diff --git a/cloud/src/Auth/Rbac.php b/cloud/src/Auth/Rbac.php
new file mode 100644
index 0000000..e524c66
--- /dev/null
+++ b/cloud/src/Auth/Rbac.php
@@ -0,0 +1,15 @@
+<?php
+declare(strict_types=1);
+namespace App\Auth;
+
+final class Rbac
+{
+    private const MATRIX = [
+        'admin'    => ['view_events','acknowledge','edit_zones','manage_thresholds','manage_compliance'],
+        'operator' => ['view_events','acknowledge','edit_zones'],
+        'viewer'   => ['view_events'],
+    ];
+    public static function can(string $role, string $permission): bool {
+        return in_array($permission, self::MATRIX[$role] ?? [], true);
+    }
+}
diff --git a/cloud/tests/RbacTest.php b/cloud/tests/RbacTest.php
new file mode 100644
index 0000000..bd7b38f
--- /dev/null
+++ b/cloud/tests/RbacTest.php
@@ -0,0 +1,28 @@
+<?php
+declare(strict_types=1);
+namespace App\Tests;
+use App\Auth\Rbac;
+use PHPUnit\Framework\TestCase;
+
+final class RbacTest extends TestCase
+{
+    public function testViewerCanOnlyView(): void {
+        $this->assertTrue(Rbac::can('viewer', 'view_events'));
+        $this->assertFalse(Rbac::can('viewer', 'acknowledge'));
+        $this->assertFalse(Rbac::can('viewer', 'edit_zones'));
+    }
+    public function testOperator(): void {
+        $this->assertTrue(Rbac::can('operator', 'acknowledge'));
+        $this->assertTrue(Rbac::can('operator', 'edit_zones'));
+        $this->assertFalse(Rbac::can('operator', 'manage_thresholds'));
+    }
+    public function testAdminAll(): void {
+        foreach (['view_events','acknowledge','edit_zones','manage_thresholds','manage_compliance'] as $p) {
+            $this->assertTrue(Rbac::can('admin', $p));
+        }
+    }
+    public function testUnknownDenied(): void {
+        $this->assertFalse(Rbac::can('ghost', 'view_events'));
+        $this->assertFalse(Rbac::can('admin', 'unknown_perm'));
+    }
+}