Custom Resource Definitions (CRDs) were introduced into upstream Kubernetes by Red Hat engineers in version 1.7. From the beginning, they were designed as a future-proof implementation of what was previously prototyped as ThirdPartyResources. The road of CRDs has focused on the original goal of making custom resources production ready, bringing it to be a generally available feature in Kubernetes, highlighted with the promotion of the API to v1 in 1.16.

CRDs have become a cornerstone of API extensions in the Kubernetes ecosystem, and is the basis of innovation and a core building block of OpenShift 4. Red Hat has continued pushing CRDs forward ever since, as one of the main drivers in the community behind the features and stability improvements, which finally lead to the v1 API. This progress made OpenShift 4 possible.

Let’s take a deeper look at what will change in the v1 API of Custom Resource Definitions (in the apiextensions.k8s.io/v1 API group). The main theme is around consistency of data stored in CustomResources:

We’re pleased to announce the delivery of Kubernetes 1.16, our third release of 2019! Kubernetes 1.16 consists of 31 enhancements: 8 enhancements moving to stable, 8 enhancements in beta, and 15 enhancements in alpha.

Kubernetes 1.16 is expected to arrive this week, and with it comes a host of new changes that help ease management for users of this container orchestration platform. For users of Kubernetes, and of Red Hat OpenShift, this release signals the arrival of the general availability for Custom Resource Definitions (CRDs).

When building open source software, duties and tasks must be distributed among large numbers of contributors, some of whom may even be in direct competition with one another. While this may sound like a risky, Machiavellian scenario, in practice, there’s far less rivalry. Instead, the whole project becomes a collaborative board game with individual high scores.

Those high scores ebb and flow as teams take charge of features, lead them to completion and exchange leadership roles over the course of the development of the project. We say all that to say this: Kubernetes 1.16 saw a great deal of work and guidance across the ecosystem, as well as from Red Hat and Google (top upstream corporate contributors). All vendors and the community at large can benefit from the updates made in this release, especially with the prime time for CRDs, which are a main extension point for building cloud native applications on Kubernetes.