Learn SOLIDITY with Real Code Examples
Updated Nov 19, 2025
Practical Examples
Create ERC-20 token
Deploy NFT contract
Build a decentralized marketplace
Create DAO governance contract
Develop DeFi staking protocol
Troubleshooting
Check for reentrancy vulnerabilities
Verify require conditions
Ensure correct visibility specifiers
Check gas usage & optimize loops
Study transaction traces for failed calls
Testing Guide
Write unit tests using Hardhat/Foundry
Test edge cases & error paths
Simulate multi-account interactions
Test reentrancy & exploit conditions
Run gas reports
Deployment Options
Ethereum mainnet
Ethereum testnets (Sepolia, Holesky)
Layer 2 rollups (Arbitrum, Optimism, Base)
Sidechains (Polygon)
Private EVM chains
Tools Ecosystem
Hardhat
Foundry
Truffle
OpenZeppelin Contracts
Remix IDE
Integrations
Web3.js & Ethers.js
IPFS & Filecoin
The Graph indexing
Chainlink oracles
Layer-2 networks
Productivity Tips
Use Hardhat tasks
Automate tests
Use OpenZeppelin templates
Rely on security checkers
Reuse battle-tested libraries
Challenges
Create ERC-20 token
Build NFT smart contract
Create DAO voting mechanism
Make yield farming rewards contract
Build full DeFi protocol component