diff --git a/tests/Service/Auth/AuthExternalIdentityGatewayTest.php b/tests/Service/Auth/AuthExternalIdentityGatewayTest.php
new file mode 100644
index 0000000..7a449ea
--- /dev/null
+++ b/tests/Service/Auth/AuthExternalIdentityGatewayTest.php
@@ -0,0 +1,64 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Auth;
+
+use MintyPHP\Repository\User\UserExternalIdentityRepositoryInterface;
+use MintyPHP\Service\Auth\AuthExternalIdentityGateway;
+use PHPUnit\Framework\TestCase;
+
+class AuthExternalIdentityGatewayTest extends TestCase
+{
+    public function testFindByProviderTidOidDelegatesToRepository(): void
+    {
+        $row = ['id' => 1, 'user_id' => 42, 'provider' => 'microsoft', 'tid' => 'tenant-abc', 'oid' => 'oid-xyz'];
+
+        $repo = $this->createMock(UserExternalIdentityRepositoryInterface::class);
+        $repo->expects($this->once())
+            ->method('findByProviderTidOid')
+            ->with('microsoft', 'tenant-abc', 'oid-xyz')
+            ->willReturn($row);
+
+        $gateway = new AuthExternalIdentityGateway($repo);
+        $this->assertSame($row, $gateway->findByProviderTidOid('microsoft', 'tenant-abc', 'oid-xyz'));
+    }
+
+    public function testFindByProviderTidOidReturnsNullWhenNotFound(): void
+    {
+        $repo = $this->createMock(UserExternalIdentityRepositoryInterface::class);
+        $repo->expects($this->once())
+            ->method('findByProviderTidOid')
+            ->with('microsoft', 'unknown-tid', 'unknown-oid')
+            ->willReturn(null);
+
+        $gateway = new AuthExternalIdentityGateway($repo);
+        $this->assertNull($gateway->findByProviderTidOid('microsoft', 'unknown-tid', 'unknown-oid'));
+    }
+
+    public function testFindByProviderIssuerSubjectDelegatesToRepository(): void
+    {
+        $row = ['id' => 2, 'user_id' => 99, 'provider' => 'oidc', 'issuer' => 'https://issuer.example', 'subject' => 'sub-123'];
+
+        $repo = $this->createMock(UserExternalIdentityRepositoryInterface::class);
+        $repo->expects($this->once())
+            ->method('findByProviderIssuerSubject')
+            ->with('oidc', 'https://issuer.example', 'sub-123')
+            ->willReturn($row);
+
+        $gateway = new AuthExternalIdentityGateway($repo);
+        $this->assertSame($row, $gateway->findByProviderIssuerSubject('oidc', 'https://issuer.example', 'sub-123'));
+    }
+
+    public function testCreateLinkReturnsBool(): void
+    {
+        $data = ['user_id' => 42, 'provider' => 'microsoft', 'tid' => 'tenant-abc', 'oid' => 'oid-xyz'];
+
+        $repo = $this->createMock(UserExternalIdentityRepositoryInterface::class);
+        $repo->expects($this->once())
+            ->method('createLink')
+            ->with($data)
+            ->willReturn(7);
+
+        $gateway = new AuthExternalIdentityGateway($repo);
+        $this->assertTrue($gateway->createLink($data));
+    }
+}
diff --git a/tests/Service/Auth/AuthTenantGatewayTest.php b/tests/Service/Auth/AuthTenantGatewayTest.php
new file mode 100644
index 0000000..4e28df5
--- /dev/null
+++ b/tests/Service/Auth/AuthTenantGatewayTest.php
@@ -0,0 +1,66 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Auth;
+
+use MintyPHP\Repository\Tenant\TenantRepositoryInterface;
+use MintyPHP\Service\Auth\AuthTenantGateway;
+use PHPUnit\Framework\TestCase;
+
+class AuthTenantGatewayTest extends TestCase
+{
+    public function testFindByIdDelegatesToRepository(): void
+    {
+        $tenant = ['id' => 1, 'name' => 'Acme Corp', 'uuid' => 'abc-123'];
+
+        $repo = $this->createMock(TenantRepositoryInterface::class);
+        $repo->expects($this->once())
+            ->method('find')
+            ->with(1)
+            ->willReturn($tenant);
+
+        $gateway = new AuthTenantGateway($repo);
+        $this->assertSame($tenant, $gateway->findById(1));
+    }
+
+    public function testFindByIdReturnsNullWhenNotFound(): void
+    {
+        $repo = $this->createMock(TenantRepositoryInterface::class);
+        $repo->expects($this->once())
+            ->method('find')
+            ->with(999)
+            ->willReturn(null);
+
+        $gateway = new AuthTenantGateway($repo);
+        $this->assertNull($gateway->findById(999));
+    }
+
+    public function testFindByUuidDelegatesToRepository(): void
+    {
+        $tenant = ['id' => 5, 'name' => 'Beta Inc', 'uuid' => 'def-456'];
+
+        $repo = $this->createMock(TenantRepositoryInterface::class);
+        $repo->expects($this->once())
+            ->method('findByUuid')
+            ->with('def-456')
+            ->willReturn($tenant);
+
+        $gateway = new AuthTenantGateway($repo);
+        $this->assertSame($tenant, $gateway->findByUuid('def-456'));
+    }
+
+    public function testListDelegatesToRepository(): void
+    {
+        $tenants = [
+            ['id' => 1, 'name' => 'Acme Corp'],
+            ['id' => 2, 'name' => 'Beta Inc'],
+        ];
+
+        $repo = $this->createMock(TenantRepositoryInterface::class);
+        $repo->expects($this->once())
+            ->method('list')
