Privacy-First Personalization

// On-device preference learning
class LocalPreferenceModel {
  private db: IDBDatabase;
  private embedder: Pipeline;

  async learnFromBehavior(signal: BehaviorSignal) {
    // Generate embedding for the interaction
    const embedding = await this.embedder(signal.context);

    // Update local preference weights
    const update = {
      category: signal.productCategory,
      weight: this.calculateWeight(signal),
      embedding: Array.from(embedding.data),
      timestamp: Date.now()
    };

    // Store in IndexedDB (never sent to server)
    await this.db.put('preferences', update);
  }

  async getPersonalizedRanking(products: Product[]) {
    const preferences = await this.db.getAll('preferences');

    return products.map(p => ({
      ...p,
      relevanceScore: this.computeRelevance(p, preferences)
    })).sort((a, b) => b.relevanceScore - a.relevanceScore);
  }

  // User controls their data
  async exportData() {
    return await this.db.getAll('preferences');
  }

  async deleteAllData() {
    await this.db.clear('preferences');
  }
}