My Signet

Identity verification app for the Signet protocol. Verify your identity once, prove claims about yourself anywhere — without revealing personal data.

Built on Nostr using the Signet Protocol.

What it does

• Create an identity from a BIP-39 mnemonic with dual keypairs (Natural Person + Persona)
• Import from existing backup words or Nostr nsec key
• Add family members via QR code or Signet ID — verified with directional spoken-token words
• Get verified by a professional (GP, solicitor, teacher) — in-person credential ceremony
• Verify someone else — issue two credentials (identity + anonymous persona)
• Prove your age to websites via QR scan — no personal data shared, only age range and tier
• Sign in with Signet — websites redirect to mysignet.app, user approves, redirected back with cryptographic proof
• Log in to Nostr apps via NIP-46 remote signing
• Sign for Android apps on the same phone as a NIP-55 signer: Amethyst, KithMoot and anything Amber-shaped find "My Signet" in their signer list, ask once, and can be allowed always. Settings → Connected Sites lists them under "Apps on this phone", where an allow-always is taken back. For five minutes after serving one, My Signet keeps its key while hidden behind that app, so an allowed-always app signs without a PIN each time
• Back up via Shamir secret sharing (2-of-3)
• Manage connections — view and revoke sites you've signed in to

Security

• Private keys encrypted at rest with AES-256-GCM (PBKDF2 600k iterations)
• WebAuthn biometric auth with PRF extension (hardware-derived keys where supported)
• PIN fallback with brute-force lockout (30s → 5m → 1h)
• Auto-lock on inactivity (15 min) and tab switch (with 60s grace during active verification)
• All relay events are signed NIP-01 events
• Content Security Policy — no unsafe-eval, no unsafe-inline scripts
• Relay URL validation — wss:// required for production, ws:// only for localhost
• QR input validation — hex format, timestamp freshness, origin-callback matching, max payload size
• URL auth validation — required timestamps, origin scheme enforcement, callback origin matching
• Sensitive data auto-hidden after 90 seconds (mnemonic, Shamir shares)
• Clipboard auto-cleared after 60 seconds
• NIP-44 key material zeroized after use
• No console output in production code
• Three-round security audit completed (April 2026)

Quick start

npm install
npm run dev        # starts on https://localhost:5174 (or http if no certs)

For HTTPS (required for WebAuthn on non-localhost):

mkdir cert
# Generate self-signed cert:
mkcert -key-file cert/signet-key.pem -cert-file cert/signet.pem localhost
npm run dev

Build

npm run build      # outputs to dist/
npm run preview    # preview production build
npm run typecheck  # TypeScript type checking

Sign in with Signet

External websites can authenticate users via a redirect flow:

1. Website redirects to https://mysignet.app/?auth=1&challenge={hex}&origin={url}&name={name}&callback={url}&t={timestamp}
2. User unlocks the app and sees an approval screen showing what will be shared
3. On approve, the app signs the challenge and redirects back to {callback}?pubkey={hex}&npub={bech32}&signature={hex}&eventId={hex}
4. On deny, redirects to {callback}?error=denied

Architecture

React 19 SPA with no router library — page state managed in App.tsx. All data stored client-side in IndexedDB v3 (via idb).

src/
├── lib/           — Core logic (crypto, storage, relay, QR routing, URL auth)
├── hooks/         — React hooks (identity, family, credentials, relay, connections)
├── pages/         — Full-page views (20 pages: onboarding, home, verify, settings, connections)
├── components/    — Shared UI components (QR, badges, navigation)
├── types.ts       — TypeScript interfaces
└── App.tsx        — Main app component, page routing, URL auth handler

Dependencies

• signet-protocol — Protocol library (nsec-tree key derivation, credentials, badges, Shamir)
• spoken-token — Directional word verification for Signet Me
• @noble/curves + @noble/hashes + @noble/ciphers — Cryptographic primitives
• idb — IndexedDB wrapper
• qrcode + html5-qrcode + jsqr — QR generation and scanning

Known limitations

• PIN lockout state is stored in localStorage. An attacker with device-level access could clear it to bypass rate limiting. This is defense-in-depth — the primary protection is AES-256-GCM decryption which requires the correct PIN regardless of lockout state.
• Auth responses and credentials published to relays are not NIP-44 encrypted (architectural design decision pending).
• Identity documents and stored credentials in IndexedDB are not encrypted at rest (encryption key threading design decision pending).

License

MIT