+            ->willReturn($tenants);
+
+        $gateway = new AuthTenantGateway($repo);
+        $this->assertSame($tenants, $gateway->list());
+    }
+}
diff --git a/tests/Service/Directory/DirectorySettingsGatewayTest.php b/tests/Service/Directory/DirectorySettingsGatewayTest.php
new file mode 100644
index 0000000..6c77e3c
--- /dev/null
+++ b/tests/Service/Directory/DirectorySettingsGatewayTest.php
@@ -0,0 +1,115 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Directory;
+
+use MintyPHP\Service\Directory\DirectorySettingsGateway;
+use MintyPHP\Service\Settings\SettingsAppGateway;
+use MintyPHP\Service\Settings\SettingsDefaultsGateway;
+use PHPUnit\Framework\TestCase;
+
+class DirectorySettingsGatewayTest extends TestCase
+{
+    public function testSetDefaultTenantIdDelegatesToSettingsDefaultsGateway(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->expects($this->once())
+            ->method('setDefaultTenantId')
+            ->with(42);
+
+        $app = $this->createMock(SettingsAppGateway::class);
+
+        $gateway = new DirectorySettingsGateway($defaults, $app);
+        $gateway->setDefaultTenantId(42);
+    }
+
+    public function testSetDefaultTenantIdAcceptsNull(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->expects($this->once())
+            ->method('setDefaultTenantId')
+            ->with(null);
+
+        $app = $this->createMock(SettingsAppGateway::class);
+
+        $gateway = new DirectorySettingsGateway($defaults, $app);
+        $gateway->setDefaultTenantId(null);
+    }
+
+    public function testSetDefaultDepartmentIdDelegatesToSettingsDefaultsGateway(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->expects($this->once())
+            ->method('setDefaultDepartmentId')
+            ->with(7);
+
+        $app = $this->createMock(SettingsAppGateway::class);
+
+        $gateway = new DirectorySettingsGateway($defaults, $app);
+        $gateway->setDefaultDepartmentId(7);
+    }
+
+    public function testSetDefaultDepartmentIdAcceptsNull(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->expects($this->once())
+            ->method('setDefaultDepartmentId')
+            ->with(null);
+
+        $app = $this->createMock(SettingsAppGateway::class);
+
+        $gateway = new DirectorySettingsGateway($defaults, $app);
+        $gateway->setDefaultDepartmentId(null);
+    }
+
+    public function testSetDefaultRoleIdDelegatesToSettingsDefaultsGateway(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->expects($this->once())
+            ->method('setDefaultRoleId')
+            ->with(3);
+
+        $app = $this->createMock(SettingsAppGateway::class);
+
+        $gateway = new DirectorySettingsGateway($defaults, $app);
+        $gateway->setDefaultRoleId(3);
+    }
+
+    public function testSetDefaultRoleIdAcceptsNull(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->expects($this->once())
+            ->method('setDefaultRoleId')
+            ->with(null);
+
+        $app = $this->createMock(SettingsAppGateway::class);
+
+        $gateway = new DirectorySettingsGateway($defaults, $app);
+        $gateway->setDefaultRoleId(null);
+    }
+
+    public function testIsAllowedThemeDelegatesToSettingsAppGateway(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $app = $this->createMock(SettingsAppGateway::class);
+        $app->expects($this->once())
+            ->method('isAllowedTheme')
+            ->with('dark')
+            ->willReturn(true);
+
+        $gateway = new DirectorySettingsGateway($defaults, $app);
+        $this->assertTrue($gateway->isAllowedTheme('dark'));
+    }
+
+    public function testIsAllowedThemeReturnsFalseForUnknownTheme(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $app = $this->createMock(SettingsAppGateway::class);
+        $app->expects($this->once())
+            ->method('isAllowedTheme')
+            ->with('neon')
+            ->willReturn(false);
+
+        $gateway = new DirectorySettingsGateway($defaults, $app);
+        $this->assertFalse($gateway->isAllowedTheme('neon'));
+    }
+}
diff --git a/tests/Service/Settings/SettingsAppGatewayTest.php b/tests/Service/Settings/SettingsAppGatewayTest.php
new file mode 100644
index 0000000..bfa4481
--- /dev/null
+++ b/tests/Service/Settings/SettingsAppGatewayTest.php
@@ -0,0 +1,106 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Settings;
+
+use MintyPHP\Repository\Settings\SettingRepositoryInterface;
+use MintyPHP\Service\Settings\SettingsAppGateway;
+use MintyPHP\Service\Settings\SettingsMetadataGateway;
+use MintyPHP\Service\Settings\ThemeConfigGateway;
+use PHPUnit\Framework\TestCase;
+
+class SettingsAppGatewayTest extends TestCase
+{
+    private function createGateway(SettingRepositoryInterface $settings, ?ThemeConfigGateway $themeConfig = null): SettingsAppGateway
+    {
+        $themeConfig ??= $this->createDefaultThemeConfig();
+
+        return new SettingsAppGateway(new SettingsMetadataGateway($settings), $themeConfig);
+    }
+
+    private function createDefaultThemeConfig(): ThemeConfigGateway
+    {
