Open Policy Agent

Open Policy Agent (OPA) is an open-source, general-purpose policy engine graduated under the Cloud Native Computing Foundation (CNCF) that unifies and standardizes policy enforcement across the modern cloud-native technology stack. OPA decouples operational policy decision-making from software service logic, providing organizations with a unified declarative policy language known as Rego to author, evaluate, and enforce fine-grained governance rules. Using OPA, engineering and security teams can express complex authorization and compliance rules as code across diverse architectural components, including Kubernetes admission control via Gatekeeper, API gateways, microservice service meshes, CI/CD deployment pipelines, and public cloud infrastructure managed by Terraform. When a software component evaluates an action, it queries OPA with structured JSON data representing the request; OPA executes the corresponding Rego policies against that context and returns an authoritative decision, such as allow or deny, along with detailed audit telemetry. OPA features integrated unit-testing frameworks, policy debugging tools, and distributed deployment models that run as local sidecars or daemon services, ensuring high-throughput, microsecond-latency policy evaluations without external network dependencies. OPA empowers modern cloud platform teams to implement scalable guardrails and continuous regulatory compliance.