Dropbox Pc App — Recent & Instant

| Component | Implementation | |-----------|----------------| | Sync Engine | Custom C++ library, event-driven (using Windows change journals) | | File System Integration | Shell extension (overlay icons, context menus), Windows API hooks | | Database | Local SQLite tracking file metadata and sync state | | Network | TLS 1.2/1.3, HTTP/3 (QUIC) for upload/download | | Background Service | DropboxUpdateService (runs even when UI is closed) |