+        $themeConfig = $this->createMock(ThemeConfigGateway::class);
+        $themeConfig->method('all')->willReturn(['light' => 'Light', 'dark' => 'Dark']);
+
+        return $themeConfig;
+    }
+
+    public function testGetAppTitleReturnsNullWhenEmpty(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->any())->method('getValue')->with('app_title')->willReturn(null);
+
+        $gateway = $this->createGateway($settings);
+        $this->assertNull($gateway->getAppTitle());
+    }
+
+    public function testGetAppTitleReturnsTrimmedValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->any())->method('getValue')->with('app_title')->willReturn('  My App  ');
+
+        $gateway = $this->createGateway($settings);
+        $this->assertSame('My App', $gateway->getAppTitle());
+    }
+
+    public function testGetAppLocaleReturnsNullWhenNotSet(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->any())->method('getValue')->with('app_locale')->willReturn(null);
+
+        $gateway = $this->createGateway($settings);
+        $this->assertNull($gateway->getAppLocale());
+    }
+
+    public function testIsRegistrationEnabledDefaultsToTrue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->any())->method('getValue')->with('app_registration')->willReturn(null);
+
+        $gateway = $this->createGateway($settings);
+        $this->assertTrue($gateway->isRegistrationEnabled());
+    }
+
+    public function testIsRegistrationEnabledReturnsFalseWhenDisabled(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->any())->method('getValue')->with('app_registration')->willReturn('0');
+
+        $gateway = $this->createGateway($settings);
+        $this->assertFalse($gateway->isRegistrationEnabled());
+    }
+
+    public function testGetAppPrimaryColorRejectsInvalidFormat(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->any())->method('getValue')->with('app_primary_color')->willReturn('not-a-color');
+
+        $gateway = $this->createGateway($settings);
+        $this->assertNull($gateway->getAppPrimaryColor());
+    }
+
+    public function testGetAppPrimaryColorReturnsValidHex(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->any())->method('getValue')->with('app_primary_color')->willReturn('#ff5500');
+
+        $gateway = $this->createGateway($settings);
+        $this->assertSame('#ff5500', $gateway->getAppPrimaryColor());
+    }
+
+    public function testIsAllowedThemeReturnsTrueForKnownTheme(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+
+        $gateway = $this->createGateway($settings);
+        $this->assertTrue($gateway->isAllowedTheme('dark'));
+    }
+
+    public function testIsAllowedThemeReturnsFalseForUnknownTheme(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+
+        $gateway = $this->createGateway($settings);
+        $this->assertFalse($gateway->isAllowedTheme('neon'));
+    }
+}
diff --git a/tests/Service/Settings/SettingsFrontendTelemetryGatewayTest.php b/tests/Service/Settings/SettingsFrontendTelemetryGatewayTest.php
new file mode 100644
index 0000000..c498dca
--- /dev/null
+++ b/tests/Service/Settings/SettingsFrontendTelemetryGatewayTest.php
@@ -0,0 +1,116 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Settings;
+
+use MintyPHP\Repository\Settings\SettingRepositoryInterface;
+use MintyPHP\Service\Settings\SettingsFrontendTelemetryGateway;
+use MintyPHP\Service\Settings\SettingsMetadataGateway;
+use PHPUnit\Framework\TestCase;
+
+class SettingsFrontendTelemetryGatewayTest extends TestCase
+{
+    public function testIsFrontendTelemetryEnabledReturnsFalseByDefault(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return null;
+        });
+
+        $gateway = new SettingsFrontendTelemetryGateway(new SettingsMetadataGateway($settings));
+        $this->assertFalse($gateway->isFrontendTelemetryEnabled());
+    }
+
+    public function testIsFrontendTelemetryEnabledReturnsTrueWhenEnabled(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'frontend_telemetry_enabled' => '1',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsFrontendTelemetryGateway(new SettingsMetadataGateway($settings));
+        $this->assertTrue($gateway->isFrontendTelemetryEnabled());
+    }
+
+    public function testGetFrontendTelemetrySampleRateDefaultsToPointTwo(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return null;
+        });
+
+        $gateway = new SettingsFrontendTelemetryGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(0.2, $gateway->getFrontendTelemetrySampleRate());
+    }
+
+    public function testGetFrontendTelemetrySampleRateClampsToZero(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'frontend_telemetry_sample_rate' => '-0.5',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsFrontendTelemetryGateway(new SettingsMetadataGateway($settings));
+        // Out-of-range values fall back to the default 0.2
+        $this->assertSame(0.2, $gateway->getFrontendTelemetrySampleRate());
+    }
+
