Cross Chain Signatures

Chain signatures enable NEAR to sign and execute transactions across multiple blockchains via an MPC (Multi-Party Computation) network. Fortunately, to implement this functionality in your DApp, you won't need to integrate MPC directly, as it's fully operational within Bitte Wallet. Building an EVM transaction is straightforward once you've established a basic connection with the wallet. Redirect to the wallet URL with the evmTx parameter and the wallet will handle the complexities of generating the EVM signature and sending the transaction.

Note: This functionality currently only works for the NEAR testnet.

import { BaseTx, setupAdapter } from "near-ca";

const accountId = "your-account.testnet";
const network = {
  networkId: "testnet",
  nodeUrl: "https://rpc.testnet.near.org",
};

const adapter = await setupAdapter({ accountId, network });

// Build your favourite transaction!
const baseTx: BaseTx = {
  to: "0xDEADBEEF00000000000000000000000000000000",
  value: 1n,
  chainId: 11_155_111,
  data: "0x",
};

// This will attach gas, fees and nonce to transaction.
const { transaction } = await adapter.createTxPayload(baseTx);

// Pass the serialized transaction to this url route.
const route = `https://wallet.bitte.ai/sign-evm?evmTx=${transaction}&callback_url=https://yourdappurl.xyz`;

// Redirect to our wallet URL with the transaction to be sent, once successful user will be redirected to callback_url

Check out NEAR-CA if you would like to implement MPC directly without using a wallet, or to take advantage of its various utilities for interfacing between NEAR and EVM.

npm: near-canpm