GrowthBook

New edition of The Experimentation Edge: Chess.com runs 400 experiments a year for a user base that spans people who don't know how pieces move and FIDE-rated competitors. Here's what that skill gap forces them to get right. Nafis Shaikh (Director of PM at Chess.com) breaks down the four-metric framework his team uses to prioritize experiments, why the gameplay team is explicitly not allowed to optimize for revenue, and the Game Review test that lifted subscription conversions by leading with wins instead of losses. Worth reading if you're designing tests for a user base that doesn't behave like a single cohort.