Relationship to the Canto app

The Canto app lives at pboueke.github.io/canto (source). Canto (the app) is GPLv3-licensed. canto-data (this library) is MIT-licensed to enable data portability: anyone can build tools that interoperate with Canto journals without being bound by the app’s copyleft license.

canto-data (MIT)
└── src/
    ├── types.ts              # All TypeScript interfaces
    ├── validation.ts         # Type guards and structural validators
    ├── version.ts            # Schema version constant and semver utils
    ├── migration.ts          # Forward-only migration runner
    ├── migrations/           # Migration registry
    └── format.ts             # Export manifest and ZIP format utilities

What canto-data owns

• All journal data types (Journal, Page, Attachment, Comment, and related structures)
• Runtime validation and type guards
• Schema versioning and migration framework
• Export format specification (manifest structure and attachment naming)

What it does not include

• Encryption and decryption
• Attachment storage, chunk I/O, and byte reassembly
• Sync integrations and remote uploads
• UI components

Those pieces live in the Canto app — the app also documents its encryption model in SECURITY.md.

The library is MIT-licensed; see LICENSE. The Canto app is a separate GPLv3 project, so the two licenses stay independent: this package ships no app code.