diff --git a/.php-cs-fixer.php b/.php-cs-fixer.php
index e575eee..9433c28 100644
--- a/.php-cs-fixer.php
+++ b/.php-cs-fixer.php
@@ -23,7 +23,7 @@
     ->setCacheFile(__DIR__ . '/runtime/cache/.php-cs-fixer.cache')
     ->setParallelConfig(ParallelConfigFactory::detect())
     ->setRules([
-        '@PER-CS2.0' => true,
+        '@PER-CS' => true,
         'no_unused_imports' => true,
     ])
     ->setFinder($finder);
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8dff3b3..ee91ddd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,7 @@
 
 ## 1.2.1 under development
 
+- Chg #430: Replace deprecated PHP CS Fixer rule set `@PER-CS2.0` with `@PER-CS` (@dbuhonov)
 - Chg #447, #450: Allow symfony/console 8 (@samdark)
 - Enh #448: Add grouping to `make` help output (@Xakki, @samdark)
 - Enh #449: Update composer dependencies and refactor to replace use of deprecated classes (@vjik)
diff --git a/config/common/di/error-handler.php b/config/common/di/error-handler.php
index 9155ff7..67a1f53 100644
--- a/config/common/di/error-handler.php
+++ b/config/common/di/error-handler.php
@@ -12,7 +12,7 @@
 return [
     HtmlRenderer::class => [
         '__construct()' => [
-            'traceLink' => static function (string $file, int|null $line) use ($params): string|null {
+            'traceLink' => static function (string $file, ?int $line) use ($params): string|null {
                 if (!isset($params['traceLink'])) {
                     return null;
                 }
diff --git a/src/Environment.php b/src/Environment.php
index fd834d5..62359b7 100644
--- a/src/Environment.php
+++ b/src/Environment.php
@@ -58,7 +58,7 @@ public static function isProd(): bool
     /**
      * @return non-empty-string|null
      */
-    public static function appHostPath(): string|null
+    public static function appHostPath(): ?string
     {
         /** @var non-empty-string|null */
         return self::$values['APP_HOST_PATH'];
@@ -114,7 +114,7 @@ private static function setString(string $key, string $default): void
         self::$values[$key] = $value ?? $default;
     }
 
-    private static function setNonEmptyStringOrNull(string $key, string|null $default): void
+    private static function setNonEmptyStringOrNull(string $key, ?string $default): void
     {
         $value = self::getRawValue($key);
         self::$values[$key] = $value === null || $value === '' ? $default : $value;