# Architecture Analysis Example

> This is an example of the architecture analysis that Gjalla posts to GitHub Pull Request checks

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## 🟡 Medium Risk

**Risk Tags:** surface-area-change, behavior-change

### 🏛️ Architecture Elements
- ✨ **NotificationPreferencesService** (added): New service for managing user notification preferences across email, SMS, and push channels
- ✨ **notifications_preferences** (added): Database table storing user notification settings with foreign key to users table
- 📝 **UserAPIRouter** (modified): Added GET and PUT endpoints for /api/users/:id/notification-preferences with user ownership validation
- 📝 **UserSettingsPanel** (modified): Extended with new notification preferences section allowing channel-specific configuration
- 📝 **EmailService** (modified): Updated to check user notification preferences before sending emails

### 🎯 Capability Changes
- ✨ **New**: User Notification Preferences Management - Users can configure notification preferences across email, SMS, and push channels
- 📝 **Enhanced**: User Settings Management - Extended with notification preferences section

### ⚠️ Rule Violations
- None detected ✅

### 🧭 Implicit Architecture Decisions

- 🔴 **Notification preferences owned by user domain** (data-ownership)
  - 💡 Consider: Document this as a decision: User Service Owns Notification Preferences

- 🟡 **Synchronous preference validation** (api-contract)
  - 💡 Consider: Should preference updates be eventually consistent or immediately validated?

### 📊 Impact Assessment
This change introduces a new subdomain within the user service for managing notification preferences. The implementation maintains architectural consistency by following established patterns for service-layer business logic and RESTful API design. The addition is well-scoped and doesn't create new cross-service dependencies. Database migration is straightforward with proper foreign key constraints. The change enables future notification features while maintaining backward compatibility.

### ⚠️ Breaking Changes
- None

### 🔄 Migration Notes
Run database migration to add `notifications_preferences` table before deploying. Default behavior for existing users: all notification channels enabled to maintain current notification delivery behavior.

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