Start Accepting Letters of Credit in Your App

Launch a ready-made creation flow with your product requirements built in. Simply set the terms your product controls in one typed config, then let customers fill in the rest.

Get access Open the configurator

booking-form.tsx

import { AnvilProvider, CreateLOCFlow } from '@anvil/sdk';
import { AnvilSDK, testnetProfile, type LOCConfig } from '@anvil/sdk/core';

// Terms your product sets. The form shows them and nobody can change
// them; the customer picks the amount and what backs it.
const locConfig: LOCConfig = {
  // The hotel, which the form shows by its ENS name, grandmeridian.eth.
  beneficiary: { value: '0x45f53BE3459Cd14324967e8EAe6d8965DE611625' },
  expiration: { value: new Date('2027-06-30T12:00:00Z') },
};

const sdk = new AnvilSDK({
  profile: testnetProfile,
  publicClient,
  locConfig,
});

export function GuaranteeYourBooking() {
  return (
    <AnvilProvider sdk={sdk}>
      <CreateLOCFlow
        createOnly
        title="Guarantee your booking"
        description="Hold your room without paying upfront."
      />
    </AnvilProvider>
  );
}

Guides

Start Building

Choose the integration path that fits your product, from a form you drop into a React app to a job that runs the whole lifecycle.

Try it

Read a Live LOC

Every Letter of Credit lives onchain and can be read without a wallet or signup. This is the same call your app would make, running directly in your browser against the public testnet.

read-loc.ts

import { createPublicClient, http } from 'viem';
import { sepolia } from 'viem/chains';

import { AnvilSDK, testnetProfile } from '@anvil/sdk/core';

const publicClient = createPublicClient({
  chain: sepolia,
  transport: http(),
});
const sdk = new AnvilSDK({ profile: testnetProfile, publicClient });

export async function readLOC(id: bigint) {
  // Who it's for, what it promises, and everything since.
  return sdk.loc.getLetterOfCredit({ id });
}

// The latest LOCs load here; pick one to read its full record.

Testnet

Use cases

Where Letters of Credit Fit

A Letter of Credit can stand in for a deposit, a prepayment, or a bank guarantee. Pick a use case to see how it runs and the code behind it.

Let guests book without paying upfront

Book1,200 USDCThe guest reserves the amount for the hotel instead of paying a deposit.
No-showIf the guest doesn’t arrive, the hotel redeems its no-show fee.
Check outThe hotel cancels the LOC, and the guest’s collateral is released at once.

Add a create-LOC form to your app →LOCs for reservations ↗

use-cases.ts

// The guest guarantees the stay, and the hotel is the Beneficiary.
const booking = {
  beneficiary: hotel,
  tokenAmount: { tokenAddress: USDC, amount: 1_200_000000n },
  expirationTimestampSeconds: dateToEthereumTimestamp(checkout),
};

const issues = await sdk.loc.validateCreateStatic(booking);
if (issues.length === 0) {
  await (await sdk.loc.buildCreateStaticWorkflow(booking)).execute();
}

Secure an order before the container ships

Order480,000 USDCThe importer backs the order with a Letter of Credit that runs 120 days.
ShipBefore each shipment, the exporter reads what is still guaranteed.
DeliverThe exporter redeems as the goods arrive. Either side can verify the LOC at any time.

Create and redeem a LOC →LOCs for global trade ↗

use-cases.ts

// Before each shipment, the exporter reads what is still guaranteed,
// straight from the contract.
const live = await sdk.loc.getOutstandingLetterOfCredit({ id });

if (live && live.remainingCredited.amount >= invoice) {
  await releaseShipment();
}

Verify player funds without holding them

Back5,000 USDTThe player backs their play with a Letter of Credit.
PlayThe operator sees exactly how much is guaranteed.
SettleThe operator redeems losses and never holds the player’s funds.

Monitor LOCs and vault state →Example use cases ↗

use-cases.ts

// Every open LOC this player has backed for the operator.
const page = await sdk.loc.getLetterOfCredits({
  creators: [player],
  beneficiaries: [operator],
  outstanding: true,
});

const guaranteed = page.items.reduce(
  (sum, loc) => sum + (loc.outstanding?.remainingCredited.amount ?? 0n),
  0n
);

Lend against crypto without taking custody

Borrow4,000 USDCThe borrower reserves 2 WETH to back the credit with a Dynamic LOC.
PriceThe SDK fetches a fresh oracle price for the transaction.
ProtectIf WETH falls too far, the protocol converts the collateral, so the lender is still paid.

Prices and the oracle →LOCs for consumer lending ↗

use-cases.ts

// 2 WETH of collateral backs 4,000 USDC of credit. A fresh oracle price
// travels with the transaction.
const priceUpdate = await sdk.pricing.getOraclePriceUpdate({
  inputToken: WETH,
  outputToken: USDC,
});

const loan = await sdk.loc.buildCreateDynamicWorkflow({
  beneficiary: lender,
  creditedTokenAmount: { tokenAddress: USDC, amount: 4_000_000000n },
  collateralTokenAmount: { tokenAddress: WETH, amount: 2n * 10n ** 18n },
  expirationTimestampSeconds: dateToEthereumTimestamp(dueDate),
  priceUpdate,
});
await loan.execute();

Security

Built on Audited Institutional-Ready Infrastructure

Four independent audits
OpenZeppelin and Trail of Bits reviewed the contracts, 2023 to 2025.
Two public bug bounties
Immunefi competitions on Letters of Credit and the Collateral Vault.
Live on Ethereum
Every LOC and the collateral behind it can be checked onchain by anyone.
Readable by your AI tools
Every page is also plain Markdown, indexed in llms.txt.

Make Every Financial Commitment Fully Secured Onchain

The SDK is in partner preview. Tell us what you’re building, and we’ll set you up with the package and a direct line to the team.

Get access Read the guides