diff --git a/.github/workflows/php.yml b/.github/workflows/php.yml
index dc4557c..83591dc 100644
--- a/.github/workflows/php.yml
+++ b/.github/workflows/php.yml
@@ -12,7 +12,7 @@ jobs:
     strategy:
       matrix:
         operating-system: ['ubuntu-latest']
-        php-versions: ['8.3', '8.4']
+        php-versions: ['8.3', '8.4', '8.5']
         phpunit-versions: ['latest']
     steps:
     - name: Checkout
diff --git a/composer.json b/composer.json
index a355af8..d79f91f 100644
--- a/composer.json
+++ b/composer.json
@@ -1,6 +1,6 @@
 {
 	"name": "staffbase/plugins-sdk-php",
-	"version": "3.0.1",
+	"version": "3.0.2",
 	"type": "library",
 	"description": "Staffbase PHP SDK library for plugins.",
 	"keywords": ["staffbase", "plugins", "library", "php", "sdk"],
@@ -13,13 +13,12 @@
 		}
 	],
 	"require": {
-        "php": "^8.3 || ^8.4",
+		"php": "^8.3",
 		"lcobucci/jwt": "^5.5",
  		"lcobucci/clock": "^3.3"
 
 	},
 	"require-dev": {
-		"phpseclib/phpseclib": "^2.0",
 		"phpunit/phpunit": "^9.0"
 	},
 	"autoload": {
diff --git a/src/SSOTokenGenerator.php b/src/SSOTokenGenerator.php
index 8d6230d..59cbe6b 100644
--- a/src/SSOTokenGenerator.php
+++ b/src/SSOTokenGenerator.php
@@ -34,7 +34,7 @@ class SSOTokenGenerator
      *
      * @return string Encoded token.
      */
-    public static function createSignedTokenFromData(string $privateKey, array $tokenData, Signer $signer = null): string
+    public static function createSignedTokenFromData(string $privateKey, array $tokenData, ?Signer $signer = null): string
     {
 
         $config = Configuration::forSymmetricSigner($signer ?: new Sha256(), InMemory::plainText($privateKey));
diff --git a/src/SessionHandling/SessionHandlerTrait.php b/src/SessionHandling/SessionHandlerTrait.php
index 3d88898..2bf3c7d 100644
--- a/src/SessionHandling/SessionHandlerTrait.php
+++ b/src/SessionHandling/SessionHandlerTrait.php
@@ -116,7 +116,7 @@ public function setSessionVar($key, $val, ?string $parentKey = null): void
      * @param String|null $sessionId
      * @return bool true on success or false on failure.
      */
-    public function destroySession(String $sessionId = null): bool
+    public function destroySession(?string $sessionId = null): bool
     {
         $sessionId = $sessionId ?: $this->sessionId;
 
diff --git a/test/PluginSessionTest.php b/test/PluginSessionTest.php
index efd7c76..bc00e75 100644
--- a/test/PluginSessionTest.php
+++ b/test/PluginSessionTest.php
@@ -12,7 +12,6 @@
 namespace Staffbase\plugins\test;
 
 use ReflectionClass;
-use phpseclib\Crypt\RSA;
 use PHPUnit\Framework\TestCase;
 use SessionHandlerInterface;
 use Staffbase\plugins\sdk\Exceptions\SSOAuthenticationException;
@@ -42,11 +41,7 @@ public function __construct()
     {
 
         parent::__construct();
-        $rsa = new RSA();
-        $keypair = $rsa->createKey(2048);
-
-        $this->publicKey  = $keypair['publickey'];
-        $this->privateKey = $keypair['privatekey'];
+        [$this->publicKey, $this->privateKey] = SSOTestData::createKeyPair();
 
         $this->tokenData = SSOTestData::getTokenData();
         $this->token = SSOTokenGenerator::createSignedTokenFromData($this->privateKey, $this->tokenData);
@@ -61,7 +56,7 @@ public function __construct()
      * @param string|null $queryParamJwt JWT query param emulation
      * @param boolean $clearSession optionally clear out the $_SESSION array
      */
-    private function setupEnvironment(string $queryParamPid = null, string $queryParamJwt = null, bool $clearSession = true)
+    private function setupEnvironment(?string $queryParamPid = null, ?string $queryParamJwt = null, bool $clearSession = true)
     {
 
         $_REQUEST[PluginSession::QUERY_PARAM_PID] = $queryParamPid;
diff --git a/test/SSOData/SSODataTest.php b/test/SSOData/SSODataTest.php
index 7a825ac..c50188f 100644
--- a/test/SSOData/SSODataTest.php
+++ b/test/SSOData/SSODataTest.php
@@ -91,15 +91,15 @@ public function testIsEditorReturnsCorrectValues(): void
     {
 
         $map = [
-            null => false,
-            '' => false,
-            'use' => false,
-            'edito' => false,
-            'user' => false,
-            'editor' => true,
+            [null, false],
+            ['', false],
+            ['use', false],
+            ['edito', false],
+            ['user', false],
+            ['editor', true],
         ];
 
-        foreach ($map as $arg => $expect) {
+        foreach ($map as [$arg, $expect]) {
             $tokenData = SSOTestData::getTokenData();
             $tokenData[SSOTestData::CLAIM_USER_ROLE] = $arg;
 
diff --git a/test/SSOTestData.php b/test/SSOTestData.php
index f7b8692..ac79cab 100644
--- a/test/SSOTestData.php
+++ b/test/SSOTestData.php
@@ -33,6 +33,22 @@ class SSOTestData
     private const CLAIM_USER_LOCALE                 = 'locale';
     private const CLAIM_USER_TAGS                   = 'tags';
 
+    /**
+     * Create an RSA-256 key pair in PEM format.
+     *
+     * @return array{0: string, 1: string} public key and private key
+     */
+    public static function createKeyPair(): array
+    {
+        $key = openssl_pkey_new([
+            'private_key_bits' => 2048,
+            'private_key_type' => OPENSSL_KEYTYPE_RSA,
+        ]);
+        openssl_pkey_export($key, $privateKey);
+
+        return [openssl_pkey_get_details($key)['key'], $privateKey];
+    }
+
     /**
      * Create test data for a token.
      *
diff --git a/test/SSOTokenTest.php b/test/SSOTokenTest.php
index ec39aa5..2cf5e3b 100644
--- a/test/SSOTokenTest.php
+++ b/test/SSOTokenTest.php
@@ -12,7 +12,6 @@
 namespace Staffbase\plugins\test;
 
 use DateTimeImmutable;
-use phpseclib\Crypt\RSA;
 use PHPUnit\Framework\TestCase;
 use ReflectionClass;
 use Staffbase\plugins\sdk\Exceptions\SSOAuthenticationException;
@@ -37,11 +36,7 @@ class SSOTokenTest extends TestCase
     public function setUp(): void
     {
 
-        $rsa = new RSA();
-        $keypair = $rsa->createKey(2048);
-
-        $this->publicKey  = $keypair['publickey'];
-        $this->privateKey = $keypair['privatekey'];
+        [$this->publicKey, $this->privateKey] = SSOTestData::createKeyPair();
     }
 
     /**