System Architecture

Runtime Components

• Electron desktop app: clipboard listener, sender, receiver, screenshot and branding workflows
• Mobile/PWA client: paired sync receiver and sender, private-share receiver
• Next.js backend: auth, APIs, release metadata, and web routes
• Socket relay: encrypted real-time routing for clip sync and file/share events

Trust Boundaries

Device boundary: encryption/decryption and key handling stay on client devices.

Relay boundary: backend relays encrypted payloads and metadata required for routing.

Storage boundary: account/subscription data is stored server-side; user content is not persisted in plaintext.

Core Data Flows

• Clipboard sync: authenticated socket -> encrypted envelope -> recipient device
• Private share: sender creates session -> receiver joins -> encrypted chunks streamed via relay
• Secure drop/tunnel: scoped session IDs with explicit sender/receiver states and cleanup

Current Limits

• Text payload up to 1 MB
• Image payload up to 10 MB
• File chunk size up to 512 KB
• Max file transfer size up to 100 MB
• Max concurrent connected devices per user: 10