notification-system-builder

# Notification System Builder ## Overview Builds unified notification systems across email, SMS, push, and in-app channels. ## Decision Framework ### When to use - User needs updates from multiple sources - Multiple delivery channels required - User preferences for notification types needed ### When NOT to use - Simple single-channel alerts - Real-time streaming data ## Decision Tree ``` Is notification user-triggered? ├── Yes → In-app toast + optional email ├── No → Is it time-sensitive? │ ├── Yes → Push notification + SMS fallback │ └── No → Email digest or in-app badge ``` ## Trigger Phrases - "Add notifications" - "Alert users when..." - "Send email when..." - "Push notifications for..." ## Notification Types | Type | Channel | Priority | Retention | |------|---------|----------|-----------| | Transactional | Email + In-app | High | 30 days | | Marketing | Email | Low | 90 days | | System | In-app | Medium | 7 days | | Alert | Push + SMS | Critical | Until read | ## Implementation Patterns ### Preference Schema ```json { "channels": { "email": { "enabled": true, "frequency": "immediate" }, "push": { "enabled": true, "quiet_hours": ["22:00", "08:00"] }, "sms": { "enabled": false }, "in_app": { "enabled": true } }, "types": { "marketing": { "enabled": false }, "updates": { "enabled": true }, "alerts": { "enabled": true } } } ``` ### Delivery Queue ```javascript class NotificationQueue { async enqueue(notification) { const prefs = await this.getUserPreferences(notification.userId); const channels = this.resolveChannels(notification.type, prefs); for (const channel of channels) { await this.queueChannelDelivery(notification, channel); } } } ``` ### Batching Strategy ```javascript const batchWindow = { email: { duration: '1h', maxItems: 10 }, push: { duration: '5m', maxItems: 5 }, sms: { duration: '0', maxItems: 1 } }; ```