The eighteen-service gRPC mesh now carries an authentication framework where each service declares its own authentication policy independently. Enforcement is optional per service — the same runtime supports services that are fully open (internal, behind a network boundary), services that require mTLS-only, services that require JWT plus mTLS, and services that route to a custom authenticator for bespoke policies.
- Per-service policy declaration. Each service's deployment descriptor declares the authentication mechanism it requires. The mesh refuses to call a service without honouring its declared policy ; cross-service calls that lack credentials fail at the interceptor, not deep inside the service logic.
- Staged rollout. Compliance audits often demand "this specific service must require authentication by date X, the rest can follow." The framework supports staged enforcement so the audit-critical service locks down without forcing the rest of the mesh to migrate in lock-step.
- Mixed-mode deployments. Federated architectures with one tenant's services in a high-security zone and another tenant's in a development zone run on the same runtime ; policy is data, not code.
- Pluggable authenticators. Customer-specific authenticators (token introspection against a corporate IdP, hardware-token validation, certificate-pinning) plug into the framework without forking the platform.