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 product manager and backend engineer with 17 years of experience building e-commerce platforms and developer tools. Currently at pixiv Inc., he combines product ownership with hands-on backend work (Ruby, Node, Python) and cloud operations on GCP/AWS, drawing on prior engineering and technical consulting roles. He maintains several OSS projects—such as a Japanese postal-code/address converter and a static site generator—and has contributed Haskell-focused tooling like enhancements to ghc-mod. Comfortable spanning Rails and Django stacks, Kei also brings an uncommon mix of Haskell library experience and practical product delivery, making him fluent in both developer ergonomics and production reliability.
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 (8)
command-line10
command-line-interface10
haskell10
cli10
ghc10
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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