Smart Wallets represent a significant evolution in blockchain technology, leveraging the ERC-4337 standard for account abstraction. These wallets function as smart contract accounts rather than traditional externally owned accounts (EOAs), enabling advanced features like gas sponsorship and batch transactions without requiring users to manage private keys in the conventional way.
What Is a Smart Wallet?
A Smart Wallet is an ERC-4337 compatible account abstraction wallet that operates as a single address across multiple Ethereum Virtual Machine (EVM) networks. Currently, support is limited to Base Mainnet and Base Sepolia, but future network integrations will automatically extend to existing Smart Wallets without address changes.
Each Smart Wallet has a single owner—an account backed by a private key that authorizes transactions. Think of this private key as the master password controlling the wallet's operations.
Key Features and Benefits
- Cross-Network Address Consistency: Your Smart Wallet address remains the same across all supported EVM networks.
- Gas Sponsorship: Utilize paymaster services to cover transaction fees, enhancing user experience.
- Batch Transactions: Execute multiple operations in a single transaction, reducing costs and complexity.
- Enhanced Security: Leverage smart contract capabilities for improved security models.
How to Create a Smart Wallet
We recommend using Viem, a widely adopted library, to generate the private key and owner account for your Smart Wallet.
import { generatePrivateKey, privateKeyToAccount } from "viem/accounts";
import { createSmartWallet } from "@coinbase/coinbase-sdk";
const privateKey = generatePrivateKey();
const owner = privateKeyToAccount(privateKey);
const smartWallet = await createSmartWallet({
signer: owner
});
const smartWalletAddress = smartWallet.address;Remember: The private key must be stored securely and persisted across sessions. Never expose this key in client-side code or unsecured environments.
Sending User Operations
UserOperations are the mechanism through which Smart Wallets execute transactions. This approach enables batch processing and gas sponsorship without traditional EOA limitations.
The sendUserOperation method supports both single and batch transactions, along with paymaster integration for gas sponsorship.
Example: Batch Transaction
const smartWallet = await createSmartWallet({
signer: owner
});
const userOperation = await smartWallet.sendUserOperation({
calls: [
{
to: "0x1234567890123456789012345678901234567890",
value: parseEther("0.0000005"),
data: "0x",
},
{
to: "0xb720E683CB90838F23F66a37Adb26c24e04D1b60",
abi: ABI,
functionName: "someFunction",
args: [123n, true, "0x3234567890123456789012345678901234567890"],
},
],
chainId: 84532,
});
const userOperationResult = await waitForUserOperation(userOperation);Note: When using ABIs, include as const for proper TypeScript compilation and type safety.
Understanding Paymaster Integration
Paymaster services handle gas sponsorship for your Smart Wallet transactions. On Base Sepolia, the CDP API automatically sponsors gas, meaning you can send UserOperations without holding any gas tokens. For Base Mainnet, you'll need to provide a Paymaster URL to enable gas sponsorship.
👉 Explore advanced gas sponsorship solutions
Security Best Practices
Securing your Smart Wallet requires careful attention to private key management. As a developer, you're responsible for implementing robust security measures.
Secure Storage Methods
- Encrypted Databases: Store private keys in encrypted form within secure database systems
- Hardware Security Modules: Use HSMs for enterprise-grade key protection
- Environment Variables: Secure development environments with proper access controls
Local Persistence Example
For development purposes, you might store private keys locally with encryption:
// Example of secure local storage implementation
import { encryptData, decryptData } from './security-utils';
const encryptedKey = encryptData(privateKey, encryptionPassword);
localStorage.setItem('encryptedPrivateKey', encryptedKey);Always encrypt private keys before storage, even in local environments.
Reinstantiating Smart Wallets
When starting new sessions, you'll need both the private key and Smart Wallet address to recreate the wallet instance:
import { privateKeyToAccount } from "viem/accounts";
import { createSmartWallet } from "@coinbase/coinbase-sdk";
const retrievedPrivateKey = decryptData(encryptedKey, encryptionPassword);
const owner = privateKeyToAccount(retrievedPrivateKey);
const smartWallet = await createSmartWallet({
signer: owner
});Frequently Asked Questions
What makes Smart Wallets different from traditional crypto wallets?
Smart Wallets use account abstraction through ERC-4337, allowing them to function as smart contracts rather than externally owned accounts. This enables features like batch transactions, gas sponsorship, and enhanced security models that aren't possible with traditional wallets.
How do I ensure my Smart Wallet remains secure?
Implement robust private key storage solutions including encryption, secure backend storage, and proper access controls. Never store private keys in plaintext or expose them to client-side applications. Regularly audit your security practices and consider using professional security services.
Can I use the same Smart Wallet across different blockchains?
Yes, Smart Wallets maintain the same address across all supported EVM networks. Currently, only Base Mainnet and Base Sepolia are supported, but additional networks will be added in the future without requiring address changes.
What happens if I lose my private key?
Unlike traditional wallets, Smart Wallets may offer recovery options through social recovery or multi-signature arrangements, though implementation details depend on your specific setup. Always maintain secure backups of your private keys.
How does gas sponsorship work with Smart Wallets?
Paymaster services can sponsor transaction costs, allowing users to interact with dApps without holding native tokens for gas fees. On testnets like Base Sepolia, this sponsorship is often automatic, while mainnet implementations require configuring paymaster services.
Are there any limitations to batch transactions?
While batch transactions offer significant efficiency improvements, they're subject to blockchain gas limits and smart contract constraints. Always test your transactions thoroughly and ensure your batch operations remain within reasonable complexity limits.
Smart Wallets represent the future of blockchain interaction, combining enhanced usability with powerful new capabilities. As the technology evolves, we can expect even more innovative features and broader network support.