+    public function testGetFrontendTelemetrySampleRateClampsToOne(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'frontend_telemetry_sample_rate' => '1.5',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsFrontendTelemetryGateway(new SettingsMetadataGateway($settings));
+        // Out-of-range values fall back to the default 0.2
+        $this->assertSame(0.2, $gateway->getFrontendTelemetrySampleRate());
+    }
+
+    public function testGetFrontendTelemetryAllowedEventsReturnsDefaults(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return null;
+        });
+
+        $gateway = new SettingsFrontendTelemetryGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(['warn_once', 'ajax_error'], $gateway->getFrontendTelemetryAllowedEvents());
+    }
+
+    public function testSetFrontendTelemetryAllowedEventsNormalizesAndDeduplicates(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $stored = null;
+        $settings->expects($this->once())
+            ->method('set')
+            ->willReturnCallback(static function (string $key, ?string $value) use (&$stored): bool {
+                if ($key === 'frontend_telemetry_allowed_events') {
+                    $stored = $value;
+                }
+                return true;
+            });
+        $settings->method('getValue')->willReturnCallback(static function (string $key) use (&$stored): ?string {
+            return match ($key) {
+                'frontend_telemetry_allowed_events' => $stored,
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsFrontendTelemetryGateway(new SettingsMetadataGateway($settings));
+
+        // Pass duplicates with mixed casing and frontend. prefix
+        $this->assertTrue($gateway->setFrontendTelemetryAllowedEvents('frontend.WARN_ONCE, warn_once, AJAX_ERROR'));
+
+        // Stored value should be sorted, deduplicated, and lowercased
+        $this->assertSame('ajax_error,warn_once', $stored);
+    }
+}
diff --git a/tests/Service/Settings/SettingsLoginPersistenceGatewayTest.php b/tests/Service/Settings/SettingsLoginPersistenceGatewayTest.php
new file mode 100644
index 0000000..ccebd4a
--- /dev/null
+++ b/tests/Service/Settings/SettingsLoginPersistenceGatewayTest.php
@@ -0,0 +1,109 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Settings;
+
+use MintyPHP\Repository\Settings\SettingRepositoryInterface;
+use MintyPHP\Service\Settings\SettingsLoginPersistenceGateway;
+use MintyPHP\Service\Settings\SettingsMetadataGateway;
+use PHPUnit\Framework\TestCase;
+
+class SettingsLoginPersistenceGatewayTest extends TestCase
+{
+    public function testIsMicrosoftAutoRememberDefaultReturnsFalseByDefault(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+
+        $gateway = new SettingsLoginPersistenceGateway(new SettingsMetadataGateway($settings));
+        $this->assertFalse($gateway->isMicrosoftAutoRememberDefault());
+    }
+
+    public function testIsMicrosoftAutoRememberDefaultReturnsTrueWhenEnabled(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'microsoft_auto_remember_default' => '1',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsLoginPersistenceGateway(new SettingsMetadataGateway($settings));
+        $this->assertTrue($gateway->isMicrosoftAutoRememberDefault());
+    }
+
+    public function testGetRememberTokenLifetimeDaysDefaultsTo30(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+
+        $gateway = new SettingsLoginPersistenceGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(30, $gateway->getRememberTokenLifetimeDays());
+    }
+
+    public function testGetRememberTokenLifetimeDaysReturnsValidValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'remember_token_lifetime_days' => '90',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsLoginPersistenceGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(90, $gateway->getRememberTokenLifetimeDays());
+    }
+
+    public function testGetRememberTokenLifetimeDaysClampsToMinimum(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'remember_token_lifetime_days' => '0',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsLoginPersistenceGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(30, $gateway->getRememberTokenLifetimeDays());
+    }
+
+    public function testGetRememberTokenLifetimeDaysClampsToMaximum(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'remember_token_lifetime_days' => '500',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsLoginPersistenceGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(30, $gateway->getRememberTokenLifetimeDays());
+    }
+
+    public function testSetRememberTokenLifetimeDaysRejectsBelowRange(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+        $settings->expects($this->never())->method('set');
+
+        $gateway = new SettingsLoginPersistenceGateway(new SettingsMetadataGateway($settings));
+        $this->assertFalse($gateway->setRememberTokenLifetimeDays(0));
+    }
+
+    public function testGetRememberTokenLifetimeSecondsConvertsDays(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'remember_token_lifetime_days' => '7',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsLoginPersistenceGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(604800, $gateway->getRememberTokenLifetimeSeconds());
