Skip to content

README.md

Latest commit

 

History

History
77 lines (55 loc) · 2.65 KB

README.md

File metadata and controls

77 lines (55 loc) · 2.65 KB

@anchr/cashu-conditional-swap

N:M binary outcome conditional swap primitive on Cashu. Brand-neutral — usable beyond Anchr for two-party binary bets, parametric insurance, group bounties, auctions, dispute escrow, anywhere binary outcome settlement is required.

Install

{
  "imports": {
    "@anchr/cashu-conditional-swap": "jsr:@anchr/cashu-conditional-swap@^0.1",
    "@anchr/core-cashu": "jsr:@anchr/core-cashu@^0.1",
    "@anchr/cashu-frost-oracle": "jsr:@anchr/cashu-frost-oracle@^0.1"
  }
}

Two complementary swap mechanisms

Each matched pair forms a bilateral cross-lock: each side's tokens are locked under the counterparty's pubkey and the opposite outcome's hash (or outcome group key in FROST mode). Neither side can redeem alone, the matchmaker never custodies funds, and the Oracle holds only the secret that selects the winner — not the funds themselves.

1. HTLC dual-preimage

Oracle generates two preimages, one per outcome. Tokens are locked with hashlock(outcome_hash) + P2PK(counterparty) + locktime + refund(self). Oracle reveals the winning preimage; the loser's preimage is destroyed (one-time semantics).

2. FROST dual-key

Oracle holds FROST group keypairs, one per outcome. Tokens are locked with P2PK([group_pubkey_outcome, winner_pubkey], n_sigs=2). Oracle signs with the winning side's key; loser's key share is deleted. Per-proof signing via signProofSecrets for NUT-11 P2PK redemption.

Public API

import {
  createSwapPairTokens,
  buildCrossHtlcForPartyA,
  buildCrossHtlcForPartyB,
} from "@anchr/cashu-conditional-swap/cross-htlc";

import {
  createDualPreimageStore,
  type DualPreimageStore,
} from "@anchr/cashu-conditional-swap/dual-preimage-store";

import {
  buildFrostSwapForPartyA,
  buildFrostSwapForPartyB,
  createDualKeyStore,
  type DualKeyStore,
} from "@anchr/cashu-conditional-swap/frost-conditional-swap";

import {
  createFrostDualKeyStore,
  createAdaptiveDualKeyStore,
} from "@anchr/cashu-conditional-swap/frost-dual-key-store";

import type {
  ConditionalSwapDef, FrostConditionalSwapDef, SwapPair,
} from "@anchr/cashu-conditional-swap/conditional-swap-types";

Tests

deno task test

Tests cover all HTLC / FROST swap scenarios + 6 attack scenarios (locktime race, dual signing, cross-market replay, per-proof mismatch, FROST collusion, double-spend).

Dependencies

  • @anchr/core-cashu — EscrowToken, escrow helpers, preimage store
  • @anchr/cashu-frost-oracle — FROST signing coordination
  • @cashu/cashu-ts — Cashu protocol (P2PK, HTLC builders)
  • @noble/curves, @noble/hashes, nostr-tools — Schnorr signing primitives

License

MIT