How do you keep millions of people safe on 40 different dating sites while simultaneously figuring out what drives them to buy memberships? Sean Corfield joins Adam and Ben to discuss the surprisingly complex engineering and business challenges of observing user behavior at massive scale.

Sean runs us through fraud detection and prevention (including devastating "pig butchering" romance scams), database architecture at enormous scale (700GB databases with 250M+ row tables), custom domain-specific languages for writing business rules without touching SQL, real-time scoring systems with hundreds of rules, zero-downtime deployments and schema migrations, and the constant cat-and-mouse game between scammers and detection systems.

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With audio editing and engineering by ZCross Media.

Full show notes and transcript here.