OPAL
Policy and data administration, distribution, and real-time updates
...The project aggregates policy and data from external sources, watches for changes, and distributes updates to connected policy agents. It is built for cloud-native and microservice environments where authorization rules change frequently and need to propagate quickly. OPAL separates policy decision-making from policy distribution, which helps teams build more maintainable and consistent permission systems. It is especially useful for engineering teams implementing fine-grained authorization, relationship-based access control, feature access rules, and multi-service policy governance.