diff --git a/src/Authentication/Passwords/BaseValidator.php b/src/Authentication/Passwords/BaseValidator.php
index b08a5e879..e6ad30cd6 100644
--- a/src/Authentication/Passwords/BaseValidator.php
+++ b/src/Authentication/Passwords/BaseValidator.php
@@ -15,7 +15,7 @@
 
 use CodeIgniter\Shield\Config\Auth as AuthConfig;
 
-class BaseValidator
+abstract class BaseValidator
 {
     protected ?string $error      = null;
     protected ?string $suggestion = null;
diff --git a/src/Config/BaseAuthToken.php b/src/Config/BaseAuthToken.php
index be8dcdfe9..3eb7b2920 100644
--- a/src/Config/BaseAuthToken.php
+++ b/src/Config/BaseAuthToken.php
@@ -15,7 +15,7 @@
 
 use CodeIgniter\Config\BaseConfig;
 
-class BaseAuthToken extends BaseConfig
+abstract class BaseAuthToken extends BaseConfig
 {
     /**
      * List of HMAC Encryption Keys
diff --git a/structarmed.php b/structarmed.php
index 6cbe357fa..7b67b8809 100644
--- a/structarmed.php
+++ b/structarmed.php
@@ -5,6 +5,7 @@
 use Boundwize\StructArmed\Architecture;
 use Boundwize\StructArmed\Preset\Preset;
 use Boundwize\StructArmed\Preset\Presets\Psr4Preset;
+use Boundwize\StructArmed\Rule\Rules\Class_\ExtendedClassMustBeAbstractOrInstantiatedRule;
 use Boundwize\StructArmed\Rule\Rules\Class_\MustBeFinalRule;
 
 return Architecture::define()
@@ -19,6 +20,9 @@
     ])
     ->cacheDirectory(is_dir('/tmp') ? '/tmp/structarmed' : null)
     ->withPresets(Preset::PSR4(), Preset::CODEQUALITY())
+
+    ->rule('base_classes.must_be_abstract', new ExtendedClassMustBeAbstractOrInstantiatedRule('Source', '/^CodeIgniter\\\\Shield\\\\.*Base.*$/'))
+
     ->layer('tests', __DIR__ . '/tests')
     ->layerPattern('Model', '/^CodeIgniter\\\\Shield\\\\.*Model$/')
     ->layerPattern('Controller', '/^CodeIgniter\\\\Shield\\\\Controllers\\\\.*$/')