Product Releases
May 25, 2023
3 min read

New Horizons with Kong Gateway 3.3 for Open Source

Tom Brightbill
Group Product Manager

As API usage and dependence continue to grow, the need for a reliable, performant, and secure API gateway has become even more essential. Kong Gateway Open Source continues to be the world’s most adopted API gateway, setting the benchmark for performance, reliability, and observability.

Today, we’re excited to unveil Kong Gateway 3.3 for Open Source, a release that once again elevates the API gateway experience to new heights.

OpenAPI Spec for Kong OSS

Kong is thrilled to announce an OpenAPI Spec (OAS) for the Kong admin API. OAS specs are critical for organizations as they navigate and consume APIs. They provide a single source of truth as to the shape of a given API that is referenceable by all who consume the API.

By providing a machine-readable, easily shareable specification, we encourage third-party developers and partners to leverage our APIs creatively. Moreover, embracing an OpenAPI spec reinforces our commitment to transparency and open standards.

View all of Kong's published specs at

Configurable queuing behavior

A key feature in this release is the introduction of configurable queuing behavior for key tracing, metrics, and logging plugins, including HTTP Log, StatsD, OpenTelemetry, and Datadog. These plugins now expose configurations to govern their queuing behavior, enabling operators to limit the size of queues and prevent the gateway from over-consuming memory when queues can't be processed. This ability to fine-tune the gateway ensures that performance doesn't suffer at the expense of maintaining observability metrics dogmatically.

By allowing operators to limit queue size, Kong ensures that the gateway doesn't overconsume memory, particularly during periods when an upstream logging endpoint isn’t available. If the queue reaches a user-defined limit, it can then be configured to flush, thereby optimizing memory use while awaiting the upstream to come back online.

Furthermore, version 3.3 enables the configuration of the maximum duration for retries when queueing is used, replacing the previous method of specifying the number of retries. This enhancement, in conjunction with the underlying exponential backoff algorithm, improves the predictability of Kong Gateway’s behavior. Below is a screenshot of the new queue configuration experience.

You can read more about how to configure the new queueing logic here. Additionally, we'll be following up with a technical blog post on this topic.

High-scale reliability with readiness probes

Ensuring precision in the configuration of an API gateway is paramount. The introduction of a readiness probe status endpoint is particularly useful for customers using the Kong Ingress Controller or Kong with Kubernetes. This functionality allows Kubernetes users to set a readiness probe on the pods running Kong to ensure they don't receive any traffic until they've received a valid configuration, thereby preserving the integrity and security of incoming traffic.

OpenTelemetry plugin improvements

OpenTelemetry (also referred to as OTel) is a powerful open-source observability framework. Our new release includes significant usability improvements to this plugin. This enables deep visibility into every API call, helping users understand where calls are spending time within each stage of the Gateway as well as the upstream application.

The specific experience improvements of our OpenTelemetry plugins are as follows:

  • Ensuring that the span hierarchy for intra-Kong calls is accurate. Any span that includes calls to multiple Kong services is appropriately aggregated and displayed.
  • Easily identify spans. Kong-specific spans are now named and grouped in an intuitive way that describes the types of spans (e.g., ‘kong.router', ‘kong.dns').
  • Improved propagation support to associate Kong requests to external (incoming) requests. Kong now has robust support for associating Kong spans to external services, giving users an end-to-end view that includes Kong Gateway.
  • Additional improvements to the timing exposed in Kong-specific spans to ensure the accuracy of latency/timing data.
  • The ability to set a tracing header from Kong when Kong is the first request in a series of spans including your upstream services

These enhanced features of the OpenTelemetry plugin clearly demonstrate Kong’s ongoing commitment to user-focused improvements for API Gateway observability.

Kong Gateway Open Source 3.3 is a testament to our unending dedication to our community, delivering top-tier features and performance. Stay tuned for a technical deep dive into the new features of this release in an upcoming blog post. Embrace the future of API gateways with Kong!

Download Kong Gateway 3.3 for OpenSource. Or sign up for Kong Konnect for free. It's the fastest way to experience Kong Gateway 3.3.