Yoichi Hirai
Member Of Technical Staff at Nexus
Portugal
Summary
🤩
Rockstar🎓
Top SchoolYoichi Hirai is a Member of Technical Staff based in Portugal with 13 years of experience building secure, production-grade blockchain and systems software. His background spans formal verification, compiler and smart-contract engineering—contributions include improvements to Solidity and automation work on Ethereum's canonical Yellow Paper—demonstrating a blend of rigorous correctness work and practical DevOps. He has fixed critical memory and dependency issues in the Aleth Ethereum client, hardened DAO contract logic, and improved onboarding docs for Raiden, showing attention to both low-level reliability and developer experience. A former formal verification engineer at Ethereum and FireEye and a senior engineer at BedRock Systems, he moves comfortably between research-grade proofs and hands-on engineering. Since 2025 he’s been active under Flamingo Ponderado Unipessoal LDA on GitHub, reflecting ongoing entrepreneurial and open-source engagement. Colleagues describe him succinctly as a “convenience logician”—someone who makes complex systems easier to reason about.
12 years of coding experience
10 years of employment as a software developer
University of Tokyo
English, Japanese, German, Portuguese
Github Skills (26)
debug10
c-language10
solidity10
compiler-development10
technical-writing10
memory-management10
bash10
cicd10
security10
automation10
ethereum10
build-automation10
blockchain10
smart-contracts10
automations10
Programming languages (19)
Github contributions (5)
ethereum/yellowpaper
Sep 2016 - Jun 2021
The "Yellow Paper": Ethereum's formal specification
Role in this project:
DevOps Engineer & Automation Engineer
DevOps Engineer & Automation EngineerContributions:360 commits, 331 PRs, 184 pushes in 4 years 9 months
Contributions summary:Yoichi primarily focused on automating the build process for the Ethereum Yellow Paper. They modified `build.sh` to include versioning and conditional compilation based on command-line arguments. The user also updated the `travis_deploy.sh` script to generate the PDF and deploy it, with changes related to file paths and version information. They also implemented a check for merge conflicts within the build script.
ethereumformal-specificationspecificationyellowformal
raiden-network/raiden
Nov 2018 - Oct 2019
Raiden Network
Role in this project:Technical Writer
Technical WriterContributions:1 release, 278 commits, 148 PRs in 11 months
Contributions summary:Yoichi primarily focused on improving the documentation of the Raiden Network project, specifically the Raiden Developer Onboarding Guide. Their contributions involved fixing grammar, spelling, and other editorial improvements to the documentation, aiming to clarify concepts and make the guide more accessible to new developers. The user added clarifications about message encoding, naming conventions, and the purpose of various system components. Furthermore, they introduced FAQs to the onboarding document.
paymentsethereumraidenblockchainweb3
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