Web3 Frontend Skill Skill

Web3 Frontend Skill

Master Web3 frontend development with wallet integration, modern libraries (viem/wagmi), and production dApp patterns.

Quick Start

# Invoke this skill for Web3 frontend development
Skill("web3-frontend", topic="wallet", framework="react")

Topics Covered

1. Wallet Integration

Connect users to Web3:

RainbowKit: Beautiful wallet modal
WalletConnect: Mobile support
Account Abstraction: ERC-4337
Multi-chain: Network switching

2. Transaction Management

Handle blockchain interactions:

Write Operations: Contract writes
State Tracking: Pending, confirmed
Gas Estimation: Fee display
Error Handling: User-friendly messages

3. Signing & Auth

Verify user identity:

EIP-712: Typed data signing
SIWE: Sign-In with Ethereum
Permit: Gasless approvals
Message Signing: Personal sign

4. React Hooks

Modern patterns with wagmi:

useAccount: Connection state
useWriteContract: Transactions
useReadContract: Data fetching
useWaitForTransactionReceipt: Confirmations

Code Examples

Connect Wallet

'use client';

import { ConnectButton } from '@rainbow-me/rainbowkit';
import { useAccount } from 'wagmi';

export function WalletConnect() {
  const { address, isConnected } = useAccount();

  return (
    <div>
      <ConnectButton />
      {isConnected && <p>Connected: {address}</p>}
    </div>
  );
}

Write Contract

import { useWriteContract, useWaitForTransactionReceipt } from 'wagmi';
import { parseEther } from 'viem';

export function MintButton() {
  const { writeContract, data: hash, isPending } = useWriteContract();
  const { isLoading, isSuccess } = useWaitForTransactionReceipt({ hash });

  const mint = () => {
    writeContract({
      address: '0x...',
      abi: [...],
      functionName: 'mint',
      args: [1n],
      value: parseEther('0.08'),
    });
  };

  return (
    <button onClick={mint} disabled={isPending || isLoading}>
      {isPending ? 'Confirm in wallet...' :
       isLoading ? 'Minting...' :
       isSuccess ? 'Minted!' : 'Mint NFT'}
    </button>
  );
}

Sign Typed Data (EIP-712)

import { useSignTypedData } from 'wagmi';

const DOMAIN = {
  name: 'My App',
  version: '1',
  chainId: 1,
  verifyingContract: '0x...',
};

export function useSignOrder() {
  const { signTypedDataAsync } = useSignTypedData();

  const sign = async (order: Order) => {
    return await signTypedDataAsync({
      domain: DOMAIN,
      types: { Order: [...] },
      primaryType: 'Order',
      message: order,
    });
  };

  return { sign };
}

Error Handling

export function parseError(error: unknown): string {
  const msg = error instanceof Error ? error.message : String(error);

  if (msg.includes('user rejected')) return 'Transaction cancelled';
  if (msg.includes('insufficient funds')) return 'Insufficient balance';
  if (msg.includes('execution reverted')) {
    const reason = msg.match(/reason="([^"]+)"/)?.[1];
    return reason || 'Transaction would fail';
  }

  return 'Transaction failed';
}

Package Setup

npm install wagmi viem @rainbow-me/rainbowkit @tanstack/react-query

// providers/Web3.tsx
import { WagmiProvider } from 'wagmi';
import { RainbowKitProvider } from '@rainbow-me/rainbowkit';
import { QueryClientProvider, QueryClient } from '@tanstack/react-query';
import { config } from './config';

const queryClient = new QueryClient();

export function Web3Provider({ children }) {
  return (
    <WagmiProvider config={config}>
      <QueryClientProvider client={queryClient}>
        <RainbowKitProvider>{children}</RainbowKitProvider>
      </QueryClientProvider>
    </WagmiProvider>
  );
}

Common Patterns

| Pattern | Use Case | Hook | |---------|----------|------| | Connect wallet | User auth | useAccount | | Read data | Display balances | useReadContract | | Write tx | Mint, transfer | useWriteContract | | Wait for tx | Confirm state | useWaitForTransactionReceipt | | Sign message | Auth, permit | useSignMessage |

Common Pitfalls

| Pitfall | Issue | Solution | |---------|-------|----------| | Hydration error | SSR mismatch | Use dynamic with ssr: false | | BigInt serialization | JSON.stringify | Custom serializer | | Stale data | Cache issues | Use refetchInterval |

Troubleshooting

"Wallet not connecting"

// Ensure client-side only
import dynamic from 'next/dynamic';

const ConnectButton = dynamic(
  () => import('./ConnectButton'),
  { ssr: false }
);

"Transaction pending forever"

Check gas settings or speed up:

await wallet.sendTransaction({
  ...tx,
  maxFeePerGas: tx.maxFeePerGas * 120n / 100n,
});

Security Checklist

[ ] Never expose private keys
[ ] Validate contract addresses
[ ] Sanitize user inputs
[ ] Use proper error boundaries
[ ] Implement CSP headers

Cross-References

Bonded Agent: 05-web3-frontend
Related Skills: ethereum-development, solidity-development

Version History

| Version | Date | Changes | |---------|------|---------| | 2.0.0 | 2025-01 | Production-grade with wagmi v2, viem | | 1.0.0 | 2024-12 | Initial release |

Agent Skills: Web3 Frontend Skill

Skill Files