evernote-reference-architecture

# Evernote Reference Architecture ## Overview Production-ready architecture patterns for building scalable, maintainable Evernote integrations. Covers service layer design, caching strategy, sync architecture, and deployment topology. ## Prerequisites - Understanding of microservices or modular monolith architecture - Cloud platform familiarity (AWS, GCP, or Azure) - Knowledge of message queues and caching ## Instructions ### Architecture Layers ``` Client Layer [Web App / Mobile / CLI] | API Layer [Express/Fastify REST API] | Service Layer [NoteService | SearchService | SyncService] | Integration [EvernoteClient (rate-limited, instrumented)] | Infrastructure [Redis Cache | PostgreSQL | Message Queue] ``` ### Service Layer Design Separate concerns into focused services: - **NoteService**: CRUD operations, ENML formatting, tag management - **SearchService**: Query building, pagination, result enrichment - **SyncService**: Webhook handling, incremental sync, conflict resolution - **AuthService**: OAuth flow, token storage, refresh logic ```javascript // services/index.js - Service registry class ServiceRegistry { constructor(noteStore, cache, db) { this.notes = new NoteService(noteStore); this.search = new SearchService(noteStore, cache); this.sync = new SyncService(noteStore, db); } } ``` ### Caching Strategy Cache at two levels: in-memory L...