RareSkills Web3
Blockchain Instructors

Jeffrey is the instructor of the only two expert-level Ethereum development courses on Udemy, both of which are bestsellers. His blog on Ethereum development has significantly influenced major projects in the web3 space.
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While working at Yahoo, Jeffrey became the youngest Senior Engineering Manager at the company, building the video machine learning platforms and team from the ground up. He has consulted for dozens of companies, including the National Football League (NFL) in America.
He holds two patents in machine learning and has placed in the top 10 in highly competitive international machine learning contests.
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Jeffrey is the founder of 8020cto.com, a leading technical startup advisory firm in Southeast Asia consisting of expert engineering leaders from companies like Uber, Instagram, Coinbase, Apple, and others. 8020cto also provides technical due diligence for Venture Capital firms, some of which have over half a billion dollars in management.

He has a passion for learning and teaching that stretches all the way back to high school when he mentored college students in calculus. At Columbia University, he was recognized as a top teaching assistant in the computer science department and was awarded a scholarship for it.

RareSkills is now his way to share his passion for rigorous learning and subject mastery with other software engineers.

Gonçalo Magalhães (gmhacker) is an aerospace engineer working as a smart contract security researcher. In the past he has worked for various companies spanning different industries: IoT, embedded systems, finances and digital TV. After transitioning to the Web3 industry, he worked as a smart contract developer for different entities and taught blockchain technologies in companies and bootcamps. He was awarded the Immunefi Whitehat Hacker Scholarship, eventually leading him to working as a smart contract triager at Immunefi. He's now the Head of Security at Immunefi.

Shung is a Smart Contract Auditor at Kebasec and an Associate Security Researcher at Spearbit, renowned for his expertise in blockchain security. His previous experience as a protocol developer at Pangolin has endowed him with a deep understanding of decentralized financial platforms. Shung’s keen eye for detail and security acumen led him to discover a critical vulnerability in Uniswap X, which earned him a substantial $200k bounty. This accomplishment is paralleled by his quick actions that averted a potential $30 million hack on the Hedera protocol by addressing a precompile exploit. His impressive portfolio includes Solady ERC721, Seaport, Trader Joe, Manifold Finance, and Poolsharks.

Madigan (Zigtur) is ranked #1 on the all time earnings leaderboard (with over 622k earned) at Cantina, a competitive smart contract auditing platform by Spearbit. Previously, he was a smart contract auditor and web2 security engineer at Quarkslab. He is an alumni of RareSkills.

João Paulo Morais holds a PhD in physics and has published over 30 academic articles in international journals, co-supervising master's students in black hole physics. He began programming in Pascal and Clipper at a young age and built his first websites when tables were still used for page layouts—well before CSS, which somewhat reveals his experience (and his age). In 2021, he transitioned to Web3, blockchain, and cryptography during the rise and fall of NFT games, and has since focused on studying, writing, and lecturing about Ethereum and zero-knowledge proofs. He also teaches a comprehensive Solidity course on Udemy (in Portuguese) and has authored an in-depth Solidity course on Medium, along with several advanced Solidity articles for RareSkills.

Daniel Cumming studied at The University of Queensland completing his Bachelor of Arts, and is completing his Masters of Information Technology. Between 2020 and 2022 he worked for The University of Queensland as a research and teaching assistant as a member of the Program Analysis Centre. He assisted teaching formal methods, computer systems, and algorithms. Daniel worked on research projects related to specifying the ARM64 instruction set, invariant generation techniques, and automatic verification of EVM bytecode smart contracts with Vale.
At Runtime Verification Inc., Daniel has completed multiple audits for smart contracts and infrastructure on Rust based blockchains. He is currently a researcher for the KMIR project, which aims to encode the operational semantics of Rust's stable MIR in the K Framework.

Philippe Dumonet is an experienced smart contract developer and auditor with over three years of experience. He has worked for various companies and decentralized autonomous organizations (DAOs) and is currently a co-founder of DeReg.io, a startup that develops solutions to improve the security of DeFi protocols. Philippe started his software development journey at a young age and has won multiple crypto hackathons. He became the youngest Senior Smart Contract Auditor at Quantstamp at the age of 19. Philippe is dedicated to his side projects and his own startup, while also engaging in security research and optimizing popular contracts, such as ERC721H and METH.