diff --git a/.github/workflows/coding-standards.yml b/.github/workflows/coding-standards.yml
index 636c442..d6322e5 100644
--- a/.github/workflows/coding-standards.yml
+++ b/.github/workflows/coding-standards.yml
@@ -15,6 +15,6 @@ jobs:
     name: "Coding Standards"
     uses: "doctrine/.github/.github/workflows/coding-standards.yml@1.3.0"
     with:
-      php-version: '8.0'
+      php-version: '8.1'
       composer-options: '--prefer-dist --ignore-platform-req=php'
 
diff --git a/.github/workflows/continuous-integration.yml b/.github/workflows/continuous-integration.yml
index 77642bc..c362142 100644
--- a/.github/workflows/continuous-integration.yml
+++ b/.github/workflows/continuous-integration.yml
@@ -19,18 +19,19 @@ jobs:
       fail-fast: false
       matrix:
         php-version:
-          - "8.0"
           - "8.1"
+          - "8.2"
+          - "8.3"
         dependencies:
           - "highest"
         optional-dependencies:
           - true
           - false
         include:
-          -   php-version: "8.0"
+          -   php-version: "8.1"
               dependencies: "lowest"
               optional-dependencies: false
-          -   php-version: "8.0"
+          -   php-version: "8.1"
               dependencies: "lowest"
               optional-dependencies: true
 
diff --git a/.github/workflows/php.yml b/.github/workflows/php.yml
index 6dcf060..39335a6 100644
--- a/.github/workflows/php.yml
+++ b/.github/workflows/php.yml
@@ -28,9 +28,3 @@ jobs:
 
     - name: Install dependencies
       run: composer install --prefer-dist --no-progress
-
-    # Add a test script to composer.json, for instance: "test": "vendor/bin/phpunit"
-    # Docs: https://getcomposer.org/doc/articles/scripts.md
-
-    # - name: Run test suite
-    #   run: composer run-script test
diff --git a/.github/workflows/static-analysis.yml b/.github/workflows/static-analysis.yml
index c2f179d..4a3f43c 100644
--- a/.github/workflows/static-analysis.yml
+++ b/.github/workflows/static-analysis.yml
@@ -18,7 +18,7 @@ jobs:
     steps:
       - uses: shivammathur/setup-php@15c43e89cdef867065b0213be354c2841860869e
         with:
-          php-version: '8.0'
+          php-version: '8.1'
       - uses: actions/checkout@v2
       - name: Install Dependencies
         run: composer install -q --no-ansi --no-interaction --no-scripts --no-progress --prefer-dist
diff --git a/README.md b/README.md
index 87fa5c6..a74d74d 100644
--- a/README.md
+++ b/README.md
@@ -2,7 +2,7 @@
 
 [![Build Status](https://github.com/API-Skeletons/laravel-api-problem/actions/workflows/continuous-integration.yml/badge.svg)](https://github.com/API-Skeletons/laravel-api-problem/actions/workflows/continuous-integration.yml?query=branch%3Amain)
 [![Code Coverage](https://codecov.io/gh/API-Skeletons/laravel-api-problem/branch/main/graphs/badge.svg)](https://codecov.io/gh/API-Skeletons/laravel-api-problem/branch/main)
-[![PHP Version](https://img.shields.io/badge/PHP-8.0%2b-blue)](https://img.shields.io/badge/PHP-8.0%2b-blue)
+[![PHP Version](https://img.shields.io/badge/PHP-8.1%2b-blue)](https://img.shields.io/badge/PHP-8.1%2b-blue)
 [![Total Downloads](https://poser.pugx.org/api-skeletons/laravel-api-problem/downloads)](//packagist.org/packages/api-skeletons/laravel-api-problem)
 [![License](https://poser.pugx.org/api-skeletons/laravel-api-problem/license)](//packagist.org/packages/api-skeletons/laravel-api-problem)
 
