How to Build a Web3 Application — From Smart Contract to Production dApp

Web3 Application Architecture

Layer 1 — Smart contracts: On-chain business logic. Written in Solidity (EVM) or Rust (Solana). Immutable execution on the blockchain.

Layer 2 — Blockchain indexer (The Graph): Converts on-chain event data into queryable GraphQL API. Makes complex on-chain queries (user history, aggregates, rankings) practical.

Layer 3 — Front-end (React/Next.js): Reads blockchain state via The Graph. Interacts with contracts via wagmi/viem. Connects wallets via WalletConnect.

Layer 4 — Supporting services: Authentication (SIWE), notifications (off-chain), analytics (Dune, Footprint), monitoring (Tenderly).

Development Steps

Step 1: Define the on-chain and off-chain boundary. What must be on-chain (ownership, settlement, governance)? What should be off-chain (analytics, notifications, UX state)?

Step 2: Write smart contracts. Following the specification → development → test → audit process.

Step 3: Deploy The Graph subgraph. Define entities (User, Transaction, Position) and event handlers. Deploy to The Graph Network or a hosted node.

Step 4: Build the React front-end. Install wagmi, viem, WalletConnect v2. Set up providers and chain configuration. Build components that read from The Graph via GraphQL and write to contracts via wagmi hooks.

Step 5: Add wallet integration. WalletConnect for hardware and mobile wallets. Social login wallet for mainstream users (Magic Link, Privy).

Step 6: Deploy and monitor. Deploy contracts to mainnet. Deploy front-end to Vercel. Set up Tenderly monitoring for contract events.

The Web3 Tech Stack