In this deep dive session from AWS re:Invent 2023, Amazon S3 engineering leaders Amy Therrien and Seth Markle provide an insider's look at the architecture and design principles behind S3's industry-leading durability, availability, and performance. They explain S3's threat modeling process for anticipating and mitigating potential issues, and how features like multi-part uploads and multi-value DNS enable massive scale. The speakers also detail S3's approach to data redundancy across availability zones, proactive monitoring for drive failures, and guardrails to ensure correctness. This technical session offers valuable insights into how S3 achieves 11 nines of durability while serving over 100 million requests per second.