Security, observability, and state modules are now standard in Varnish Enterprise Announcement

Published September 21, 2026.

With the release of Varnish Enterprise 6.0.18r5, vmod-ratelimit, vmod-cwt, varnish-otel, vmod-kv, and vmod-nodes are promoted to General Availability (GA) and included as standard Varnish Enterprise features. These modules previously required a separate Licensed Add-on license; they are now available in every Varnish Enterprise deployment without an add-on license or configuration change.

What’s included

Security and access control

  • vmod-ratelimit: cluster-wide rate limiting coordinated via an external NATS message broker, for PoP-level or global abuse mitigation. This is distinct from vmod-vsthrottle, which handles single-node rate limiting.
  • vmod-cwt: CBOR Web Token (CWT) validation at the edge, for Common Access Token (CAT) workflows, IoT, and binary-token authentication.

Edge compute, routing, and state

  • vmod-kv: state management operating locally or via a distributed backend such as Valkey or Redis, for cluster-wide session state, dynamic A/B allocation, and edge compute logic in VCL.
  • vmod-nodes: backend definitions driven by configuration files, with dynamic updates so routing topologies can change without a VCL reload.

Observability

  • varnish-otel: OpenTelemetry export of logs, metrics, and traces to backends such as Grafana, Datadog, and Honeycomb.

Performance

This release also ships an enhanced, experimental payload data allocator purpose-built for Massive Storage Engine (MSE4), improving memory density and reclaim speed for large allocations. It is disabled by default; set the yalloc_enable parameter to enable it.

Upgrade notes

Customers already licensed for these add-ons see no operational change; existing configuration continues to work as before.

References


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