Testing
Web3 wallet integration is where most dApp user experience problems live. The smart contracts can be flawless, but if MetaMask's popup doesn't appear, the wrong network is connected, or a transaction confirmation hangs indefinitely, users abandon the app. Testing wallet integrations requires a different approach from
Testing
Smart contract bugs are permanent. Once deployed, a vulnerability in your Solidity code can drain millions of dollars with no recourse. Testing is not optional — it is the only line of defense before deployment. Two tools dominate the space: Hardhat, which brings JavaScript/TypeScript familiarity, and Foundry, which keeps everything
Testing
NFT smart contracts look simple until they're not. An ERC-721 with a public mint function, a royalty mechanism, and an allowlist touches access control, financial logic, and third-party standards simultaneously. A bug in the royalty calculation means artists lose revenue on every secondary sale. An allowlist
Testing
DeFi protocols operate in an adversarial environment. Every deployed contract is visible to attackers who can manipulate prices, front-run transactions, and chain multiple protocol interactions into a single atomic exploit. Testing in isolation on a blank local chain misses all of this. The only way to test DeFi protocols
Testing
Blockchain transactions are not like HTTP requests. They have lifecycle states — pending, confirmed, failed — that exist asynchronously across potentially minutes. They can be reorganized out of the canonical chain. They emit event logs that serve as the primary data source for off-chain systems. A testing strategy that treats a
Testing
For years, JavaScript was the only option for Solidity testing. Hardhat and Truffle gave you a familiar environment, but context-switching between Solidity contracts and JavaScript test files created friction. You had to constantly think about type conversions, BigNumber handling, and the impedance mismatch between the two languages. Foundry changes
Testing
Hardhat is the most widely used Ethereum development framework in the JavaScript ecosystem. Its TypeScript support, rich plugin library, and integration with ethers.js make it the default choice for teams building full-stack DApps. This tutorial covers everything from project setup to advanced patterns like mainnet forking and gas
Testing
Integration testing for Web3 applications verifies that your application code correctly interacts with smart contracts under realistic conditions. Using ethers.js with a local Hardhat node gives you fast, deterministic tests with full control over blockchain state. Mainnet forking adds real protocol state when you need to test against live
Testing
Smart contract bugs are permanent — once deployed, there is no hotfix. Rigorous testing with unit tests, integration tests, and fuzz testing is the only way to catch vulnerabilities before they cost real money. Hardhat and Foundry are the two dominant testing frameworks, each with distinct strengths. This guide covers both,
Testing
Security testing for smart contracts requires both automated tools and manual review. Slither performs fast static analysis and catches a wide range of common vulnerabilities. Mythril uses symbolic execution to find logical flaws that static analysis misses. Echidna performs property-based fuzzing to verify that invariants hold under adversarial conditions.
Testing
DeFi protocols operate in an adversarial environment where attackers use flash loans, oracle manipulation, and sandwich attacks to drain value. Testing must simulate these attacks explicitly. Mainnet forking provides realistic state, Foundry's invariant tester verifies that core mathematical properties hold across arbitrary transaction sequences, and explicit attack simulations