Leon's two decades of expertise were concentrated on architecting and operating complex, web-based systems to withstand crushing traffic (often unexpectedly). Over the years, he's had a somewhat unique opportunity to design and build systems that run some of the most visited websites in the world. While his core expertise is in application development, he works his way around the whole technology stack from system architecture to databases design and optimization to front/back-end programming. He's considered a professional naysayer by peers and has the opinion that nothing really works until it works for at least a million people.