Gasless Relayer

authenticate()           → Abstraxn server wallet session
createRelayerSigner()    → Abstraxn signs meta-tx (not a local private key)
buildRelayerTxEIP712()   → encode + sign authorization
sendRelayerTx()          → relayer pays gas and calls executeMetaTransaction

import { ServerSignerClient } from '@abstraxn/server-signer';

const client = new ServerSignerClient({
  apiKey: process.env.ABSTRAXN_API_KEY!,
});

// First run: omit accessKey — SDK creates wallet and returns session.accessKey
// Later runs: pass the saved accessKey
const session = await client.authenticate({
  userIdentity: 'my-backend-agent-001',
  accessKey: process.env.SERVER_WALLET_ACCESS_KEY,
});

if (session.didCreate) {
  // Save session.accessKey — required to recover this wallet later
  await saveToSecretsManager(session.accessKey);
}

import { JsonRpcProvider, type Signer } from 'ethers';

const rpcUrl = process.env.RPC_URL!;
const me = await client.whoami<{ result: { address: string; organizationId: string } }>();

const { signer } = client.createRelayerSigner({
  rpcUrl,
  chainId: 137,
  organizationId: me.result.organizationId,
  fromAddress: me.result.address,
});

import { Relayer } from '@abstraxn/relayer';
import { ChainId } from '@abstraxn/core-types';

const relayer = new Relayer({
  relayerUrl: process.env.RELAYER_URL!,
  chainId: ChainId.POLYGON_MAINNET,
  provider: new JsonRpcProvider(rpcUrl),
  signer: signer as unknown as Signer,
});

const buildTxParams = {
  contractAddress: '0xYourContract',
  abi: yourContractAbi,
  method: 'yourMethod',
  args: ['arg1'],
};

// EIP-712 (recommended)
const txData = await relayer.buildRelayerTxEIP712(buildTxParams);

// — or EIP-191 personal sign for legacy contracts:
// const txData = await relayer.buildRelayerTx(buildTxParams);

const { transactionId } = await relayer.sendRelayerTx(txData);
const status = await relayer.getRelayerTxStatus(transactionId);