diff --git a/client/src/main/java/org/glassfish/tyrus/client/ClientManager.java b/client/src/main/java/org/glassfish/tyrus/client/ClientManager.java
index fd68e9e2..151aa248 100755
--- a/client/src/main/java/org/glassfish/tyrus/client/ClientManager.java
+++ b/client/src/main/java/org/glassfish/tyrus/client/ClientManager.java
@@ -290,31 +290,52 @@ public boolean evaluate() {
     }
 
     @Override
-    public Session connectToServer(Class annotatedEndpointClass, URI path) throws DeploymentException, IOException {
+    public Session connectToServer(final Class annotatedEndpointClass, final URI path) throws DeploymentException, IOException {
         if (annotatedEndpointClass.getAnnotation(ClientEndpoint.class) == null) {
             throw new DeploymentException(
                     String.format(
                             "Class argument in connectToServer(Class, URI) is to be annotated endpoint class. Class "
                                     + "%s does not have @ClientEndpoint", annotatedEndpointClass.getName()));
         }
-        return tryCatchInterruptedExecutionEx(() -> connectToServer(annotatedEndpointClass, null, path.toString(), true));
+        return tryCatchInterruptedExecutionEx(new SupplierWithEx<Future<Session>, DeploymentException>() {
+            @Override
+            public Future<Session> get() throws DeploymentException {
+                return connectToServer(annotatedEndpointClass, null, path.toString(), true);
+            }
+        });
     }
 
     @Override
-    public Session connectToServer(Class<? extends Endpoint> endpointClass, ClientEndpointConfig cec, URI path) throws
-            DeploymentException, IOException {
-        return tryCatchInterruptedExecutionEx(() -> connectToServer(endpointClass, cec, path.toString(), true));
+    public Session connectToServer(final Class<? extends Endpoint> endpointClass,
+                                   final ClientEndpointConfig cec,
+                                   final URI path) throws DeploymentException, IOException {
+        return tryCatchInterruptedExecutionEx(new SupplierWithEx<Future<Session>, DeploymentException>() {
+            @Override
+            public Future<Session> get() throws DeploymentException {
+                return connectToServer(endpointClass, cec, path.toString(), true);
+            }
+        });
     }
 
     @Override
-    public Session connectToServer(Endpoint endpointInstance, ClientEndpointConfig cec, URI path) throws
+    public Session connectToServer(final Endpoint endpointInstance, final ClientEndpointConfig cec, final URI path) throws
             DeploymentException, IOException {
-        return tryCatchInterruptedExecutionEx(() -> connectToServer(endpointInstance, cec, path.toString(), true));
+        return tryCatchInterruptedExecutionEx(new SupplierWithEx<Future<Session>, DeploymentException>() {
+            @Override
+            public Future<Session> get() throws DeploymentException {
+                return connectToServer(endpointInstance, cec, path.toString(), true);
+            }
+        });
     }
 
     @Override
-    public Session connectToServer(Object obj, URI path) throws DeploymentException, IOException {
-        return tryCatchInterruptedExecutionEx(() -> connectToServer(obj, null, path.toString(), true));
+    public Session connectToServer(final Object obj, final URI path) throws DeploymentException, IOException {
+        return tryCatchInterruptedExecutionEx(new SupplierWithEx<Future<Session>, DeploymentException>() {
+            @Override
+            public Future<Session> get() throws DeploymentException {
+                return connectToServer(obj, null, path.toString(), true);
+            }
+        });
     }
 
