Kai Ohlhus
Senior Data Engineer At Rakuten Group, Inc.
Tokyo, Japan
Summary
🤩
Rockstar🎓
Top SchoolKai Ohlhus is a Senior Data Engineer at Rakuten Group with 12 years of experience building cloud-native infrastructure for large-scale machine learning, specializing in Kubernetes-based distributed training and model deployment. With a doctoral background in mathematics and computer science, he bridges rigorous research—verified numerical computations and reproducible HPC workflows—with production engineering to turn ML experiments into market-ready systems. He is fluent in C/C++, Python and Java, leverages container technologies end-to-end, and has hands-on experience operating NVIDIA GPU clusters. An active contributor to scientific packaging via Spack, he ensures optimized builds of numerical libraries (OpenBLAS, SuiteSparse, Octave) for high-performance workloads. Based in Tokyo, he combines academic depth with practical tooling and automation skills that reduce friction between experimentation and production.
12 years of coding experience
8 years of employment as a software developer
Doctor's Degree, Mathematics and Computer Science, Doctor's Degree, Mathematics and Computer Science at Hamburg University of Technology
German, English, Japanese
Stackoverflow
71reputation
3kreached
1answer
0questions
Github Skills (12)
package-manager10
spack10
package-management10
scientific-computing10
suitesparse9
octave9
build-tools9
openblas9
hpc8
automations8
automation8
python7
Programming languages (13)
Github contributions (5)
spack/spack
Jan 2020 - Oct 2022
A flexible package manager that supports multiple versions, configurations, platforms, and compilers.
Role in this project:
Automation Engineer / Build & Release Engineer
Automation Engineer / Build & Release EngineerContributions:8 reviews, 26 commits, 28 PRs in 2 years 9 months
Contributions summary:Kai primarily contributes to the Spack package manager by adding and updating package definitions. They add new versions of scientific software packages like Octave, SuiteSparse, and OpenBLAS, ensuring they are available for users. Furthermore, they add specific configurations and options for these packages, including enabling ILP64 support and adding new OpenBLAS versions. These changes are crucial for providing up-to-date and optimized scientific computing software within the Spack ecosystem.
compilerspythonradiussplatformslinux
gnu-octave/octave-publish
May 2016 - Aug 2016
Contributions:2 releases, 51 commits, 35 pushes in 3 months
Find and Hire Top DevelopersWe’ve analyzed the programming source code of over 60 million software developers on GitHub and scored them by 50,000 skills. Sign-up on Prog,AI to search for software developers.