Renato Barboza da Costa 👋

Smart Contract Security Researcher focused on EVM ecosystems, with 5+ years of fullstack engineering behind me. I'm currently transitioning into web3 security — auditing Solidity contracts, reproducing historical exploits in Foundry, and participating in public audit contests (Code4rena, Sherlock, Cantina). My fullstack background is a differentiator: I understand the full stack of modern web3 applications — frontend, backend, smart contracts, and the integration points between them. That's where a lot of real-world vulnerabilities live and where auditors with only Solidity background tend to miss. What I'm working on right now: - Analyzing recent DeFi exploits and writing breakdowns - Building a public portfolio of Foundry PoCs - Submitting findings in public audit contests - Deep diving into EVM internals and common vulnerability patterns Day job: Senior Fullstack Developer at BossaBox (React, TypeScript, Node.js). 5+ years delivering production applications for web and mobile (iOS/Android), with experience across fintech, banking, and trading platforms. Reach out if you're working on: → Smart contract audits or security reviews (independent engagements) → Bug bounty programs on DeFi protocols → Web3 security research collaborations HackerOne: hackerone.com/0xren_ GitHub: github.com/Remato X/Twitter: x.com/_0xRen