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 e1552ac..f97b58c 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@ A PSR-15 middleware to secure your site with SameSite cookies :cookie:
 
 ## Requirements
 
-* PHP 8.1 - 8.4
+* PHP 8.2 - 8.5
 
 ## Installation
 
diff --git a/composer.json b/composer.json
index 4cb5279..aa75e93 100644
--- a/composer.json
+++ b/composer.json
@@ -11,18 +11,18 @@
     ],
     "homepage": "https://github.com/selective-php/samesite-cookie",
     "require": {
-        "php": "8.1.* || 8.2.* || 8.3.* || 8.4.*",
-        "psr/http-message": "^1",
+        "php": "~8.2.0 || ~8.3.0 || ~8.4.0 || ~8.5.0",
+        "psr/http-message": "^2",
         "psr/http-server-handler": "^1",
         "psr/http-server-middleware": "^1"
     },
     "require-dev": {
         "friendsofphp/php-cs-fixer": "^3",
-        "middlewares/utils": "^3 || ^4",
-        "phpstan/phpstan": "^1 || ^2",
-        "phpunit/phpunit": "^10",
+        "middlewares/utils": "^4",
+        "phpstan/phpstan": "^2",
+        "phpunit/phpunit": "^11",
         "slim/psr7": "^1",
-        "squizlabs/php_codesniffer": "^3"
+        "squizlabs/php_codesniffer": "^4"
     },
     "autoload": {
         "psr-4": {
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/>