Installation
npm install @biconomy/abstractjs viem
Basic Setup
import {
createMeeClient,
toMultichainNexusAccount,
getMEEVersion,
MEEVersion
} from "@biconomy/abstractjs";
import { http } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { base, optimism } from "viem/chains";
// 1. Create a signer (user's wallet)
const signer = privateKeyToAccount(process.env.PRIVATE_KEY as `0x${string}`);
// 2. Create multichain account
const account = await toMultichainNexusAccount({
signer,
chainConfigurations: [
{ chain: optimism, transport: http(), version: getMEEVersion(MEEVersion.V2_1_0) },
{ chain: base, transport: http(), version: getMEEVersion(MEEVersion.V2_1_0) }
]
});
// 3. Create MEE client
const meeClient = await createMeeClient({ account });
Lazy Deployment: Accounts aren’t deployed until the first transaction on each chain. Only addresses are calculated upfront.
Configuration Options
Account Parameters
| Parameter | Description | Required |
|---|
signer | User wallet (EOA) that owns the account | Yes |
chainConfigurations | Array of chain configs | Yes |
chainConfigurations[].chain | Viem chain object | Yes |
chainConfigurations[].transport | RPC transport | Yes |
chainConfigurations[].version | MEE version | Yes |
chainConfigurations[].accountAddress | Override for EIP-7702 | No |
MEE Client Parameters
| Parameter | Description | Required |
|---|
account | The multichain account | Yes |
apiKey | API key for sponsorship | No |
EIP-7702 Mode
For embedded wallets (Privy, Dynamic, Turnkey), use EIP-7702 by setting accountAddress to the EOA:
const account = await toMultichainNexusAccount({
signer,
chainConfigurations: [
{
chain: base,
transport: http(),
version: getMEEVersion(MEEVersion.V2_1_0),
accountAddress: signer.address // Use EOA directly
}
]
});
Get Account Addresses
// Get address on a specific chain
const baseAddress = account.addressOn(base.id);
// Get address with strict mode (throws if chain is not defined in chainConfigurations)
const strictAddress = account.addressOn(base.id, true);
Both calls return the same address. The true flag enables strict mode, which throws an error if the chain is not defined in your chainConfigurations. This helps catch configuration mistakes early.
Next Steps
