How to Set Up a Web3 Login Without Crying (Too Much)

So, you've decided to dip your toes into the wild world of web3. You want that slick "Connect Wallet" button on your site because, let's be honest, it looks cool and makes you seem like you're living in the year 3000. The good news is that you don't need to understand the intricate details of elliptic curve cryptography or write your own smart contracts from scratch. The bad news is that you'll still have to deal with JavaScript dependencies, which is its own special kind of nightmare.

First things first, you're not building this from the ground up. Don't be a hero. We're going to use a library to do the heavy lifting. For a React site, something like wagmi paired with RainbowKit or ConnectKit is the way to go. They give you the UI components, the wallet connection logic, and all the hooks you need to actually do stuff. Your first step is to install them. Open your terminal and prepare to sacrifice some disk space to the node_modules gods:

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

Next, you'll need to wrap your application in their provider components. This is the classic React context provider pattern you've seen a million times. Find your main _app.js or index.tsx file and smother it with providers. It'll look something like this. You'll also need to get a projectId from WalletConnect Cloud, because of course you need to sign up for something. Don't worry, it's free. For now.

import '@rainbow-me/rainbowkit/styles.css';
import { getDefaultConfig, RainbowKitProvider } from '@rainbow-me/rainbowkit';
import { WagmiProvider } from 'wagmi';
import { mainnet, polygon, optimism, arbitrum, base } from 'wagmi/chains';
import { QueryClientProvider, QueryClient } from "@tanstack/react-query";

const config = getDefaultConfig({
  appName: 'My Super Cool Web3 Site',
  projectId: 'YOUR_WALLETCONNECT_PROJECT_ID',
  chains: [mainnet, polygon, optimism, arbitrum, base],
});

const queryClient = new QueryClient();

const App = ({ Component, pageProps }) => {
  return (
    <WagmiProvider config={config}>
      <QueryClientProvider client={queryClient}>
        <RainbowKitProvider>
          <Component {...pageProps} />
        </RainbowKitProvider>
      </QueryClientProvider>
    </WagmiProvider>
  );
};

With that boilerplate out of the way, you can finally add the button. Go to your header or navigation component and import the ConnectButton from RainbowKit. Plop it in there, and boom, you have a login button. It's almost suspiciously easy.

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

export const Header = () => {
  return (
    <nav>
      {/* Your other nav links */}
      <ConnectButton />
    </nav>
  );
};

Now what? Well, a user can connect their wallet. You can use the useAccount hook from wagmi to get their address and see if they're connected. You can display their address, show them a special message, or just bask in the glory of knowing you've successfully authenticated someone without a single email or password field. You've done it. You're a web3 developer. Now you just have to figure out what to do with it.