diff --git a/composer.json b/composer.json
index 04c2cad..48ba4cb 100644
--- a/composer.json
+++ b/composer.json
@@ -76,10 +76,12 @@
             "@composer exec -- php-cs-fixer fix --dry-run --diff"
         ],
         "test": [
+            "@phpstan:smoke",
             "@phpstan",
             "@phpunit"
         ],
         "test:ci": [
+            "@phpstan:smoke",
             "@phpstan:ci",
             "@phpunit"
         ],
@@ -87,6 +89,7 @@
         "phpunit:coverage": "@composer exec -- phpunit --coverage-clover coverage.xml",
         "phpstan": "@composer exec -- phpstan --memory-limit=256M",
         "phpstan:ci": "@composer exec -- phpstan --memory-limit=256M --no-progress --error-format=github",
+        "phpstan:smoke": "@composer exec -- phpstan --memory-limit=256M --no-progress --configuration=tests/smoke/phpstan-smoke.neon.dist",
         "rector": [
             "@composer exec -- rector",
             "@lint"
diff --git a/rules.neon b/rules.neon
index 155872e..94c45c9 100644
--- a/rules.neon
+++ b/rules.neon
@@ -7,6 +7,7 @@ parametersSchema:
             ]))
         ])
         attributeRequirements: structure([
+            excludedClasses: listOf(string())
             attributeDefinitions: listOf(structure([
                 attribute: string()
                 requires: listOf(string())
diff --git a/tests/smoke/fixture.php b/tests/smoke/fixture.php
new file mode 100644
index 0000000..c1fbde9
--- /dev/null
+++ b/tests/smoke/fixture.php
@@ -0,0 +1,13 @@
+<?php declare(strict_types=1);
+
+/**
+ * PHPStan Rules
+ *
+ * @package   PHPStan Rules
+ * @author    IWF Web Solutions <web-solutions@iwf.ch>
+ * @copyright Copyright (c) 2025-2026 IWF Web Solutions <web-solutions@iwf.ch>
+ * @license   https://github.com/iwf-web/phpstan-rules/blob/main/LICENSE.txt MIT License
+ * @link      https://github.com/iwf-web/phpstan-rules
+ */
+// Minimal fixture analysed by the smoke phpstan run. Its only purpose is to
+// trigger PHPStan's schema validation against rules.neon during container boot.
diff --git a/tests/smoke/phpstan-smoke.neon.dist b/tests/smoke/phpstan-smoke.neon.dist
new file mode 100644
index 0000000..9f8b3bc
--- /dev/null
+++ b/tests/smoke/phpstan-smoke.neon.dist
@@ -0,0 +1,7 @@
+includes:
+    - ../../rules.neon
+
+parameters:
+    level: 0
+    paths:
+        - fixture.php