diff --git a/composer.json b/composer.json
index 3ec6748..1306688 100644
--- a/composer.json
+++ b/composer.json
@@ -16,7 +16,10 @@
         "chat": "https://gitter.im/API-Skeletons/open-source"
     },
     "config": {
-        "sort-packages": true
+        "sort-packages": true,
+        "allow-plugins": {
+            "dealerdirect/phpcodesniffer-composer-installer": true
+        }
     },
     "autoload": {
         "psr-4": {
@@ -42,16 +45,22 @@
         }
     },
     "scripts": {
-        "test": "vendor/bin/phpcs && vendor/bin/phpunit && vendor/bin/psalm"
+        "test": [
+            "vendor/bin/parallel-lint src test",
+            "vendor/bin/phpcs",
+            "vendor/bin/psalm",
+            "vendor/bin/phpunit"
+        ]
     },
     "require": {
-        "php": "^8.0",
+        "php": "^8.1",
         "doctrine/instantiator": "^1.4",
-        "laravel/framework": "^8.0||^9.0"
+        "laravel/framework": "^8.0 || ^9.0 || ^10.0 || ^11.0"
     },
     "require-dev": {
-        "doctrine/coding-standard": "^9.0",
-        "orchestra/testbench": "^6.23",
+        "doctrine/coding-standard": "^12.0",
+        "orchestra/testbench": "^7.41",
+        "php-parallel-lint/php-parallel-lint": "^1.4",
         "phpunit/phpunit": "^9.5",
         "vimeo/psalm": "^4.15"
     }
diff --git a/src/ApiProblem.php b/src/ApiProblem.php
index 49d1752..a65b16b 100644
--- a/src/ApiProblem.php
+++ b/src/ApiProblem.php
@@ -59,7 +59,7 @@ class ApiProblem
     /**
      * HTTP status for the error.
      */
-    protected ?int $status = null;
+    protected int|null $status = null;
 
     /**
      * Normalized property names for overloading.
@@ -123,7 +123,7 @@ class ApiProblem
     /**
      * Title of the error.
      */
-    protected ?string $title;
+    protected string|null $title;
 
     /**
      * Create an instance using the provided information. If nothing is
@@ -133,7 +133,7 @@ class ApiProblem
      *
      * @param string[] $additional
      */
-    public function __construct(int|string $status, string|Throwable $detail, ?string $type = null, ?string $title = null, array $additional = [])
+    public function __construct(int|string $status, string|Throwable $detail, string|null $type = null, string|null $title = null, array $additional = [])
     {
         if ($detail instanceof ProblemExceptionInterface) {
             if ($type === null) {
@@ -193,7 +193,7 @@ public function __get(string $name): mixed
 
         throw new InvalidArgumentException(sprintf(
             'Invalid property name "%s"',
-            $name
+            $name,
         ));
     }
 
@@ -277,7 +277,7 @@ protected function getDetail(): string
      * If an exception was provided, creates the status code from it;
      * otherwise, code as provided is used.
      */
-    protected function getStatus(): ?int
+    protected function getStatus(): int|null
     {
         if ($this->detail instanceof Throwable || $this->detail instanceof Exception) {
             $this->status = (int) $this->createStatusFromException();
diff --git a/src/Exception/DomainException.php b/src/Exception/DomainException.php
index fb82d92..af3b9ae 100644
--- a/src/Exception/DomainException.php
+++ b/src/Exception/DomainException.php
@@ -10,16 +10,14 @@ class DomainException extends \DomainException implements
     ExceptionInterface,
     ProblemExceptionInterface
 {
-    protected ?string $type = null;
+    protected string|null $type = null;
 
     /** @var string[] */
     protected array $details = [];
 
-    protected ?string $title = null;
+    protected string|null $title = null;
 
-    /**
-     * @param string[] $details
-     */
+    /** @param string[] $details */
     public function setAdditionalDetails(array $details): self
     {
         $this->details = $details;
@@ -46,12 +44,12 @@ public function getAdditionalDetails(): Traversable|array|null
         return $this->details;
     }
 
-    public function getType(): ?string
+    public function getType(): string|null
     {
         return $this->type;
     }
 
-    public function getTitle(): ?string
+    public function getTitle(): string|null
     {
         return $this->title;
     }
diff --git a/src/Exception/ProblemExceptionInterface.php b/src/Exception/ProblemExceptionInterface.php
index e0b8823..afa03ac 100644
--- a/src/Exception/ProblemExceptionInterface.php
+++ b/src/Exception/ProblemExceptionInterface.php
@@ -13,7 +13,7 @@ interface ProblemExceptionInterface
 {
     public function getAdditionalDetails(): array|Traversable|null;
 
-    public function getType(): ?string;
+    public function getType(): string|null;
 
-    public function getTitle(): ?string;
+    public function getTitle(): string|null;
 }