@hashlock/sdk

TypeScript SDK for HashLock — institutional OTC trading with HTLC atomic settlement on Ethereum and Bitcoin.

Install

npm install @hashlock/sdk
# or
pnpm add @hashlock/sdk

Quick Start

import { HashLock } from '@hashlock/sdk';

const hl = new HashLock({
  endpoint: 'http://142.93.106.129/graphql',
  accessToken: 'your-jwt-token',
});

// Create an RFQ to sell 1 ETH for USDT
const rfq = await hl.createRFQ({
  baseToken: 'ETH',
  quoteToken: 'USDT',
  side: 'SELL',
  amount: '1.0',
});

console.log(`RFQ created: ${rfq.id}`);

Authentication

Get a JWT token by logging into the HashLock platform, then pass it to the SDK:

const hl = new HashLock({
  endpoint: 'http://142.93.106.129/graphql',
  accessToken: 'eyJhbGciOiJIUzI1NiIs...',
});

// Or update the token later
hl.setAccessToken('new-token');

RFQ Trading

Create an RFQ (Request for Quote)

const rfq = await hl.createRFQ({
  baseToken: 'BTC',
  quoteToken: 'USDT',
  side: 'BUY',
  amount: '0.5',
  expiresIn: 300, // 5 minutes
});

Respond with a Quote

const quote = await hl.submitQuote({
  rfqId: rfq.id,
  price: '68500.00',
  amount: '0.5',
});

Accept a Quote (creates a Trade)

const accepted = await hl.acceptQuote(quote.id);
// accepted.trade.id -> trade ready for settlement

List & Query

const { rfqs, total } = await hl.listRFQs({ status: 'ACTIVE', page: 1 });
const rfq = await hl.getRFQ('rfq-uuid');
const quotes = await hl.getQuotes('rfq-uuid');

HTLC Settlement — ETH / ERC-20

After a trade is accepted, both parties lock assets in HTLC contracts.

Record an HTLC Lock (after on-chain tx)

// 1. Send ETH lock tx on-chain via ethers.js / viem
// 2. Record it in HashLock:
const result = await hl.fundHTLC({
  tradeId: 'trade-uuid',
  txHash: '0xabc123...',
  role: 'INITIATOR',
  timelock: Math.floor(Date.now() / 1000) + 3600,
  hashlock: '0xdef456...',
  chainType: 'evm',
});

Claim an HTLC (reveal preimage)

const claimed = await hl.claimHTLC({
  tradeId: 'trade-uuid',
  txHash: '0xclaim...',
  preimage: '0xsecret...',
  chainType: 'evm',
});

Refund (after timelock expiry)

const refunded = await hl.refundHTLC({
  tradeId: 'trade-uuid',
  txHash: '0xrefund...',
});

Check HTLC Status

const status = await hl.getHTLCStatus('trade-uuid');
console.log(status?.initiatorHTLC?.status);    // 'ACTIVE'
console.log(status?.counterpartyHTLC?.status);  // 'PENDING'

HTLC Settlement — Bitcoin

Bitcoin HTLCs use P2WSH scripts (no smart contract deployment needed).

Prepare a Bitcoin HTLC

const btcHtlc = await hl.prepareBitcoinHTLC({
  tradeId: 'trade-uuid',
  role: 'INITIATOR',
  senderPubKey: '02abc...',    // 33-byte compressed pubkey
  receiverPubKey: '03def...',
  timelock: Math.floor(Date.now() / 1000) + 7200,
  amountSats: '100000',        // 0.001 BTC
});

console.log(`Send BTC to: ${btcHtlc.htlcAddress}`);
// Fund this P2WSH address with your Bitcoin wallet

Claim a Bitcoin HTLC

// Build unsigned PSBT
const psbt = await hl.buildBitcoinClaimPSBT({
  tradeId: 'trade-uuid',
  htlcId: btcHtlc.htlcId,
  preimage: '0xsecret...',
  destinationPubKey: '02abc...',
  feeRate: 10, // sat/vB
});

// Sign with wallet (Xverse, Leather, UniSat, etc.)
const signedTx = await wallet.signPsbt(psbt.psbtBase64);

// Broadcast
const broadcast = await hl.broadcastBitcoinTx({
  tradeId: 'trade-uuid',
  txHex: signedTx,
});
console.log(`BTC claimed: ${broadcast.txid}`);

Cross-Chain Atomic Swap (ETH ↔ BTC)

// Alice (ETH side) locks USDT on Ethereum
await hl.fundHTLC({
  tradeId, txHash: evmTxHash, role: 'INITIATOR',
  hashlock, timelock: now + 7200, chainType: 'evm',
});

// Bob (BTC side) locks BTC on Bitcoin
const btc = await hl.prepareBitcoinHTLC({
  tradeId, role: 'COUNTERPARTY',
  senderPubKey: bobPub, receiverPubKey: alicePub,
  timelock: now + 3600, amountSats: '100000',
});
// Bob funds the P2WSH address, then:
await hl.fundHTLC({
  tradeId, txHash: btcFundingTxid, role: 'COUNTERPARTY',
  chainType: 'bitcoin', redeemScript: btc.redeemScript,
});

// Alice claims BTC (reveals preimage)
// Bob sees preimage on-chain → claims USDT on Ethereum
// Trade complete!

Error Handling

import { HashLockError, GraphQLError, AuthError, NetworkError } from '@hashlock/sdk';

try {
  await hl.getTrade('bad-id');
} catch (err) {
  if (err instanceof AuthError) {
    // Token expired — refresh and retry
  } else if (err instanceof GraphQLError) {
    console.error('API error:', err.errors);
  } else if (err instanceof NetworkError) {
    console.error('Network issue:', err.message);
  }
}

Configuration

const hl = new HashLock({
  endpoint: 'http://142.93.106.129/graphql', // mainnet
  accessToken: 'jwt-token',
  timeout: 30000,    // 30s (default)
  retries: 3,        // retry count (default)
});

Option	Type	Default	Description
endpoint	string	—	GraphQL API URL (required)
accessToken	string	—	JWT bearer token
timeout	number	30000	Request timeout (ms)
retries	number	3	Retry attempts for transient failures
fetch	typeof fetch	globalThis.fetch	Custom fetch implementation

Mainnet Contracts (Ethereum)

Contract	Address
HashedTimelockEther	0x0CEDC56b17d714dA044954EE26F38e90eC10434A
HashedTimelockEtherFee	0xfBAEA1423b5FBeCE89998da6820902fD8f159014
HashedTimelockERC20Fee	0x4B65490D140Bab3DB828C2386e21646Ed8c4D072

License

MIT