Netflix Builds GenPage: A Generative AI Model for Personalized Homepages

Netflix's GenPage is a generative AI system that directly generates personalized homepages for users, replacing the traditional multi-stage pipeline. By using a prompt-response paradigm, it unifies item selection, row construction, and layout generation into one model. Post-training reinforcement learning (RL) optimizes the entire page, considering cross-row and item-level interactions. A/B tests show statistically significant improvements in user engagement and a 20% reduction in end-to-end service latency. Notably, enriching prompts yielded greater performance gains (6.9% WBC loss reduction) than scaling model parameters from 120M to 900M (1.3% reduction), though prompt benefits plateau as context saturates. GenPage also offers greater flexibility for different content types and easier expansion for new product experiences.