Security model

Locked Vaults

  • One-time vault per link. Each claim link gets its own ephemeral ed25519 keypair, generated in your browser, that briefly holds the USDC. Its private key never leaves the server unencrypted.
  • Encrypted with your code. The vault key is sealed with AES-GCM using a key derived from your secret — funds only move when the correct code decrypts it.
  • No double-claims. The claim transaction moves the vault's entire balance and closes its token account, draining it to zero — atomically, even under concurrent attempts.
  • Brute-force resistant. Repeated wrong codes trigger temporary lockouts, and PayLink never custodies your keys.
Locked vault secured by a secret code