     private Session tryCatchInterruptedExecutionEx(SupplierWithEx<Future<Session>, DeploymentException> supplier)
diff --git a/core/src/main/java/org/glassfish/tyrus/core/AnnotatedEndpoint.java b/core/src/main/java/org/glassfish/tyrus/core/AnnotatedEndpoint.java
index 87f14aa3..eee3975e 100755
--- a/core/src/main/java/org/glassfish/tyrus/core/AnnotatedEndpoint.java
+++ b/core/src/main/java/org/glassfish/tyrus/core/AnnotatedEndpoint.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011, 2022 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2011, 2023 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -95,7 +95,7 @@ public static AnnotatedEndpoint fromClass(Class<?> annotatedClass, ComponentProv
                                               boolean isServerEndpoint, int incomingBufferSize, ErrorCollector
                                               collector, EndpointEventListener endpointEventListener) {
         return fromClass(annotatedClass, componentProvider, isServerEndpoint, incomingBufferSize, collector,
-                                      endpointEventListener, Collections.emptySet());
+                                      endpointEventListener, (Set<Extension>) (Set) Collections.emptySet());
     }
 
     /**
@@ -132,7 +132,7 @@ public static AnnotatedEndpoint fromInstance(
             Object annotatedInstance, ComponentProviderService componentProvider, boolean isServerEndpoint,
             int incomingBufferSize, ErrorCollector collector) {
         return fromInstance(annotatedInstance, componentProvider, isServerEndpoint, incomingBufferSize,
-                                     collector, Collections.emptySet());
+                                     collector, (Set<Extension>) (Set) Collections.emptySet());
     }
 
      /**
diff --git a/core/src/main/java/org/glassfish/tyrus/core/TyrusServerEndpointConfigurator.java b/core/src/main/java/org/glassfish/tyrus/core/TyrusServerEndpointConfigurator.java
index dbe69d7d..dc30b8d5 100644
--- a/core/src/main/java/org/glassfish/tyrus/core/TyrusServerEndpointConfigurator.java
+++ b/core/src/main/java/org/glassfish/tyrus/core/TyrusServerEndpointConfigurator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2022 Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2023 Oracle and/or its affiliates. All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0, which is available at
@@ -28,6 +28,7 @@
 import jakarta.websocket.server.ServerEndpointConfig;
 
 import org.glassfish.tyrus.core.collection.LazyValue;
+import org.glassfish.tyrus.core.collection.Value;
 import org.glassfish.tyrus.core.collection.Values;
 import org.glassfish.tyrus.core.extension.ExtendedExtension;
 import org.glassfish.tyrus.core.frame.Frame;
@@ -42,7 +43,12 @@ public class TyrusServerEndpointConfigurator extends ServerEndpointConfig.Config
     private LazyValue<ComponentProviderService> componentProviderService;
 
     public TyrusServerEndpointConfigurator() {
-        this.componentProviderService = Values.lazy(() -> ComponentProviderService.create());
+        this.componentProviderService = Values.lazy(new Value<ComponentProviderService>() {
+            @Override
+            public ComponentProviderService get() {
+                return ComponentProviderService.create();
+            }
+        });
     }
 
     @Override
diff --git a/ext/client-java8/pom.xml b/ext/client-java8/pom.xml
index 4aab416b..a188e4e3 100644
--- a/ext/client-java8/pom.xml
+++ b/ext/client-java8/pom.xml
@@ -77,6 +77,13 @@
                     <unpackBundle>true</unpackBundle>
                 </configuration>
             </plugin>
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
         </plugins>
     </build>
 
diff --git a/tests/release-test/pom.xml b/tests/release-test/pom.xml
index 9fa55b5e..d7f1a023 100644
--- a/tests/release-test/pom.xml
+++ b/tests/release-test/pom.xml
@@ -57,6 +57,13 @@
                     </includes>
                 </configuration>
             </plugin>
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
         </plugins>
     </build>
 
diff --git a/tests/tools/pom.xml b/tests/tools/pom.xml
index bc45bdaf..72d9e037 100755
--- a/tests/tools/pom.xml
+++ b/tests/tools/pom.xml
@@ -43,6 +43,13 @@
                     <unpackBundle>true</unpackBundle>
                 </configuration>
             </plugin>
+            <plugin>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
         </plugins>
     </build>