diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index a4bcf71..8555965 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -13,6 +13,7 @@ jobs:
     strategy:
       matrix:
         php:
+          - 8.4
           - 8.3
           - 8.2
           - 8.1
diff --git a/composer.json b/composer.json
index 9299d77..75a3141 100644
--- a/composer.json
+++ b/composer.json
@@ -14,12 +14,12 @@
         "php": ">=5.3",
         "evenement/evenement": "^3.0 || ^2.0 || ^1.0",
         "react/event-loop": "^1.2",
-        "react/promise": "^3.0 || ^2.9 || ^1.1",
-        "react/socket": "^1.14"
+        "react/promise": "^3.2 || ^2.9 || ^1.1",
+        "react/socket": "^1.16"
     },
     "require-dev": {
         "phpunit/phpunit": "^9.6 || ^5.7 || ^4.8.36",
-        "react/async": "^4.2 || ^3.2 || ^2.2"
+        "react/async": "^4.3 || ^3.2 || ^2.2"
     },
     "autoload": {
         "psr-4": {
diff --git a/src/Client.php b/src/Client.php
index 98307cd..ffc2aa6 100644
--- a/src/Client.php
+++ b/src/Client.php
@@ -33,8 +33,16 @@ class Client extends EventEmitter
 
     private $actionId = 0;
 
-    public function __construct(ConnectionInterface $stream, Parser $parser = null)
+    /**
+     * @param ConnectionInterface $stream
+     * @param ?Parser $parser
+     */
+    public function __construct(ConnectionInterface $stream, $parser = null)
     {
+        if ($parser !== null && !$parser instanceof Parser) { // manual type check to support legacy PHP < 7.1
+            throw new \InvalidArgumentException('Argument #2 ($parser) expected null|Clue\React\Ami\Protocol\Parser');
+        }
+
         if ($parser === null) {
             $parser = new Parser();
         }
diff --git a/src/Factory.php b/src/Factory.php
index 1169a27..b8ee591 100644
--- a/src/Factory.php
+++ b/src/Factory.php
@@ -43,8 +43,19 @@ class Factory
 {
     private $connector;
 
-    public function __construct(LoopInterface $loop = null, ConnectorInterface $connector = null)
+    /**
+     * @param ?LoopInterface $loop
+     * @param ?ConnectorInterface $connector
+     */
+    public function __construct($loop = null, $connector = null)
     {
+        if ($loop !== null && !$loop instanceof LoopInterface) { // manual type check to support legacy PHP < 7.1
+            throw new \InvalidArgumentException('Argument #1 ($loop) expected null|React\EventLoop\LoopInterface');
+        }
+        if ($connector !== null && !$connector instanceof ConnectorInterface) { // manual type check to support legacy PHP < 7.1
+            throw new \InvalidArgumentException('Argument #2 ($connector) expected null|React\Socket\ConnectorInterface');
+        }
+
         if ($connector === null) {
             $connector = new Connector(array(), $loop);
         }
diff --git a/tests/ClientTest.php b/tests/ClientTest.php
index 44ce726..4b93506 100644
--- a/tests/ClientTest.php
+++ b/tests/ClientTest.php
@@ -43,6 +43,12 @@ public function testUnexpectedResponseEmitsErrorAndClosesClient()
         $client->handleMessage(new Response(array('ActionID' => 1)));
     }
 
+    public function testCtorThrowsForInvalidParser()
+    {
+        $this->setExpectedException('InvalidArgumentException', 'Argument #2 ($parser) expected null|Clue\React\Ami\Protocol\Parser');
+        new Client($this->createStreamMock(), 'parser');
+    }
+
     private function createStreamMock()
     {
         if (method_exists('PHPUnit\Framework\MockObject\MockBuilder', 'onlyMethods')) {
diff --git a/tests/FactoryTest.php b/tests/FactoryTest.php
index 2fe2ff7..607c899 100644
--- a/tests/FactoryTest.php
+++ b/tests/FactoryTest.php
@@ -31,6 +31,18 @@ public function testDefaultCtorCreatesConnectorAutomatically()
         $this->assertInstanceOf('React\Socket\Connector', $connector);
     }
 
+    public function testCtorThrowsForInvalidLoop()
+    {
+        $this->setExpectedException('InvalidArgumentException', 'Argument #1 ($loop) expected null|React\EventLoop\LoopInterface');
+        new Factory('loop');
+    }
+
+    public function testCtorThrowsForInvalidConnector()
+    {
+        $this->setExpectedException('InvalidArgumentException', 'Argument #2 ($connector) expected null|React\Socket\ConnectorInterface');
+        new Factory(null, 'connector');
+    }
+
     public function testCreateClientUsesDefaultPortForTcpConnection()
     {
         $promise = new Promise(function () { });