3sendxyz App

Desktop app (Electron + React + TypeScript) for free encrypted file transfers on top of existing https://3send.xyz APIs.

Current scope

• App-generated local secp256k1 private key (EVM address) on first run
• Free encrypted send flow (micro tier)
• Inbox list + download + decrypt (vault mode)
• Outbox list
• Settings page with app address

Out of scope in this phase:

• Paid sends (R1/USDC/ETH)
• Key backup/import/export
• Automated tests

Requirements

• Node.js 20+
• npm
• macOS Keychain or Windows Credential Manager (via keytar)

Run locally

npm install
npm run dev

npm run dev starts Vite and Electron together via vite-plugin-electron.

Validate

npm run lint
npm run build

Packaging

npm run dist
npm run dist:mac
npm run dist:win
npm run dist:release

Notes:

• dist command builds and packages the current platform.
• dist:mac builds a universal macOS binary (arm64 + x64).
• Cross-platform packaging requirements depend on host environment.
• Builds are signed automatically when signing credentials are available in environment variables.

Signing setup

macOS signing + notarization (build on macOS):

• APPLE_API_KEY
• APPLE_API_KEY_ID
• APPLE_API_ISSUER
• CSC_LINK and CSC_KEY_PASSWORD for the Developer ID Application certificate (or certificate installed in Keychain discoverable by electron-builder)

Alternative macOS notarization auth is also supported by electron-builder:

• APPLE_ID, APPLE_APP_SPECIFIC_PASSWORD, APPLE_TEAM_ID

Windows code signing:

• CSC_LINK (path/URL/base64 to .p12/.pfx certificate)
• CSC_KEY_PASSWORD

When these variables are present, electron-builder signs Windows artifacts and signs/notarizes macOS artifacts using the config in package.json.

GitHub Release Workflow

Workflow: /Users/alessandro/programmazione/3send/3sendxyz-app/.github/workflows/release.yml

• Trigger: push a tag matching v* (example: v0.2.0)
• Jobs:
  • build signed/notarized macOS artifacts
  • build signed Windows artifacts
  • publish all artifacts into a GitHub Release for that tag

Required repository secrets:

• CSC_LINK
• CSC_KEY_PASSWORD
• macOS notarization:
  • APPLE_API_KEY, APPLE_API_KEY_ID, APPLE_API_ISSUER
  • or APPLE_ID, APPLE_APP_SPECIFIC_PASSWORD, APPLE_TEAM_ID
• Optional Windows-specific override:
  • WIN_CSC_LINK
  • WIN_CSC_KEY_PASSWORD

Website dependency

This app expects https://3send.xyz API routes to be reachable cross-origin.

@software{butusina2025_3sendxyz_app,
  author       = {Butusina, Petrica and Defranceschi, Alessandro},
  title        = {{3sendxyz App}: End-to-end encrypted, decentralized file transfer downloadable app},
  year         = {2025},
  url          = {https://github.com/3lemmalabs/3sendxyz-app},
  organization = {3lemma Labs},
  note         = {Software library}
}