diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b88998f..429673a 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         operating-system: [ ubuntu-latest ]
-        php-versions: [ '8.1', '8.2', '8.3', '8.4' ]
+        php-versions: [ '8.2', '8.3', '8.4', '8.5' ]
     name: PHP ${{ matrix.php-versions }} Test on ${{ matrix.operating-system }}
 
     steps:
diff --git a/LICENSE b/LICENSE
index bfcf021..2013f40 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2025 odan
+Copyright (c) 2026 odan
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/README.md b/README.md
index ff7c9c0..80289a3 100644
--- a/README.md
+++ b/README.md
@@ -29,7 +29,7 @@ responses and many other things.
 
 ## Requirements
 
-* PHP 8.1 - 8.4
+* PHP 8.2 - 8.5
 
 ## Installation
 
diff --git a/composer.json b/composer.json
index 08698e0..b94d321 100644
--- a/composer.json
+++ b/composer.json
@@ -16,12 +16,12 @@
     ],
     "homepage": "https://github.com/selective-php/transformer",
     "require": {
-        "php": "8.1.* || 8.2.* || 8.3.* || 8.4.*"
+        "php": "~8.2.0 || ~8.3.0 || ~8.4.0 || ~8.5.0"
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^3",
         "phpstan/phpstan": "^1 || ^2",
-        "phpunit/phpunit": "^10",
+        "phpunit/phpunit": "^11",
         "squizlabs/php_codesniffer": "^3"
     },
     "autoload": {
@@ -39,12 +39,10 @@
     },
     "scripts": {
         "cs:check": [
-            "@putenv PHP_CS_FIXER_IGNORE_ENV=1",
-            "php-cs-fixer fix --dry-run --format=txt --verbose --diff --config=.cs.php --ansi"
+            "php-cs-fixer fix --dry-run --format=txt --verbose --diff --config=.cs.php --ansi --allow-unsupported-php-version=yes"
         ],
         "cs:fix": [
-            "@putenv PHP_CS_FIXER_IGNORE_ENV=1",
-            "php-cs-fixer fix --config=.cs.php --ansi --verbose"
+            "php-cs-fixer fix --config=.cs.php --ansi --verbose --allow-unsupported-php-version=yes"
         ],
         "sniffer:check": "phpcs --standard=phpcs.xml",
         "sniffer:fix": "phpcbf --standard=phpcs.xml",
diff --git a/phpunit.xml b/phpunit.xml
index 2927473..7b7ad74 100644
--- a/phpunit.xml
+++ b/phpunit.xml
@@ -3,7 +3,7 @@
          bootstrap="vendor/autoload.php"
          colors="true"
          backupGlobals="false"
-         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/10.3/phpunit.xsd"
+         xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/11.5/phpunit.xsd"
          cacheDirectory=".phpunit.cache"
          backupStaticProperties="false">
     <coverage/>