Yoshinori Takesako is the executive committee chairperson, organizer, and challenge creator of the SECCON CTF contests that are held several times a year throughout Japan including large international online and in-person contests. He is also on the OWASP Japan advisory board, the review board for the CODE BLUE conference, a Microsoft MVP of Developer Security, the leader of the Shibuya Perl Mongers group, and has been designated an expert in ISO/IEC JTC 1/SC 22 programming languages such as C# and other scripting languages. He has also presented at information security conferences such as HITCON in 2011 "Disassembling Flash Lite 3.0 SWF Files", and OWASP AppSec APAC 2014 "Secure escaping method for the age of HTML5", and has published some books and papers:"Reading ECMA-262 Edition 5.1" and "How to Execute Arbitrary Code on x86 JIT Compliers" etc.