Nicolas Grégoire (aka @Agarri_FR) has nearly 20 years of experience in penetration testing and auditing of networks and (mostly Web) applications. He is an official Burp Suite Pro trainer since 2015, and trained hundreds of people since then, either privately or during infosec events. Outside of that, he runs Agarri, an one-guy company where he finds security bugs for customers and for fun.
His public security research (that mostly deals with XML, XSLT and SSRF) was presented at numerous conferences around the world (HackInTheBox, ZeroNights, HackInParis, Nullcon, …).
He was also thanked by numerous vendors for responsibly disclosing vulnerabilities in their products and services, directly or through bug bounty programs.