Smart Contract Testing with Hardhat 3 and Ethers v6
Testing Solidity contracts with Hardhat 3, ethers v6 and Mocha: fixtures, time travel, custom errors, fuzzing, coverage, gas stats, mainnet forking and CI.
Category: Web3
Posts
Solana Program Development with Rust and Anchor 1.x
Solana program development with Rust and Anchor 1.x: accounts, PDAs, constraints, tests, security, and where Proof of History stands after Alpenglow.
Web3 Wallet Integration: EIP-6963, Ethers v6 and Reown
Web3 wallet integration today: EIP-6963 wallet discovery, ethers v6 BrowserProvider, chain switching, Reown AppKit for mobile, Sign-In with Ethereum.
Polygon PoS Architecture and Layer 2 Scaling Explained
How Polygon PoS works: Bor, Heimdall v2, checkpoints, POL and ~5-second finality. How it differs from rollups, the zkEVM shutdown, and notes for developers.
Ethereum with web3.py v7: Providers, Transactions, Events
Talking to Ethereum with web3.py v7: HTTP, async and WebSocket providers, signing EIP-1559 transactions, reading ERC-20s, chunked event logs and PoA chains.
Flash Loan Arbitrage Bot: Lessons From My Python Prototype
DEX arbitrage with Aave V3 flash loans: what my Python bot did and didn't do, a Solidity contract that enforces profit on-chain, and mainnet fork tests.
How a DEX Aggregator Works: Quotes, Routing, Contracts
The parts of a DEX aggregator: Uniswap V2/V3 quotes with ethers v6, gas-adjusted comparison, split routing, a safe swap contract and MEV protection.
Solidity Security and Gas Optimization: A Practical Guide
Reentrancy, access control, proxy pitfalls, oracle manipulation and gas optimization in Solidity 0.8 with OpenZeppelin 5, plus Foundry tests and a checklist.
Blockchain Data Analysis in Python: Indexer, The Graph, Dune
On-chain data with Python: event subscriptions in web3.py, a small SQLAlchemy 2 indexer, The Graph and Dune APIs, and Telegram alerts for large transfers.
NFT Minting on Ethereum: ERC721A, Merkle Allowlist, Tests
An allowlist NFT contract with ERC721A and OpenZeppelin 5: Merkle proofs, IPFS metadata, Foundry tests, an ethers v6 mint button and a Sepolia deploy.
