Keigo Oka
About Me
Software engineer living in Tokyo. I love solving and finding interesting problems, whether in the real world or in abstract mathematical settings.
Professional Experience
Senior Software Engineer, Google2014 – present
Public work includes:
- Files app for ChromeOS
- ChromeOS Virtual Keyboard
- Tast: Integration Testing Framework
- ChromiumIDE
Hobby Projects
- Creating Shogi (Japanese chess) problems, mainly helpmates
- Solving mathematical problems, sometimes via computer
- Writing a paper when I get a good result
Publications
- Keigo Oka. Turing Completeness of GNU find: From mkdir-assisted Loops to Standalone Computation. FUN 2026. arXiv slides blog
- Keigo Oka, Naoki Inaba, Akira Iino. Covering a Polyomino-Shaped Stain with Non-Overlapping Identical Stickers. FUN 2026. arXiv slides
- Ryosuke Nishi, Taro Takaguchi, Keigo Oka, Takanori Maehara, Masashi Toyoda, Ken-ichi Kawarabayashi, Naoki Masuda. Reply trees in Twitter: data analysis and branching process models. Social Network Analysis and Mining, 2016. paper
- Yoichi Iwata, Keigo Oka, Yuichi Yoshida. Linear-Time FPT Algorithms via Network Flow. SODA 2014. arXiv
- Yoichi Iwata, Keigo Oka. Fast Dynamic Graph Algorithms for Parameterized Problems. SWAT 2014. arXiv
Programming Contests
- TopCoder — peak rating 2766 (Red, as of 2011)
- Codeforces — peak rating 2302 (as of 2012)
- AtCoder — peak rating 2544 (as of 2017)
- ICFP Programming Contest — 5th place (2023), 6th place (2024, 2025), as part of a team
Education
- M.S. in Information Science and Technology, The University of Tokyo2014
- B.S. in Information Science, The University of Tokyo2012