Universal Accounts with EIP-7702

A developer demo showcasing EIP-7702 mode with Particle Network's Universal Accounts and Privy authentication.

What This Demo Shows

EIP-7702 lets an EOA act directly as a Universal Account—no separate contract deployment or asset transfers required. Your existing wallet address gains Universal Account features instantly.

Features demonstrated:

• Unified balance view across EVM chains + Solana
• Swap/bridge tokens to any supported chain via LI.FI for token discovery and Universal Account infrastructure for liquidity orchestration
• Withdraw USDC to external addresses
• Social login with Privy (email, Google, Twitter)

Quick Start

1. Clone and Install

git clone https://github.com/soos3d/universal-accounts-7702
yarn install

2. Configure Environment

Copy .env.example to .env and add your credentials:

# Particle Network - https://dashboard.particle.network
NEXT_PUBLIC_PROJECT_ID="your-particle-project-id"
NEXT_PUBLIC_CLIENT_KEY="your-particle-client-key"
NEXT_PUBLIC_APP_ID="your-particle-app-id"

# Privy - https://dashboard.privy.io
NEXT_PUBLIC_PRIVY_APP_ID="your-privy-app-id"
NEXT_PUBLIC_PRIVY_CLIENT_ID="your-privy-client-id"

3. Run

yarn dev

Open http://localhost:3000

Available Scripts

Command	Description
yarn dev	Start development server
yarn build	Production build
yarn start	Start production server
yarn lint	Run ESLint

How EIP-7702 Mode Works

Traditional Smart Accounts:
EOA (0xABC...) → Deploy Smart Account (0xDEF...) → Transfer assets → Use features

EIP-7702 Mode:
EOA (0xABC...) → Sign authorization → EOA becomes Universal Account

Key difference: Same address, no transfers, zero friction.

1. Initialize Universal Account

const ua = new UniversalAccount({
  projectId: process.env.NEXT_PUBLIC_PROJECT_ID!,
  projectClientKey: process.env.NEXT_PUBLIC_CLIENT_KEY!,
  projectAppUuid: process.env.NEXT_PUBLIC_APP_ID!,
  smartAccountOptions: {
    useEIP7702: true,  // Enable 7702 mode
    ownerAddress: wallet.address,
  },
});

2. Create a Transaction

const transaction = await ua.createUniversalTransaction({
  chainId: CHAIN_ID.BASE_MAINNET,
  expectTokens: [{ tokenAddress: USDC_ADDRESS, amount: "10" }],
  transactions: [{ to: recipient, data: "0x", value: "0" }],
});

3. Handle EIP-7702 Authorization

On first transaction per chain, the SDK returns userOps that need 7702 authorization. This demo uses Privy's useSign7702Authorization hook:

// Check each userOp for required authorization
for (const userOp of transaction.userOps) {
  if (userOp.eip7702Auth && !userOp.eip7702Delegated) {
    // Sign with Privy's hook
    const auth = await signAuthorization({
      contractAddress: userOp.eip7702Auth.address,
      chainId: userOp.eip7702Auth.chainId,
      nonce: userOp.eip7702Auth.nonce,
    });

    // Serialize signature for SDK
    const sig = Signature.from({ r: auth.r, s: auth.s, yParity: auth.yParity });
    authorizations.push({
      userOpHash: userOp.userOpHash,
      signature: sig.serialized,
    });
  }
}

4. Sign and Send

// Sign the transaction root hash
const { signature } = await signMessage({ message: transaction.rootHash });

// Send with authorizations
const result = await ua.sendTransaction(transaction, signature, authorizations);

Key Points

• First tx per chain: Requires EIP-7702 authorization signature
• Subsequent txs: No re-authorization needed (eip7702Delegated will be true)
• Signature format: Privy returns r, s, yParity; SDK expects serialized hex via ethers.Signature

See lib/eip7702.ts for the full implementation.

Supported Chains

Chains supporting 7702: Ethereum, Arbitrum, Base, Optimism, Polygon, BNB Chain, Sonic, Berachain

Learn More

• Universal Accounts Docs
• EIP-7702 Specification
• Privy Docs
• LI.FI Docs

License

MIT