When I first started diving into the world of Web3 during a development course, I stumbled upon the concept of reentrancy. It was one of those moments where curiosity took over — I couldn’t believe how a small oversight in a smart contract’s code could lead to such catastrophic outcomes. This vulnerability quickly became my gateway into exploring the broader realm of blockchain security. Reentrancy attacks taught me just how crucial it is to build secure smart contracts, especially when dealing with users’ funds. Today, I’m excited to share insights on the four types of reentrancy vulnerabilities and how we can safeguard our code against them.

Smart contracts written in Solidity for the Ethereum blockchain, are transforming how decentralized applications (dApps) operate. But with the power to manage assets and execute complex interactions comes the critical need to ensure the contract’s logic is secure. One of the most important areas to focus on is business logic vulnerabilities — flaws in how the contract’s functions and processes are designed.

If you’re just starting out in the world of blockchain security, auditing smart contracts can feel pretty overwhelming. Believe me, I know what it’s like to dive into an audit, feeling the pressure of finding issues. Over time, I’ve developed a plan that makes tackling audits much more manageable. In this guide, I’ll share the exact process I use — from reading the documentation to identifying core contracts and focusing on high-risk areas. Let’s dive in and navigate this together.