+    }
+}
diff --git a/tests/Service/Settings/SettingsMetadataGatewayTest.php b/tests/Service/Settings/SettingsMetadataGatewayTest.php
new file mode 100644
index 0000000..a1035c5
--- /dev/null
+++ b/tests/Service/Settings/SettingsMetadataGatewayTest.php
@@ -0,0 +1,71 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Settings;
+
+use MintyPHP\Repository\Settings\SettingRepositoryInterface;
+use MintyPHP\Service\Settings\SettingsMetadataGateway;
+use PHPUnit\Framework\TestCase;
+
+class SettingsMetadataGatewayTest extends TestCase
+{
+    public function testGetValueDelegatesToRepository(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->once())
+            ->method('getValue')
+            ->with('some_key')
+            ->willReturn('some_value');
+
+        $gateway = new SettingsMetadataGateway($settings);
+        $this->assertSame('some_value', $gateway->getValue('some_key'));
+    }
+
+    public function testGetIntReturnsIntegerValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'numeric_key' => '42',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsMetadataGateway($settings);
+        $this->assertSame(42, $gateway->getInt('numeric_key'));
+    }
+
+    public function testGetIntReturnsNullForEmptyValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'empty_key' => '',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsMetadataGateway($settings);
+        $this->assertNull($gateway->getInt('empty_key'));
+    }
+
+    public function testGetIntReturnsNullWhenNoSetting(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+
+        $gateway = new SettingsMetadataGateway($settings);
+        $this->assertNull($gateway->getInt('missing_key'));
+    }
+
+    public function testSetDelegatesToRepository(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->once())
+            ->method('set')
+            ->with('my_key', 'my_value', 'description text')
+            ->willReturn(true);
+
+        $gateway = new SettingsMetadataGateway($settings);
+        $this->assertTrue($gateway->set('my_key', 'my_value', 'description text'));
+    }
+}
diff --git a/tests/Service/Settings/SettingsSessionGatewayTest.php b/tests/Service/Settings/SettingsSessionGatewayTest.php
new file mode 100644
index 0000000..97d7852
--- /dev/null
+++ b/tests/Service/Settings/SettingsSessionGatewayTest.php
@@ -0,0 +1,123 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Settings;
+
+use MintyPHP\Repository\Settings\SettingRepositoryInterface;
+use MintyPHP\Service\Settings\SettingsMetadataGateway;
+use MintyPHP\Service\Settings\SettingsSessionGateway;
+use PHPUnit\Framework\TestCase;
+
+class SettingsSessionGatewayTest extends TestCase
+{
+    public function testGetSessionIdleTimeoutMinutesDefaultsTo30WhenNoSetting(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(30, $gateway->getSessionIdleTimeoutMinutes());
+    }
+
+    public function testGetSessionIdleTimeoutMinutesReturnsValueWithinRange(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'session_idle_timeout_minutes' => '60',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(60, $gateway->getSessionIdleTimeoutMinutes());
+    }
+
+    public function testGetSessionIdleTimeoutMinutesClampsToMinimum(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'session_idle_timeout_minutes' => '3',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(30, $gateway->getSessionIdleTimeoutMinutes());
+    }
+
+    public function testGetSessionIdleTimeoutMinutesClampsToMaximum(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'session_idle_timeout_minutes' => '2000',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(30, $gateway->getSessionIdleTimeoutMinutes());
+    }
+
+    public function testSetSessionIdleTimeoutMinutesRejectsBelowRange(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+        $settings->expects($this->never())->method('set');
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertFalse($gateway->setSessionIdleTimeoutMinutes(3));
+    }
+
+    public function testGetSessionAbsoluteTimeoutHoursDefaultsTo8(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(8, $gateway->getSessionAbsoluteTimeoutHours());
+    }
+
+    public function testGetSessionAbsoluteTimeoutHoursReturnsValidValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'session_absolute_timeout_hours' => '12',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(12, $gateway->getSessionAbsoluteTimeoutHours());
+    }
+
+    public function testGetSessionIdleTimeoutSecondsConvertsMinutes(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'session_idle_timeout_minutes' => '60',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(3600, $gateway->getSessionIdleTimeoutSeconds());
+    }
+
+    public function testGetSessionAbsoluteTimeoutSecondsConvertsHours(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'session_absolute_timeout_hours' => '12',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSessionGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(43200, $gateway->getSessionAbsoluteTimeoutSeconds());
