Explore a presentation from NSDI '19 on Riverbed, a groundbreaking framework for creating privacy-conscious web services. Learn how users can define restrictions on sensitive data processing and storage using a simple policy language. Discover the role of the transparent Riverbed proxy in mediating between front-end clients and back-end servers, and understand the remote attestation process that ensures server code compliance with user policies. Delve into the concept of universes, which allow Riverbed to work seamlessly with legacy software without requiring developers to navigate complex security lattices or manually label code. Examine the framework's performance impact, with experimental results showing minimal slowdowns for real-world applications. Gain insights into user-defined policies, remote attestation, and the innovative approach to enforcing privacy constraints in distributed web services.