Encrypted, private, local-first note manager — end-to-end encrypted (E2EE) sync edition

Carro Note is a privacy-focused note-taking app: all notes are encrypted at rest on your device by default (AES-256-GCM), with no dependency on any third-party cloud.

This project is a fork of the upstream keshav-space/safenotes with extensive modifications. The centerpiece is a complete end-to-end encrypted multi-device sync subsystem: a client-side SyncEngine + a pluggable backend abstraction (WebDAV / self-hosted HTTP service / local filesystem), accompanied by two reference server implementations (SafeServer) in Go and Node.js.

Core capabilities (inherited from upstream)

• Local AES-256 encrypted storage; notes never touch disk in plaintext
• Biometric unlock (fingerprint / face)
• Android background snapshot protection, stealth keyboard, screenshot protection
• Brute-force protection, inactivity auto-lock guard
• Arctic Nord light/dark theme, list/grid views, colored notes
• Encrypted backup export/import (seamless migration to a new device)
• Multi-language UI (Simplified & Traditional Chinese included)

New capabilities (this fork)

• End-to-end encrypted sync: MK + dataKey two-layer key hierarchy, password change in O(1), atomic
• Backend-agnostic: WebDAV (Jianguoyun / NextCloud / self-hosted), self-hosted SafeServer HTTP, or local filesystem
• Content-addressable (content hash) storage with natural deduplication; soft-delete / tombstone sync
• Multi-device sync + LWW conflict resolution + historical version retention
• Sync diagnostics page, sync status visualization
• Markdown editor with live preview
• Note tags, pinning, and per-note lock
• Customizable theme seed color
• Cross-platform: Windows / Android / iOS / Web

lib/               Flutter client: UI, state assembly, platform injection (entry: lib/main.dart)
packages/core/     Pure-Dart core package: crypto, SQLite DB, models, SyncEngine (no Flutter dependency)
bin/               Pure-Dart CLI client: reads/writes the encrypted DB without the Flutter SDK
server/            SafeServer reference implementations in Go and Node.js (committed; only its `data/` and `dist/` artifacts are git-ignored)
docs/              Design docs, protocol specs, and the developer guide
test/              App-side and integration tests

The core logic (crypto / database / sync engine) lives in a pure Dart package packages/core (Flutter dependencies are forbidden and enforced by the pub workspace compiler). The app side only keeps UI and state assembly, importing through the single entry point package:core/core.dart. A pure Dart CLI bin/safenotes_cli.dart is also provided (read/write the encrypted note database without the Flutter SDK; can be compiled to an AOT native binary).

• Developer guide — code structure, build, and testing workflow: docs/DEVELOPMENT.md
• Detailed design, protocol specs, and daily change logs live in the docs/ directory (see docs/DEVELOPMENT.md for an index).

GPL-3.0-or-later. © Keshav Priyadarshi and others. See LICENSE, AUTHORS.md, SECURITY.md.