+    }
+}
diff --git a/tests/Service/Settings/SettingsSmtpGatewayTest.php b/tests/Service/Settings/SettingsSmtpGatewayTest.php
new file mode 100644
index 0000000..335d9ff
--- /dev/null
+++ b/tests/Service/Settings/SettingsSmtpGatewayTest.php
@@ -0,0 +1,143 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Settings;
+
+use MintyPHP\Repository\Settings\SettingRepositoryInterface;
+use MintyPHP\Service\Settings\SettingsMetadataGateway;
+use MintyPHP\Service\Settings\SettingsSmtpGateway;
+use PHPUnit\Framework\TestCase;
+
+class SettingsSmtpGatewayTest extends TestCase
+{
+    public function testGetSmtpHostReturnsNullWhenEmpty(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return null;
+        });
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertNull($gateway->getSmtpHost());
+    }
+
+    public function testGetSmtpHostReturnsTrimedValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'smtp_host' => '  mail.example.com  ',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame('mail.example.com', $gateway->getSmtpHost());
+    }
+
+    public function testGetSmtpPortReturnsNullWhenEmpty(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'smtp_port' => '',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertNull($gateway->getSmtpPort());
+    }
+
+    public function testGetSmtpPortReturnsValidPort(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'smtp_port' => '587',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(587, $gateway->getSmtpPort());
+    }
+
+    public function testGetSmtpPortReturnsNullForZero(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'smtp_port' => '0',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertNull($gateway->getSmtpPort());
+    }
+
+    public function testGetSmtpSecureReturnsNullForNone(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'smtp_secure' => 'none',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertNull($gateway->getSmtpSecure());
+    }
+
+    public function testGetSmtpSecureReturnsTls(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'smtp_secure' => '  TLS  ',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame('tls', $gateway->getSmtpSecure());
+    }
+
+    public function testGetSmtpSecureReturnsNullForInvalidValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'smtp_secure' => 'starttls',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertNull($gateway->getSmtpSecure());
+    }
+
+    public function testSetSmtpPortRejectsNegativePort(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+        $settings->expects($this->once())
+            ->method('set')
+            ->with('smtp_port', null, 'setting.smtp_port')
+            ->willReturn(true);
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        // Negative port is treated as invalid; set stores null (clears the setting)
+        $this->assertTrue($gateway->setSmtpPort(-1));
+    }
+
+    public function testSetSmtpSecureRejectsInvalidValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->expects($this->never())->method('set');
+
+        $gateway = new SettingsSmtpGateway(new SettingsMetadataGateway($settings));
+        $this->assertFalse($gateway->setSmtpSecure('starttls'));
+    }
+}
diff --git a/tests/Service/Settings/SettingsSystemAuditGatewayTest.php b/tests/Service/Settings/SettingsSystemAuditGatewayTest.php
new file mode 100644
index 0000000..fde222c
--- /dev/null
+++ b/tests/Service/Settings/SettingsSystemAuditGatewayTest.php
@@ -0,0 +1,95 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Settings;
+
+use MintyPHP\Repository\Settings\SettingRepositoryInterface;
+use MintyPHP\Service\Settings\SettingsMetadataGateway;
+use MintyPHP\Service\Settings\SettingsSystemAuditGateway;
+use PHPUnit\Framework\TestCase;
+
+class SettingsSystemAuditGatewayTest extends TestCase
+{
+    public function testIsSystemAuditEnabledReturnsTrueByDefault(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+
+        $gateway = new SettingsSystemAuditGateway(new SettingsMetadataGateway($settings));
+        $this->assertTrue($gateway->isSystemAuditEnabled());
+    }
+
+    public function testIsSystemAuditEnabledReturnsFalseWhenDisabled(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'system_audit_enabled' => '0',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSystemAuditGateway(new SettingsMetadataGateway($settings));
+        $this->assertFalse($gateway->isSystemAuditEnabled());
+    }
+
+    public function testGetSystemAuditRetentionDaysDefaultsTo365(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+
+        $gateway = new SettingsSystemAuditGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(365, $gateway->getSystemAuditRetentionDays());
+    }
+
+    public function testGetSystemAuditRetentionDaysReturnsValidValue(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'system_audit_retention_days' => '180',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSystemAuditGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(180, $gateway->getSystemAuditRetentionDays());
