diff --git a/ai/backend_prompt_template.md b/ai/backend_prompt_template.md
index c8d0edf..c16ef26 100644
--- a/ai/backend_prompt_template.md
+++ b/ai/backend_prompt_template.md
@@ -20,6 +20,9 @@ Code patterns to follow:
 - Entities: constructor with properties, getters
 - DTOs: simple data containers for creation
 - Repositories: interfaces that define data access
+  - Do not write unit tests for concrete repository implementations
+    (e.g., Doctrine/persistence-backed). They are exercised by e2e
+    tests. Use cases are tested with fake repositories.
 - Use cases: business logic with Request objects
   - When throwing exceptions, add @throws docblock
 - Fakes: in-memory implementations for testing
diff --git a/tests/Unit/Auth/FakeSessionRepositoryTest.php b/tests/Unit/Auth/FakeSessionRepositoryTest.php
deleted file mode 100644
index 6e2bce4..0000000
--- a/tests/Unit/Auth/FakeSessionRepositoryTest.php
+++ /dev/null
@@ -1,68 +0,0 @@
-<?php
-
-namespace Tests\Unit\Auth;
-
-use App\Auth\CreateSessionDto;
-use App\Auth\Session;
-use DateTimeImmutable;
-use PHPUnit\Framework\TestCase;
-use Tests\Fakes\FakeSessionRepository;
-
-class FakeSessionRepositoryTest extends TestCase
-{
-    private FakeSessionRepository $sessionRepo;
-
-    public function setUp(): void
-    {
-        $this->sessionRepo = new FakeSessionRepository();
-    }
-
-    public function test_create_and_find_by_token(): void
-    {
-        $this->sessionRepo->create(new CreateSessionDto(
-            token: 'abc123',
-            userId: 0,
-            createdAt: new DateTimeImmutable('2025-01-01'),
-            expiresAt: new DateTimeImmutable('2025-01-08'),
-        ));
-
-        $session = $this->sessionRepo->findByToken('abc123');
-
-        $this->assertInstanceOf(Session::class, $session);
-        $this->assertEquals('abc123', $session->getToken());
-        $this->assertEquals(0, $session->getUserId());
-    }
-
-    public function test_find_by_token_returns_null_when_missing(): void
-    {
-        $this->assertNull($this->sessionRepo->findByToken('nope'));
-    }
-
-    public function test_find_by_token_returns_fresh_instance(): void
-    {
-        $created = $this->sessionRepo->create(new CreateSessionDto(
-            token: 'abc123',
-            userId: 0,
-            createdAt: new DateTimeImmutable('2025-01-01'),
-            expiresAt: new DateTimeImmutable('2025-01-08'),
-        ));
-
-        $fetched = $this->sessionRepo->findByToken('abc123');
-
-        $this->assertNotSame($created, $fetched);
-    }
-
-    public function test_delete_by_token(): void
-    {
-        $this->sessionRepo->create(new CreateSessionDto(
-            token: 'abc123',
-            userId: 0,
-            createdAt: new DateTimeImmutable('2025-01-01'),
-            expiresAt: new DateTimeImmutable('2025-01-08'),
-        ));
-
-        $this->sessionRepo->deleteByToken('abc123');
-
-        $this->assertNull($this->sessionRepo->findByToken('abc123'));
-    }
-}
diff --git a/tests/Unit/User/FakeUserRepositoryTest.php b/tests/Unit/User/FakeUserRepositoryTest.php
deleted file mode 100644
index 4df07f0..0000000
--- a/tests/Unit/User/FakeUserRepositoryTest.php
+++ /dev/null
@@ -1,52 +0,0 @@
-<?php
-
-namespace Tests\Unit\User;
-
-use App\User\UseCases\CreateUserDto;
-use App\User\User;
-use App\ValueObjects\EmailAddress;
-use PHPUnit\Framework\TestCase;
-use Tests\Fakes\FakeUserRepository;
-
-class FakeUserRepositoryTest extends TestCase
-{
-    public function test_find_by_email_returns_user(): void
-    {
-        $userRepo = new FakeUserRepository();
-        $userRepo->create(new CreateUserDto(
-            email: new EmailAddress('test@test.com'),
-            passwordHash: '',
-        ));
-
-        $user = $userRepo->findByEmail(new EmailAddress('test@test.com'));
-
-        $this->assertInstanceOf(User::class, $user);
-        $this->assertEquals('test@test.com', $user->getEmail()->value());
-    }
-
-    public function test_find_by_email_returns_null_when_not_found(): void
-    {
-        $userRepo = new FakeUserRepository();
-
-        $user = $userRepo->findByEmail(
-            new EmailAddress('missing@test.com')
-        );
-
-        $this->assertNull($user);
-    }
-
-    public function test_find_by_email_returns_fresh_instance(): void
-    {
-        $userRepo = new FakeUserRepository();
-        $created = $userRepo->create(new CreateUserDto(
-            email: new EmailAddress('test@test.com'),
-            passwordHash: '',
-        ));
-
-        $fetched = $userRepo->findByEmail(
-            new EmailAddress('test@test.com')
-        );
-
-        $this->assertNotSame($created, $fetched);
-    }
-}