Task 006: Change Detection & Diff Engine

[AustinZ21]

Description

Implement intelligent change detection system with versioned snapshots and diff algorithms. Build notification engine that alerts users to privacy setting changes across platforms with impact assessment.

Acceptance Criteria

• Snapshot versioning system with efficient diff comparison
• Change detection algorithms identifying meaningful privacy changes
• Notification system with configurable alerting preferences
• Historical change tracking with impact analysis and reporting

Technical Details

Snapshot Versioning System

interface PrivacySnapshot {
  id: string;
  user_id: string;
  platform_id: string;
  version: number;
  settings_hash: string;
  compressed_data: CompressedSettings;
  created_at: Date;
}

interface ChangeDetection {
  detectChanges(previous: PrivacySnapshot, current: PrivacySnapshot): PrivacyDiff[];
  assessImpact(changes: PrivacyDiff[]): ImpactAssessment;
  generateNotifications(changes: PrivacyDiff[]): NotificationEvent[];
}

Diff Algorithm Implementation

• Intelligent diff comparison beyond simple value changes
• Privacy-aware change classification (critical, important, minor)
• Template-based diff storage for space efficiency
• Change aggregation and deduplication logic

Change Notification System

• User-configurable notification preferences (email, push, dashboard)
• Change severity classification and filtering
• Notification scheduling and rate limiting
• Rich notification content with context and recommendations

Impact Analysis Engine

• Privacy impact scoring based on setting importance
• Historical trend analysis for privacy degradation detection
• Platform-specific impact weighting and context
• User privacy goal alignment assessment

Dependencies

• Task 002: Requires database schema for privacy_snapshots and notifications
• Task 004: Requires scraping engine data as input for change detection
• Email service for change notifications (from Task 003 auth system)

Effort Estimate

Medium (2-3 days)

• Day 1: Snapshot versioning and core diff algorithm implementation
• Day 2: Change detection logic and impact analysis engine
• Day 3: Notification system integration and historical reporting

Definition of Done

• Change detection accurately identifies meaningful privacy setting changes
• Notification system delivers timely alerts based on user preferences
• Snapshot versioning efficiently stores historical data with minimal overhead
• Impact analysis provides actionable insights on privacy degradation
• Historical reporting shows privacy trends and platform behavior patterns

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