How do you stop a half billion dollars in cryptocurrency from being stolen? You perform software testing and responsibly disclose it first, of course.

Yannis Smaragdakis, a researcher with Dedaub, found a major vulnerability in Ethereum smart contracts, arguably within the billion-dollar range, that would have made it one of the largest hacks ever—given that it was a theoretically unbounded threat -- had it not been mostly mitigated by the time it went public.  In this episode he steps us though how he discovered the Phantom Function and other vulnerabilities within Ethereum.