Schema is Cedar's Super Power

In the ever-evolving field of authorization, balance is everything. You want expressiveness—but you need correctness and performance at scale.

Cedar’s designers rooted the language in a strong type and shape system—called schema. Every entity appears in Cedar policies only if it’s defined in advance, with named attributes and relationships. For policy writers, this delivers immediate clarity: variables like article.owner or device.region are grounded in concrete definitions, not ambiguous free-form values.

Patching the Gaps in OPA and OpenFGA

Rego policies operate over JSON data, and it's up to the OPA policy author to validate or assume the structure of that data. OpenFGA is intentionally minimal. It doesn’t define: (1) Common properties of objects (like “title”, “createdBy”, “tags”); (2) data types or schemas in the traditional sense (string, integer, etc.); (3) Object metadata or validation rules outside of relationships. OpenFGA’s scope is authorization relationships only. It’s deliberately decoupled from data schema.

Governance and Evolution: Schema as Policy Anchors

A provable linkage between schema and policy ensures that everyone—from developers to auditors—is working with the same shared model. It helps prevent drift during system upgrades, refactorings, or macro-level changes. When enterprise systems evolve, your schema evolves too—and policy validity is automatically rechecked against it. Schema helps enterprises scale governance and reduce risk.

Schema as the Foundation for Change Management

As your infrastructure adds new attributes, services, or relationships, using an authorization schema makes the process straightforward and repeatable. Rather than patching or bolting on authorization logic, schema-aligned Cedar policies evolve with your data model—in lockstep. It’s proactive policy evolution.

🚀 Looking Ahead: Cedar's Schema-Centric Future

Schema is not just a convenience—it’s the plumbing that makes Cedar provable, performant, and evolvable. Schema requirements empower:

1. Automated reasoning at scale, enabling universal assertions of safety.
2. Static validation, preventing common mistakes and drift.
3. Enforceable alignment with data models
4. Governance-ready policy evolution, without sacrificing confidence or clarity.

Schema makes Cedar far more than “another policy DSL.” It gives you a foundation for reasoned authorization, where policies are not guesswork or brittle rules—but mathematically grounded, human-readable, and tightly integrated with your systems, data and infrastructure.

Final Takeaway

Cedar builds its policies on a strong grammatical backbone—a schema. This isn’t by-product. It’s a Super Power--transforming authorization from tacit agreement into provable, scalable, and evolvable policy governance. If you’re building next-gen access control systems—especially data-centric ones—you’re wise to bet on schema-first authorization. Cedar is more then just a pretty policy syntax!

Want to try Cedar in your application? Check out the Cedarling!