    public void withoutJackson() throws Exception {
+    void withoutJackson() throws Exception {
         ResteasyClientBuilder builder = new ResteasyClientBuilder();
         final ResteasyClient resteasyClient = builder.connectionPoolSize(60).build();
         final ResteasyWebTarget target = resteasyClient.target(j.getURL() + "jersey");
@@ -33,7 +39,7 @@ public void withoutJackson() throws Exception {
     }
 
     @Test
-    public void withJackson() throws Exception {
+    void withJackson() throws Exception {
         ResteasyClientBuilder builder = new ResteasyClientBuilder();
         final ResteasyClient resteasyClient =
                 builder.register(new JacksonFeature()).connectionPoolSize(60).build();
@@ -45,7 +51,7 @@ public void withJackson() throws Exception {
     }
 
     @Path("/employee")
-    public static interface EmployeeService {
+    public interface EmployeeService {
 
         @GET
         @Produces({MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
@@ -56,6 +62,7 @@ public static interface EmployeeService {
         String getAtAsString(@QueryParam("q") String q);
     }
 
+    @SuppressWarnings("unused")
     @TestExtension
     public static class RestEasyJerseyResource extends JerseyResource {}
 }
diff --git a/src/test/java/org/glassfish/jersey/jackson/JacksonFeatureTest.java b/src/test/java/org/glassfish/jersey/jackson/JacksonFeatureTest.java
index 2f394ee..81cd6dc 100644
--- a/src/test/java/org/glassfish/jersey/jackson/JacksonFeatureTest.java
+++ b/src/test/java/org/glassfish/jersey/jackson/JacksonFeatureTest.java
@@ -2,19 +2,19 @@
 
 import org.glassfish.jersey.client.JerseyClient;
 import org.glassfish.jersey.client.JerseyClientBuilder;
-import org.junit.Rule;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 import org.jvnet.hudson.test.JenkinsRule;
-import org.jvnet.hudson.test.RealJenkinsRule;
+import org.jvnet.hudson.test.junit.jupiter.RealJenkinsExtension;
 
-public class JacksonFeatureTest {
+class JacksonFeatureTest {
 
-    @Rule
-    public RealJenkinsRule rr = new RealJenkinsRule();
+    @RegisterExtension
+    private final RealJenkinsExtension extension = new RealJenkinsExtension();
 
     @Test
-    public void smokes() throws Throwable {
-        rr.then(JacksonFeatureTest::_smokes);
+    void smokes() throws Throwable {
+        extension.then(JacksonFeatureTest::_smokes);
     }
 
     private static void _smokes(JenkinsRule r) {