diff --git a/app/Actions/GetAvailableOAuthProviders.php b/app/Actions/GetAvailableOAuthProviders.php
index e7ac14e..bd13c75 100644
--- a/app/Actions/GetAvailableOAuthProviders.php
+++ b/app/Actions/GetAvailableOAuthProviders.php
@@ -6,7 +6,7 @@ namespace App\Actions;
 
 use App\Enums\OAuthProviders;
 
-final class GetAvailableOAuthProviders
+final readonly class GetAvailableOAuthProviders
 {
     /** @return array<int, OAuthProviders> */
     public function handle(): array
diff --git a/app/Actions/GetPathFromUser.php b/app/Actions/GetPathFromUser.php
index a14f8c3..c4cc769 100644
--- a/app/Actions/GetPathFromUser.php
+++ b/app/Actions/GetPathFromUser.php
@@ -6,7 +6,7 @@ namespace App\Actions;
 
 use App\Models\User;
 
-final class GetPathFromUser
+final readonly class GetPathFromUser
 {
     public function handle(): string
     {
diff --git a/app/Actions/GetPathFromVault.php b/app/Actions/GetPathFromVault.php
index 7de943c..af42f2c 100644
--- a/app/Actions/GetPathFromVault.php
+++ b/app/Actions/GetPathFromVault.php
@@ -7,7 +7,7 @@ namespace App\Actions;
 use App\Models\User;
 use App\Models\Vault;
 
-final class GetPathFromVault
+final readonly class GetPathFromVault
 {
     public function handle(Vault $vault): string
     {
diff --git a/app/Actions/GetPathFromVaultNode.php b/app/Actions/GetPathFromVaultNode.php
index d2279dc..3f68b5f 100644
--- a/app/Actions/GetPathFromVaultNode.php
+++ b/app/Actions/GetPathFromVaultNode.php
@@ -8,7 +8,7 @@ use App\Models\User;
 use App\Models\Vault;
 use App\Models\VaultNode;
 
-final class GetPathFromVaultNode
+final readonly class GetPathFromVaultNode
 {
     public function handle(VaultNode $node, bool $includeSelf = true): string
     {
diff --git a/app/Actions/GetUrlFromVaultNode.php b/app/Actions/GetUrlFromVaultNode.php
index 12ff21c..405fc27 100644
--- a/app/Actions/GetUrlFromVaultNode.php
+++ b/app/Actions/GetUrlFromVaultNode.php
@@ -6,7 +6,7 @@ namespace App\Actions;
 
 use App\Models\VaultNode;
 
-final class GetUrlFromVaultNode
+final readonly class GetUrlFromVaultNode
 {
     public function handle(VaultNode $node): string
     {
diff --git a/app/Actions/GetVaultNodeFromPath.php b/app/Actions/GetVaultNodeFromPath.php
index c4ec1bd..7b0337b 100644
--- a/app/Actions/GetVaultNodeFromPath.php
+++ b/app/Actions/GetVaultNodeFromPath.php
@@ -7,7 +7,7 @@ namespace App\Actions;
 use App\Models\VaultNode;
 use Illuminate\Support\Str;
 
-final class GetVaultNodeFromPath
+final readonly class GetVaultNodeFromPath
 {
     public function handle(int $vaultId, string $path, ?int $parentId = null): ?VaultNode
     {
diff --git a/app/Actions/ProcessImportedFile.php b/app/Actions/ProcessImportedFile.php
index 9989242..91e0bbe 100644
--- a/app/Actions/ProcessImportedFile.php
+++ b/app/Actions/ProcessImportedFile.php
@@ -11,7 +11,7 @@ use App\Services\VaultFiles\Note;
 use Illuminate\Http\File;
 use Illuminate\Support\Facades\Storage;
 
-final class ProcessImportedFile
+final readonly class ProcessImportedFile
 {
     public function handle(Vault $vault, VaultNode $parent, string $fileName, string $filePath): void
     {
diff --git a/app/Actions/ProcessImportedVault.php b/app/Actions/ProcessImportedVault.php
index 697580e..387da42 100644
--- a/app/Actions/ProcessImportedVault.php
+++ b/app/Actions/ProcessImportedVault.php
@@ -10,7 +10,7 @@ use App\Services\VaultFiles\Note;
 use Illuminate\Support\Facades\Storage;
 use ZipArchive;
 
-final class ProcessImportedVault
+final readonly class ProcessImportedVault
 {
     public function handle(string $fileName, string $filePath): void
     {
diff --git a/app/Actions/ResolveTwoPaths.php b/app/Actions/ResolveTwoPaths.php
index ce9d508..fc5a3cc 100644
--- a/app/Actions/ResolveTwoPaths.php
+++ b/app/Actions/ResolveTwoPaths.php
@@ -7,7 +7,7 @@ namespace App\Actions;
 use GuzzleHttp\Psr7\UriResolver;
 use GuzzleHttp\Psr7\Utils;
 
