Global Fujitsu Distinguished Engineer

Motohiro Kosaki


I have been striving to change the world in the field of OSS.
I am thrilled at the recognition of the role of these activities in boosting Fujitsu's presence.


  • Developed the Linux memory management reclaim system as a core developer.
  • Developed Ruby core as the Ruby core team and the security team.
  • A councilor of Ruby Association.
  • Member of Ruby Biz Grand Prix Committee.


    Japan OSS Contributor Award
  • Northeast Asia OSS Contributor Award

Value Creation

As a Linux hacker, he standardized high-end enterprise requirements (hot-plugging, tracing, containers) into the Linux kernel. And then moved to Red Hat as a partner engineer, where he successfully developed the RHEL kernel. After that, he wrote new Ruby GIL (Global Interpreter Lock) from scratch, standardized arm64 AI stack for Fugaku into oneDNN, et al. He has been increasing his presence in the OSS world.