+    }
+
+    public function testGetSystemAuditRetentionDaysClampsToMinimum(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'system_audit_retention_days' => '10',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSystemAuditGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(365, $gateway->getSystemAuditRetentionDays());
+    }
+
+    public function testGetSystemAuditRetentionDaysClampsToMaximum(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturnCallback(static function (string $key): ?string {
+            return match ($key) {
+                'system_audit_retention_days' => '2000',
+                default => null,
+            };
+        });
+
+        $gateway = new SettingsSystemAuditGateway(new SettingsMetadataGateway($settings));
+        $this->assertSame(365, $gateway->getSystemAuditRetentionDays());
+    }
+
+    public function testSetSystemAuditRetentionDaysRejectsBelowRange(): void
+    {
+        $settings = $this->createMock(SettingRepositoryInterface::class);
+        $settings->method('getValue')->willReturn(null);
+        $settings->expects($this->never())->method('set');
+
+        $gateway = new SettingsSystemAuditGateway(new SettingsMetadataGateway($settings));
+        $this->assertFalse($gateway->setSystemAuditRetentionDays(10));
+    }
+}
diff --git a/tests/Service/Ui/HotkeyServiceTest.php b/tests/Service/Ui/HotkeyServiceTest.php
new file mode 100644
index 0000000..da66b8c
--- /dev/null
+++ b/tests/Service/Ui/HotkeyServiceTest.php
@@ -0,0 +1,83 @@
+<?php
+
+namespace MintyPHP\Tests\Service\Ui;
+
+use MintyPHP\Service\Ui\HotkeyService;
+use PHPUnit\Framework\TestCase;
+
+class HotkeyServiceTest extends TestCase
+{
+    public function testListReturnsNonEmptyArray(): void
+    {
+        $result = HotkeyService::list();
+
+        $this->assertIsArray($result);
+        $this->assertNotEmpty($result);
+    }
+
+    public function testListEntriesHaveRequiredKeys(): void
+    {
+        $result = HotkeyService::list();
+
+        foreach ($result as $index => $entry) {
+            $this->assertArrayHasKey('action_key', $entry, "Entry #{$index} is missing 'action_key'");
+            $this->assertArrayHasKey('mac', $entry, "Entry #{$index} is missing 'mac'");
+            $this->assertArrayHasKey('win', $entry, "Entry #{$index} is missing 'win'");
+            $this->assertNotEmpty($entry['action_key'], "Entry #{$index} has empty 'action_key'");
+            $this->assertNotEmpty($entry['mac'], "Entry #{$index} has empty 'mac'");
+            $this->assertNotEmpty($entry['win'], "Entry #{$index} has empty 'win'");
+        }
+    }
+
+    public function testListEntriesHaveExactlyThreeKeys(): void
+    {
+        $result = HotkeyService::list();
+
+        foreach ($result as $index => $entry) {
+            $this->assertCount(3, $entry, "Entry #{$index} should have exactly 3 keys");
+        }
+    }
+
+    public function testSearchKeywordsReturnsNonEmptyArray(): void
+    {
+        $result = HotkeyService::searchKeywords();
+
+        $this->assertIsArray($result);
+        $this->assertNotEmpty($result);
+    }
+
+    public function testSearchKeywordsContainsExpectedTerms(): void
+    {
+        $result = HotkeyService::searchKeywords();
+
+        $this->assertContains('hotkey', $result);
+        $this->assertContains('shortcut', $result);
+        $this->assertContains('keyboard', $result);
+    }
+
+    public function testSearchKeywordsAreAllStrings(): void
+    {
+        $result = HotkeyService::searchKeywords();
+
+        foreach ($result as $keyword) {
+            $this->assertIsString($keyword);
+            $this->assertNotEmpty($keyword);
+        }
+    }
+
+    public function testListReturnsDeterministicResult(): void
+    {
+        $first = HotkeyService::list();
+        $second = HotkeyService::list();
+
+        $this->assertSame($first, $second);
+    }
+
+    public function testSearchKeywordsReturnsDeterministicResult(): void
+    {
+        $first = HotkeyService::searchKeywords();
+        $second = HotkeyService::searchKeywords();
+
+        $this->assertSame($first, $second);
+    }
+}
diff --git a/tests/Service/User/UserSettingsGatewayTest.php b/tests/Service/User/UserSettingsGatewayTest.php
new file mode 100644
index 0000000..8d66c81
--- /dev/null
+++ b/tests/Service/User/UserSettingsGatewayTest.php
@@ -0,0 +1,130 @@
+<?php
+
+namespace MintyPHP\Tests\Service\User;
+
+use MintyPHP\Service\Settings\SettingsAppGateway;
+use MintyPHP\Service\Settings\SettingsDefaultsGateway;
+use MintyPHP\Service\Settings\SettingsUserLifecycleGateway;
+use MintyPHP\Service\User\UserSettingsGateway;
+use PHPUnit\Framework\TestCase;
+
+class UserSettingsGatewayTest extends TestCase
+{
+    public function testGetDefaultTenantIdDelegates(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->method('getDefaultTenantId')->willReturn(5);
+
+        $gateway = new UserSettingsGateway($defaults, $this->createMock(SettingsAppGateway::class), $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertSame(5, $gateway->getDefaultTenantId());
