Blockchain Security Engineer

Joseph
Oluwadara

Security Engineer at Coinbase, securing Base L2 infrastructure. Independent researcher with 50+ Critical / High / Medium findings across 200,000+ SLOC on Code4rena, Cantina, Sherlock & Immunefi. Deep expertise in EVM internals, cross-chain bridges, and Solana programs.

jsatimehin@gmail.com josephdara Resume @jhoe0x
50+
Critical / High / Med Findings
200k+
Lines of Code Reviewed
20+
Competitive Audits
01

Experience

Blockchain Security Engineer
Coinbase
  • Audited the Base-Solana Bridge for cross-chain asset transfer security.
  • Led security review of x402, Coinbase's HTTP-native payment protocol on Base.
  • Led security review and validation of the Base Azul major L2 upgrade.
  • Built internal AI-powered smart contract auditing tooling.
  • On-call incident response rotation — triaged and coordinated live security incidents.
  • Conducted 20+ ecosystem security reviews for projects building on Base.
  • Speaker at DeFi Security Summit 2025.
Nov 2024 – Present
Solo Smart Contract Security Researcher
Code4rena · Cantina · Immunefi · Sherlock · Codehawks
  • Conducted 20+ competitive audits, uncovering 40+ High/Medium severity bugs.
  • Reviewed 200,000+ SLOC across AMMs, lending markets, stablecoins, and omnichain infra.
  • Top 5 finish in the Ethena contest — stablecoin protocol with $1B+ TVL.
  • Completed Ethernaut, Damn Vulnerable DeFi, and Secureum Bootcamp CTFs.
Jan 2023 – Jan 2025
Developer Advocate (Contract)
INTMAX
  • Led ZK protocol education and developer onboarding across Africa — Google DevFest Lagos, Africa Tech Summit Nairobi.
Oct 2023 – Mar 2024
Blockchain Developer (Contract)
Astra Metaverse · Collect Waves
  • Developed and deployed ERC-1155 contracts for the Astra Metaverse Marketplace with backend API integrations.
  • Built Music NFT and marketplace contracts with ERC-20 tokens and API integrations at Collect Waves.
May 2022 – Jan 2023
02

Audit Achievements

Audit
Base-Solana Bridge
Cross-chain bridge security · Coinbase
Audit
x402 Protocol
HTTP-native payments on Base · Coinbase
Speaker
DeFi Security Summit 2025
Representing Coinbase Security team
20+
Ecosystem Security Reviews
Base project reviews + M&A technical audits · Coinbase
Top 5 / 9
Multiple Top Finishes
Ethena (Top 5), WildCat (Top 9), Good Entry (Top 9) · Code4rena
03

Technical Skills

Languages
Solidity Assembly (YUL) Rust JavaScript TypeScript Python
Frameworks & Tools
Foundry Hardhat Anchor Slither Aderyn Echidna
Protocol Experience
AMMs Lending Vaults Proxies Liquid Staking L2 / Bridge Smart Wallets
Audit Platforms
Code4rena Cantina Sherlock Immunefi QuillAudits
Web2 Development
Node.js React Next.js Express.js NestJS REST APIs GraphQL PostgreSQL MongoDB