diff --git a/.github/workflows/analyzers.yaml b/.github/workflows/analyzers.yaml
index b67d45e..8670bcf 100644
--- a/.github/workflows/analyzers.yaml
+++ b/.github/workflows/analyzers.yaml
@@ -7,7 +7,8 @@ jobs:
         strategy:
             matrix:
                 operating-system: [ubuntu-latest]
-                php-versions: ['8.1', '8.2', '8.3']
+                php-versions: ['8.2', '8.3', '8.4']
+                composer-options: ['--ignore-platform-req=php+']
             fail-fast: false
         name: PHP ${{ matrix.php-versions }} @ ${{ matrix.operating-system }}
         steps:
diff --git a/.github/workflows/code-style.yaml b/.github/workflows/code-style.yaml
index 089eaa5..8600cb5 100644
--- a/.github/workflows/code-style.yaml
+++ b/.github/workflows/code-style.yaml
@@ -7,7 +7,8 @@ jobs:
         strategy:
             matrix:
                 operating-system: [ubuntu-latest]
-                php-versions: ['8.1', '8.2', '8.3']
+                php-versions: [ '8.2', '8.3', '8.4' ]
+                composer-options: [ '--ignore-platform-req=php+' ]
             fail-fast: false
         name: PHP ${{ matrix.php-versions }} @ ${{ matrix.operating-system }}
         steps:
diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
index 7970d91..06eb08e 100644
--- a/.github/workflows/tests.yaml
+++ b/.github/workflows/tests.yaml
@@ -7,7 +7,8 @@ jobs:
         strategy:
             matrix:
                 operating-system: [ubuntu-latest]
-                php-versions: ['8.1', '8.2', '8.3']
+                php-versions: [ '8.2', '8.3', '8.4' ]
+                composer-options: [ '--ignore-platform-req=php+' ]
             fail-fast: false
         name: PHP ${{ matrix.php-versions }} @ ${{ matrix.operating-system }}
         steps:
@@ -20,6 +21,6 @@ jobs:
                   tools: 'composer:v2'
                   extensions: pcov, mbstring, posix, dom, soap
             - name: Install dependencies
-              run: composer update --prefer-dist --no-progress --no-suggest
+              run: composer update --prefer-dist --no-progress --no-suggest ${{ matrix.composer-options }}
             - name: Run the tests
               run: ./vendor/bin/phpunit
diff --git a/.phive/phars.xml b/.phive/phars.xml
index e3b38d5..4aa93da 100644
--- a/.phive/phars.xml
+++ b/.phive/phars.xml
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phive xmlns="https://phar.io/phive">
-  <phar name="php-cs-fixer" version="^3.58.1" installed="3.58.1" location="./tools/php-cs-fixer.phar" copy="true"/>
+  <phar name="php-cs-fixer" version="^3.13.0" installed="3.64.0" location="./tools/php-cs-fixer.phar" copy="true"/>
 </phive>
diff --git a/.php-cs-fixer.dist.php b/.php-cs-fixer.dist.php
index b2fc9eb..7faf356 100644
--- a/.php-cs-fixer.dist.php
+++ b/.php-cs-fixer.dist.php
@@ -53,5 +53,6 @@
         'static_lambda' => true,
         'strict_comparison' => true,
         'strict_param' => true,
+        'nullable_type_declaration_for_default_null_value' => true,
     ])
 ;
diff --git a/composer.json b/composer.json
index ba4a049..7df4df9 100644
--- a/composer.json
+++ b/composer.json
@@ -20,14 +20,14 @@
         }
     ],
     "require": {
-        "php": "~8.1.0 || ~8.2.0 || ~8.3.0",
-        "php-soap/engine": "^2.9.0",
+        "php": "~8.2.0 || ~8.3.0 || ~8.4.0",
+        "php-soap/engine": "^2.13.0",
         "psr/cache": "^3.0",
         "psr/cache-implementation": "^3.0"
     },
     "require-dev": {
         "phpunit/phpunit": "^10.0",
-        "vimeo/psalm": "^5.9",
+        "vimeo/psalm": "^5.26",
         "symfony/cache": "^7.0 || ^6.4"
     }
 }
diff --git a/tools/php-cs-fixer.phar b/tools/php-cs-fixer.phar
index efc1559..d071fa5 100755
Binary files a/tools/php-cs-fixer.phar and b/tools/php-cs-fixer.phar differ