Ethereum Development Tutorial 2026

Build your first decentralized application from scratch

Prerequisites

Node.js 18+ installed
Basic JavaScript/TypeScript knowledge
An Ethereum wallet (MetaMask)
API key from Alchemy or Infura

Step-by-Step Guide

Set Up Your Project
Create a new directory and initialize npm:

mkdir my-eth-dapp
cd my-eth-dapp
npm init -y
npm install viem ethers

Connect to Ethereum
Using viem (recommended for 2026):

import { createPublicClient, http } from 'viem'
import { mainnet } from 'viem/chains'

const client = createPublicClient({
  chain: mainnet,
  transport: http('https://eth-mainnet.g.alchemy.com/v2/YOUR_KEY')
})

Read Blockchain Data
Query account balances:

const balance = await client.getBalance({
  address: '0x...'
})
console.log(balance)

Send Transactions
Transfer ETH:

const hash = await client.sendTransaction({
  to: '0x...',
  value: parseEther('0.01')
})

Read Smart Contract Data
Query ERC-20 balances:

const readContract = await client.readContract({
  address: '0x...', // token address
  abi: [...],
  functionName: 'balanceOf',
  args: ['0x...']
})

Popular Libraries in 2026

viem - Modern, lightweight, TypeScript-first
ethers - Mature, widely used, great documentation
web3.js - Legacy library, large community

💡 Best Practice: Use viem for new projects. It's faster, smaller, and designed for modern Ethereum development.

Next Steps

Learn wagmi for React integration
Explore DeFi protocols
Build an NFT marketplace with NFT APIs

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