code: func GenPrivKeyEd25519FromSecret(secret []byte) PrivKeyEd25519 {
  	privKey32 := Sha256(secret) // Not Ripemd160 because we want 32 bytes.
  	privKeyBytes := new([64]byte)
  	copy(privKeyBytes[:32], privKey32)
  	ed25519.MakePublicKey(privKeyBytes)
  	return PrivKeyEd25519(*privKeyBytes)
  }
docs: // NOTE: secret should be the output of a KDF like bcrypt,
  // if it's derived from user input.