Layerswap Docs

On Starknet, call_data is a JSON-encoded array of calls. It normally contains a token transfer and a Watchdog watch call that lets Layerswap match the deposit. Supported networks: Starknet Mainnet, Starknet Sepolia

[
  {
    "contractAddress": "0xTokenContract",
    "entrypoint": "transfer",
    "calldata": ["0xRecipient", "0xAmountLow", "0xAmountHigh"]
  },
  {
    "contractAddress": "0xWatchdogContract",
    "entrypoint": "watch",
    "calldata": ["0xSequenceNumber"]
  }
]

Submit the complete array atomically — Starknet executes it natively as a single multicall transaction. Do not execute only the transfer or alter the watch call.

Transaction construction

Parse call_data

Deserialize the JSON string into an array of Starknet call objects.

Execute via Account

Pass the calls array to account.execute(). Starknet natively supports multicall, so all calls in the array are executed atomically in a single transaction.

Return the transaction hash

The execute method returns an object with transaction_hash.

Full example

The Server-side tab signs with a raw private key via starknet.js. The Browser tab connects to an injected wallet like ArgentX or Braavos via get-starknet. The starknet-react tab wraps it as a hook for React apps.

import { Account, RpcProvider, type Call } from 'starknet';

async function executeStarknetDeposit(action, senderAddress, privateKey) {
  const provider = new RpcProvider({ nodeUrl: action.network.node_url });
  const account = new Account(provider, senderAddress, privateKey);

  const calls: Call[] = JSON.parse(action.call_data);
  if (!Array.isArray(calls) || calls.length === 0) {
    throw new Error('Invalid Starknet deposit action');
  }

  const { transaction_hash } = await account.execute(calls);
  if (!transaction_hash) {
    throw new Error('No Starknet transaction hash returned');
  }

  // Optionally wait for confirmation.
  await provider.waitForTransaction(transaction_hash);

  return transaction_hash;
}

import { connect } from 'get-starknet';
import { type Call } from 'starknet';

async function executeStarknetDeposit(action) {
  const starknet = await connect();
  if (!starknet?.isConnected || !starknet.account) {
    throw new Error('Starknet wallet not connected');
  }

  const calls: Call[] = JSON.parse(action.call_data);
  if (!Array.isArray(calls) || calls.length === 0) {
    throw new Error('Invalid Starknet deposit action');
  }

  const { transaction_hash } = await starknet.account.execute(calls);
  if (!transaction_hash) {
    throw new Error('No Starknet transaction hash returned');
  }

  return transaction_hash;
}

import { useAccount } from '@starknet-react/core';
import { type Call } from 'starknet';

function useStarknetDeposit() {
  const { account } = useAccount();

  async function executeDeposit(action) {
    if (!account) {
      throw new Error('Starknet account not connected');
    }

    const calls: Call[] = JSON.parse(action.call_data);
    const { transaction_hash } = await account.execute(calls);
    if (!transaction_hash) {
      throw new Error('No Starknet transaction hash returned');
    }

    return transaction_hash;
  }

  return { executeDeposit };
}

Connect the account to the network named in action.network before execution. Store transaction_hash and track the swap.

Start here

Funding

Operations

Recipes

Endpoints

Starknet

Transaction construction

Full example

​Transaction construction

​Full example

Transaction construction

Full example