Profile / プロフィール
- Takashi Yoneuchi is Executive Vice President and Co-CTO at GMO Flatt Security Inc. He joined the company in 2019 and became CTO in June 2021. He leads research and development of Takumi byGMO, a security platform addressing two challenges in modern software: vulnerabilities and malicious code. Its capabilities include AI-powered security assessment and remediation, Takumi Guard for blocking malicious packages, and Takumi Runner for protecting CI/CD environments. He previously led development of Shisho Cloud and KENRO. He serves on the CODE BLUE review board and was Head Captain of Team Asia at the International Cybersecurity Challenge 2023. His work also includes a quantum-classical programming language project supported by the IPA MITOU Target Program and security education through Security Camp. He is the author of 『Webブラウザセキュリティ』 and a co-author of 『詳解セキュリティコンテスト』.
- 米内貴志。GMO Flatt Security株式会社 取締役副社長 Co-CTO。2019年に入社し、2021年6月にCTOに就任。現代ソフトウェアの「脆弱性」と「悪性」という2つの問題に向き合う『Takumi byGMO』の研究開発を牽引する。AIによる脆弱性の診断・修正に加え、悪性パッケージをブロックする『Takumi Guard』や、CI/CD環境を保護する『Takumi Runner』などを通じて、開発組織のセキュリティを支える。これまでに『Shisho Cloud』『KENRO』の開発・プロダクトマネジメント・事業開発に従事。CODE BLUEレビューボード、International Cybersecurity Challenge 2023 アジア代表チーム Head Captain 等を歴任。IPAの未踏ターゲット事業に採択された古典・量子ハイブリッドプログラミング言語の開発や、セキュリティ・キャンプでの教育活動にも携わる。著書に『Webブラウザセキュリティ』（2021年、ラムダノート）、共著に『詳解セキュリティコンテスト』（2021年、マイナビ出版）等。
Work Experience
- Currently Executive Vice President and Co-CTO. I joined Flatt Security in May 2019, became CTO in June 2021, and joined the board in June 2022. The company joined GMO Internet Group in February 2024 and changed its name to GMO Flatt Security in January 2025.
- Developing Takumi byGMO to address vulnerabilities and malicious code in modern software. I lead research and development of a security platform that helps engineering teams tackle both unintended security flaws and deliberately malicious software. Alongside AI-powered vulnerability assessment and remediation, Takumi includes Guard to block malicious packages and Runner to protect CI/CD environments.
- Led development of Shisho Cloud. My responsibilities spanned product management, business development, and product engineering, including customer interviews, product strategy, and building the engineering team. The product evolved from Policy as Code and cloud security management toward automated security assessment.
- Led development of KENRO byGMO, a secure coding training platform. I designed and developed much of the initial codebase, including the sandbox and automated evaluation of learners' code fixes, and supervised training content. The evaluation system is covered by Japanese Patent No. 7463021. I also worked on business development and sales during the launch phase.
- Worked on DNS security and co-invented a method for detecting homograph attacks.
- Did vulnerability testing of Web applications.
Education & Certifications
- Received B.Sc. in Information Science, as a student of Hagiya Laboratory.
- The reference GPA is about 3.82/4.0; the value is based on Japan-U.S. Educational Commission since the University of Tokyo does not provide the official GPA.
- 93 credits in Senior Division (Department of Information Science): 42 A+ (優上; 100-90), 30 A (優; 89-80), 7 B (良; 79-65), 8 C (可; 64-50), 6 Pass (for pass-or-fail basis credits)
- 69 credits in Junior Division (College of Arts and Sciences): 37 A+ (優上; 100-90), 23 A (優; 89-80), 3 B (良; 79-65), 0 C (可; 64-50), 6 Pass (for pass-or-fail basis credits)
- Score: 91/120 (Reading: 27/30, Listening: 23/30, Speaking: 17/30, Writing: 24/30)
- I've experienced 1-2 years of working with English-speaking colleagues after this test ― I believe my English skills have improved since then :-)
Publications
- ISBN: 978-4-8144-0010-2
- Author: Gerard Gallant
- Translator: 北原 憲, 洲崎 俊, 西谷 完太, 磯野 亘平,
米内 貴志 (me)
- See this page for further information of this book.
- ISBN: 978-4-839973-49-0
- Author: 梅内 翼, 清水 祐太郎, 藤原 裕大, 前田 優人, 米内 貴志 (me), 渡部 裕
- See this page for further information of this book.
- ISBN: 978-4-908686-10-8
- Author: 米内 貴志 (me)
- See this page for further information of this book.
- Here is an abstract of the paper.
- Please email me to get the full version.
- Inventor: Takashi Yoneuchi (me)
- Patent ID: JP7463021B2
- Invented with my colleagues at Flatt Security.
- Inventor: Takashi Yoneuchi (me), Yuji Watanabe, Fumiko Akiyama
- Patent ID: US20200134102A1
- Invented with my colleagues at IBM Research - Tokyo.
R&D Projects
- Developed Qitten, a next-gen quantum-classical programming language.
- This project was supported by MITOU Target Program, a research grant for quantum projects.
- Reference: a project summary page
- Reference: slides
- Developed puppy, a tiny Web browser written in Rust for educational purposes.
- It's about 4k lines of code including tests.
- it can parse HTML/CSS, render it in your terminal, and even execute JavaScript with the v8 engine!
- Reference: the GitHub repository for this project.
Volunteer Experience
- Review talk submissions for the international cybersecurity conference CODE BLUE.
- Led the Asian representative team at the International Cybersecurity Challenge 2023.
- Provided some training courses on Web/product security.
- Supported trainers technically and mentally.
- Organized CTFs and trainings for beginners.
- Finding vulnerabilities of widely-used applications to make the world more secure!
- See this page to check a full list of CVEs.
