I've extracted a summary of the text in one paragraph. Here's an overview of Authzed's SpiceDB authorization tooling: SpiceDB is a relationship-based system for implementing fine-grained permissions, inspired by internal systems at Google and Facebook. To address ABAC (Attribute-Based Access Control) limitations, Authzed introduced "caveats," which are functions defined using Google's CEL expression language, allowing for dynamic policies like "during these hours" or "with an IP addresses in this subnet." Caveats leverage SpiceDB's distributed caching layer, enabling instant evaluation of caveat expressions and meeting properties of scale and latency. This innovative approach aims to provide a scalable solution for secure, expressive permission systems that can handle complex use cases.