Kei Hayashi
プロダクトマネージャー at Repro Inc.
Chiyoda, Japan
Summary
👤
Senior🎓
Top SchoolKei Hayashi is a Tokyo-based software engineer and product manager at pixiv Inc, where he combines backend development with product leadership and ongoing OSS work. He steers scalable backend systems and contributes to open‑source tools, including Jipcode (Japan's postal code/address converter) and RTram (a static site generator). With 16 years of experience, he codes in Ruby, JavaScript/Node.js, and Python, and works with Rails and Django, leveraging GCP and AWS to ship reliable services. His GitHub profile reveals a strong Haskell focus as the author of Haskell Relational Record and a contributor to ghc-mod, underscoring a breadth of language fluency and tooling expertise. Prior to pixiv, he served as a Technical Solutions Consultant at Repro Inc and built a solid foundation in engineering and cross-functional collaboration. Based in Chiyoda, Tokyo, he thrives at the intersection of product strategy and hands-on engineering, turning complex requirements into practical, scalable solutions.
16 years of coding experience
5 years of employment as a software developer
Bachelor's degree, Department of Electronics and Information Engineering, Bachelor's degree, Department of Electronics and Information Engineering at Nara National College of Technology
Github Skills (10)
ghc10
commandline-interface10
command-line-interface10
haskell10
commandline10
command-line10
cli10
build-automation9
cabal8
elisp7
Programming languages (8)
Github contributions (5)
DanielG/ghc-mod
Oct 2011 - Jan 2015
Happy Haskell Hacking for editors. CI: https://gitlab.com/dxld/ghc-mod/pipelines
Role in this project:
Backend Developer
Backend DeveloperContributions:6 commits, 2 PRs, 1 comment in 3 years 3 months
Contributions summary:Kei focused on enhancing the `ghc-mod` tool's functionality, particularly regarding GHC options. They implemented features to pass GHC options directly to the check command and modified the build process to incorporate cabal-dev configuration files. Furthermore, the user updated the help message, and re-added a global option for expanding commands within the tool. These changes improve the tool's flexibility and usability for Haskell development.
ghcmodhaskellcabalgitlab
khibino/cpdt-japanese
Sep 2018 - Sep 2020
Certified Programming with Dependent Types (Japanese Translation)
Contributions:47 pushes, 4 branches in 2 years 1 month
dependent-typestuplegleamtranslationjapanese
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