diff --git a/composer.json b/composer.json
index 5027228..a70c535 100644
--- a/composer.json
+++ b/composer.json
@@ -31,6 +31,11 @@
         "symplify/easy-coding-standard": "^10.0.6",
         "nikic/php-parser": "^4.0"
     },
+    "autoload": {
+        "psr-4": {
+            "JumpTwentyFour\\PhpCodingStandards\\": "src"
+        }
+    },
     "prefer-stable": true,
     "minimum-stability": "dev",
     "config": {
diff --git a/ecs.php b/ecs.php
index 9eefda8..05d6ee7 100644
--- a/ecs.php
+++ b/ecs.php
@@ -2,6 +2,7 @@
 
 declare(strict_types=1);
 
+use JumpTwentyFour\PhpCodingStandards\Sniffs\FinalControllerSniff;
 use PHP_CodeSniffer\Standards\Generic\Sniffs\CodeAnalysis\UnusedFunctionParameterSniff;
 use PHP_CodeSniffer\Standards\Generic\Sniffs\Formatting\SpaceAfterCastSniff;
 use PHP_CodeSniffer\Standards\Generic\Sniffs\Formatting\SpaceAfterNotSniff;
@@ -152,5 +153,6 @@
     $services->set(MethodSpacingSniff::class);
     $services->set(BackedEnumTypeSpacingSniff::class);
     $services->set(UnusedFunctionParameterSniff::class);
+    $services->set(FinalControllerSniff::class);
     $services->set(ValidVariableNameSniff::class);
 };
diff --git a/src/Sniffs/FinalControllerSniff.php b/src/Sniffs/FinalControllerSniff.php
new file mode 100644
index 0000000..395e6e5
--- /dev/null
+++ b/src/Sniffs/FinalControllerSniff.php
@@ -0,0 +1,60 @@
+<?php
+
+declare(strict_types=1);
+
+namespace JumpTwentyFour\PhpCodingStandards\Sniffs;
+
+use PHP_CodeSniffer\Files\File;
+use PHP_CodeSniffer\Sniffs\Sniff;
+use SlevomatCodingStandard\Helpers\TokenHelper;
+
+class FinalControllerSniff implements Sniff
+{
+    public const CONTROLLER_NOT_FINAL = 'ControllerNotFinal';
+
+    public function register(): array
+    {
+        return [
+            T_CLASS,
+        ];
+    }
+
+    public function process(File $phpcsFile, $classPointer): void
+    {
+        $previousPointer = TokenHelper::findPreviousEffective($phpcsFile, $classPointer - 1);
+
+        $tokens = $phpcsFile->getTokens();
+
+        $className = $phpcsFile->getDeclarationName($classPointer);
+
+        if ($className === 'Controller') {
+            return;
+        }
+
+        if (str_contains($className, 'Test')) {
+            return;
+        }
+
+        if (str_contains($className, 'Controller') === false) {
+            return;
+        }
+
+        if ($tokens[$previousPointer]['code'] === T_FINAL) {
+            return;
+        }
+
+        $fix = $phpcsFile->addFixableError(
+            'All controllers should be declared using "final" keyword.',
+            $classPointer - 1,
+            self::CONTROLLER_NOT_FINAL
+        );
+
+        if ($fix === false) {
+            return;
+        }
+
+        $phpcsFile->fixer->beginChangeset();
+        $phpcsFile->fixer->addContent($classPointer - 1, 'final ');
+        $phpcsFile->fixer->endChangeset();
+    }
+}