Joshua Hill (aka [@p0sixninja](https://twitter.com/p0sixninja)), has been an inspirational (yet sometimes controversial) figure in the iOS Jailbreaking scene for many years. He was the chief architect and developer for the software used in the GreenPois0n and Absinthe jailbreaks, and also performed research to help find and exploit many of the vulnerabilities used. He currently works as the CRO of Sudo Security Group, the company creating Guardian Mobile Firewall; the first and only smart firewall for iOS.