Staging MEE Node
By default, AbstractJS connects to the production MEE node which operates on mainnets. To work with testnets during development, you need to target the staging MEE node instead.
Use the getDefaultMEENetworkUrl() and getDefaultMEENetworkApiKey() helper functions with true to connect to the staging environment:
import {
createMeeClient,
toMultichainNexusAccount,
getDefaultMEENetworkUrl,
getDefaultMEENetworkApiKey,
getMEEVersion,
MEEVersion
} from "@biconomy/abstractjs";
import { http } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { sepolia, baseSepolia } from "viem/chains";
// 1. Create a signer
const signer = privateKeyToAccount(process.env.PRIVATE_KEY as `0x${string}`);
// 2. Create multichain account with testnet chains
const account = await toMultichainNexusAccount({
signer,
chainConfigurations: [
{ chain: sepolia, transport: http(), version: getMEEVersion(MEEVersion.V2_1_0) },
{ chain: baseSepolia, transport: http(), version: getMEEVersion(MEEVersion.V2_1_0) }
]
});
// 3. Create MEE client targeting staging node
const meeClient = await createMeeClient({
account,
url: getDefaultMEENetworkUrl(true), // isStaging = true
apiKey: getDefaultMEENetworkApiKey(true)
});
isStaging parameter (set to true) tells the SDK to:
- Connect to the staging MEE orchestrator URL
- Use the staging API key for authentication
Production vs Staging: When you’re ready to deploy to mainnet, simply remove the url and apiKey parameters (or pass false) to use the production defaults.
Important Considerations
Limited Multichain Support on TestnetsTestnets have significant limitations for cross-chain operations:
- Bridges: Most bridge protocols don’t support testnets or have limited testnet deployments
- Solvers: Liquidity solvers typically don’t operate on testnets
- DEX Liquidity: Testnet DEXes often lack the liquidity needed for realistic testing
This means multichain orchestration features (cross-chain swaps, bridging, etc.) may not work reliably in testnet environments. What Works Well on Testnets
- Single-chain transactions and batching
- Gas estimation and simulation
- Smart account deployment and configuration
- Session key setup and validation
- Basic transaction flows
What May Not Work on Testnets
- Cross-chain asset transfers via bridges
- Multi-chain swap routes
- Complex DeFi operations requiring solver infrastructure
Recommended Testing Approach
For comprehensive testing of multichain features, consider:
- Use testnets for single-chain logic — Test your transaction building, batching, and account setup
- Use mainnets with small amounts for multichain — When testing cross-chain flows, use production with minimal funds
- Leverage simulation — Use the quote and simulation endpoints to validate transactions before execution
// Example: Get a quote to simulate without executing
const quote = await meeClient.getQuote({
instructions: [...],
feeToken: {
address: "0x...",
chainId: baseSepolia.id
}
});
// Inspect the quote before executing
console.log("Estimated gas:", quote.paymentInfo);
console.log("User operations:", quote.userOps);
Next Steps