+    }
+
+    public function testGetDefaultTenantIdReturnsNullWhenUnset(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->method('getDefaultTenantId')->willReturn(null);
+
+        $gateway = new UserSettingsGateway($defaults, $this->createMock(SettingsAppGateway::class), $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertNull($gateway->getDefaultTenantId());
+    }
+
+    public function testGetDefaultRoleIdDelegates(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->method('getDefaultRoleId')->willReturn(12);
+
+        $gateway = new UserSettingsGateway($defaults, $this->createMock(SettingsAppGateway::class), $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertSame(12, $gateway->getDefaultRoleId());
+    }
+
+    public function testGetDefaultRoleIdReturnsNullWhenUnset(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->method('getDefaultRoleId')->willReturn(null);
+
+        $gateway = new UserSettingsGateway($defaults, $this->createMock(SettingsAppGateway::class), $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertNull($gateway->getDefaultRoleId());
+    }
+
+    public function testGetDefaultDepartmentIdDelegates(): void
+    {
+        $defaults = $this->createMock(SettingsDefaultsGateway::class);
+        $defaults->method('getDefaultDepartmentId')->willReturn(8);
+
+        $gateway = new UserSettingsGateway($defaults, $this->createMock(SettingsAppGateway::class), $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertSame(8, $gateway->getDefaultDepartmentId());
+    }
+
+    public function testGetAppThemeDelegates(): void
+    {
+        $app = $this->createMock(SettingsAppGateway::class);
+        $app->method('getAppTheme')->willReturn('dark');
+
+        $gateway = new UserSettingsGateway($this->createMock(SettingsDefaultsGateway::class), $app, $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertSame('dark', $gateway->getAppTheme());
+    }
+
+    public function testGetAppThemeReturnsNullWhenUnset(): void
+    {
+        $app = $this->createMock(SettingsAppGateway::class);
+        $app->method('getAppTheme')->willReturn(null);
+
+        $gateway = new UserSettingsGateway($this->createMock(SettingsDefaultsGateway::class), $app, $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertNull($gateway->getAppTheme());
+    }
+
+    public function testAppThemesDelegatesToListThemes(): void
+    {
+        $themes = ['light' => 'Light', 'dark' => 'Dark'];
+        $app = $this->createMock(SettingsAppGateway::class);
+        $app->method('listThemes')->willReturn($themes);
+
+        $gateway = new UserSettingsGateway($this->createMock(SettingsDefaultsGateway::class), $app, $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertSame($themes, $gateway->appThemes());
+    }
+
+    public function testDefaultThemeDelegates(): void
+    {
+        $app = $this->createMock(SettingsAppGateway::class);
+        $app->method('resolveDefaultTheme')->willReturn('light');
+
+        $gateway = new UserSettingsGateway($this->createMock(SettingsDefaultsGateway::class), $app, $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertSame('light', $gateway->defaultTheme());
+    }
+
+    public function testNormalizeThemeDelegates(): void
+    {
+        $app = $this->createMock(SettingsAppGateway::class);
+        $app->method('normalizeTheme')->willReturn('dark');
+
+        $gateway = new UserSettingsGateway($this->createMock(SettingsDefaultsGateway::class), $app, $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertSame('dark', $gateway->normalizeTheme('DARK'));
+    }
+
+    public function testNormalizeThemeWithNullDelegates(): void
+    {
+        $app = $this->createMock(SettingsAppGateway::class);
+        $app->method('normalizeTheme')->willReturn('light');
+
+        $gateway = new UserSettingsGateway($this->createMock(SettingsDefaultsGateway::class), $app, $this->createMock(SettingsUserLifecycleGateway::class));
+        $this->assertSame('light', $gateway->normalizeTheme(null));
+    }
+
+    public function testGetUserInactivityDeactivateDaysDelegates(): void
+    {
+        $lifecycle = $this->createMock(SettingsUserLifecycleGateway::class);
+        $lifecycle->method('getUserInactivityDeactivateDays')->willReturn(180);
+
+        $gateway = new UserSettingsGateway($this->createMock(SettingsDefaultsGateway::class), $this->createMock(SettingsAppGateway::class), $lifecycle);
+        $this->assertSame(180, $gateway->getUserInactivityDeactivateDays());
+    }
+
+    public function testGetUserInactivityDeleteDaysDelegates(): void
+    {
+        $lifecycle = $this->createMock(SettingsUserLifecycleGateway::class);
+        $lifecycle->method('getUserInactivityDeleteDays')->willReturn(365);
+
+        $gateway = new UserSettingsGateway($this->createMock(SettingsDefaultsGateway::class), $this->createMock(SettingsAppGateway::class), $lifecycle);
+        $this->assertSame(365, $gateway->getUserInactivityDeleteDays());
+    }
+}