-final class ResolveTwoPaths
+final readonly class ResolveTwoPaths
 {
     public function handle(string $currentPath, string $path): string
     {
diff --git a/app/Http/Controllers/Controller.php b/app/Http/Controllers/Controller.php
deleted file mode 100644
index e2af3d2..0000000
--- a/app/Http/Controllers/Controller.php
+++ /dev/null
@@ -1,10 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace App\Http\Controllers;
-
-abstract class Controller
-{
-    //
-}
diff --git a/app/Http/Controllers/FileController.php b/app/Http/Controllers/FileController.php
index dfce130..e4af897 100644
--- a/app/Http/Controllers/FileController.php
+++ b/app/Http/Controllers/FileController.php
@@ -14,7 +14,7 @@ use Illuminate\Support\Facades\Gate;
 use Illuminate\Support\Facades\Storage;
 use Symfony\Component\HttpFoundation\BinaryFileResponse;
 
-final class FileController extends Controller
+final readonly class FileController
 {
     /**
      * Show the file for a given user.
diff --git a/app/Observers/VaultNodeObserver.php b/app/Observers/VaultNodeObserver.php
index f517f70..8bd2725 100644
--- a/app/Observers/VaultNodeObserver.php
+++ b/app/Observers/VaultNodeObserver.php
@@ -8,7 +8,7 @@ use App\Actions\GetPathFromVaultNode;
 use App\Models\VaultNode;
 use Illuminate\Support\Facades\Storage;
 
-final class VaultNodeObserver
+final readonly class VaultNodeObserver
 {
     /**
      * Handle the VaultNode "creating" event.
diff --git a/app/Observers/VaultObserver.php b/app/Observers/VaultObserver.php
index 5b4d92a..147eaa6 100644
--- a/app/Observers/VaultObserver.php
+++ b/app/Observers/VaultObserver.php
@@ -8,7 +8,7 @@ use App\Actions\GetPathFromUser;
 use App\Models\Vault;
 use Illuminate\Support\Facades\Storage;
 
-final class VaultObserver
+final readonly class VaultObserver
 {
     /**
      * Handle the Vault "creating" event.
diff --git a/app/Policies/VaultPolicy.php b/app/Policies/VaultPolicy.php
index ab85e96..2a31531 100644
--- a/app/Policies/VaultPolicy.php
+++ b/app/Policies/VaultPolicy.php
@@ -7,7 +7,7 @@ namespace App\Policies;
 use App\Models\User;
 use App\Models\Vault;
 
-final class VaultPolicy
+final readonly class VaultPolicy
 {
     /**
      * Determine whether the user can view the model.
diff --git a/tests/Unit/ArchTest.php b/tests/Unit/ArchTest.php
index 2223c79..12114a8 100644
--- a/tests/Unit/ArchTest.php
+++ b/tests/Unit/ArchTest.php
@@ -2,6 +2,79 @@
 
 declare(strict_types=1);
 
+use Illuminate\Database\Eloquent\Factories\Factory;
+
 arch()->preset()->php();
 arch()->preset()->laravel();
 arch()->preset()->security();
+
+arch('controllers')
+    ->expect('App\Http\Controllers')
+    ->not->toBeUsed();
+
+arch('avoid mutation')
+    ->expect('App')
+    ->classes()
+    ->toBeReadonly()
+    ->ignoring([
+        'App\Exceptions',
+        'App\Jobs',
+        'App\Livewire',
+        'App\Models',
+        'App\Providers',
+        'App\Services',
+    ]);
+
+arch('avoid inheritance')
+    ->expect('App')
+    ->classes()
+    ->toExtendNothing()
+    ->ignoring([
+        'App\Exceptions',
+        'App\Jobs',
+        'App\Livewire',
+        'App\Models',
+        'App\Providers',
+        'App\Services',
+    ]);
+
+arch('avoid open for extension')
+    ->expect('App')
+    ->classes()
+    ->toBeFinal()
+    ->ignoring([
+        'App\Livewire',
+    ]);
+
+arch('avoid abstraction')
+    ->expect('App')
+    ->not->toBeAbstract();
+
+arch('factories')
+    ->expect('Database\Factories')
+    ->toExtend(Factory::class)
+    ->toHaveMethod('definition')
+    ->toOnlyBeUsedIn([
+        'App\Models',
+    ]);
+
+arch('models')
+    ->expect('App\Models')
+    ->toHaveMethod('casts')
+    ->toOnlyBeUsedIn([
+        'App\Actions',
+        'App\Http',
+        'App\Jobs',
+        'App\Livewire',
+        'App\Models',
+        'App\Observers',
+        'App\Policies',
+        'App\Providers',
+        'App\Services',
+        'Database\Factories',
+        'Database\Seeders',
+    ]);
+
+arch('actions')
+    ->expect('App\Actions')
+    ->toHaveMethod('handle');