- Handle Name
- kcz or Cookies or こおしいず 1
- PGP Fingerprint
598C8E59DE9C21FFEB434A3E 80B59E49 D6D9B0FD[Keybase]
- Graduated from Dept. of Information Science, School of Science, Univ. of Tokyo
- Niigata, Japan
- Class 1 Driver’s License in Japan
- KanKen Grade 3
- SuKen Pre-2nd Grade
- EIKEN 2nd Grade
- Applied Information Technology Engineer Examination
- FetchDecodeExecWrite (an ISUCON team)
- Theoretical Science Group (a club in the University of Tokyo + a CTF team)
- wasamusume (a CTF team)
Please visit links.
- ISUCON book review: reviewed a part of a Japanese book about web service performance tuning from ISUCON contest perspective. Title: 達人が教えるWebパフォーマンスチューニング 〜ISUCONから学ぶ高速化の実践, ISBN:
978-4-297-12846-3[技術評論社 (publisher)], [Amazon.co.jp]
- CTF book review: reviewed the Web genre part of a Japanese book about CTF. Title: 詳解セキュリティコンテスト CTFで学ぶ脆弱性攻略の技術, ISBN:
978-4-8399-7349-0[マイナビ出版 (publisher)], [Amazon.co.jp]
- TSG CTF 2021: hosted a 24hr CTF with TSG members. [ctftime]
- ISUCON11: participated in Quals and got 3rd in Final as a team “FetchDecodeExecWrite”.
- Google CTF 2020: 2nd in Finals after 18th in Quals as a team “I Use Bing” (a joint team made of several Korean and Japanese independent teams). [video]
- LINE CTF 2021: 7th as a team “TSG”.
- ISUCON10: participated in Quals and got 6th in Final as a team “FetchDecodeExecWrite”.
- TokyoWesterns CTF 6th 2020: 9th as a team “TSG”.
- TSG CTF 2020: hosted a 24hr CTF with TSG members. authored 1 challenge. [ctftime]
- CTFZone 2020: 7th in Finals after 10th in Quals as a team “TSG”.
- ISUCON9: participated in Quals and Final as a team “FetchDecodeExecWrite”.
- TSG CTF: hosted a 24hr CTF with TSG members. authored 3 challenges. [ctftime]
- ISUCON8: 2nd in Quals and participated in Final a team “FetchDecodeExecWrite”(moratorium, akouryy and me) [my blog]
- CODE BLUE CTF 2018 Quals: 4th as a team “TSG”(many)
- CODE FESTIVAL 2015: passed Qual A (122nd) and participated in onsite event CODE FESTIVAL 2015.
- ACM ICPC 2015 Domestic Quals: 12nd as a team “tekito”(satos, kivantium and me), but I did nothing but printing.
- Security Camp 2013 in Tokyo: tutor in Software Security class
- SECCON CTF 2012 Final: 2nd prize as a team “wasamusume”(mimura, carme, dec, atgw, ytn and me) [blog]
- SECCON CTF 2012 in Yokohama: 1st as a team “wasamusume”
- Security Camp 2012 in Tokyo: student of Software Security class (in CTF, won 1st prize as a team "|" (4 members including me) and MVP as an individual)
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call me like “koh-sheeze”. “cookies” / “k-c-z (kay-sea-zee)” are also acceptable. ↩