OpenFeature, an open-source specification that provides a community-based and vendor-agnostic application programming interface for feature flagging in software development, has been accepted as the latest incubating project by the Cloud Native Computing Foundation.

Today’s announcement is a key milestone for the OpenFeature project, which is helping accelerate the adoption of feature flags in application development. Feature flags are essentially a kind of switch that integrates with applications, enabling developers to switch on or off specific features within an app at runtime, without deploying any new code.

They’re becoming popular because of the pressing need for organizations to release new software at high velocity in order to stay competitive and remain at the forefront of innovation. However, new software updates cannot sacrifice on quality. So agile companies that have adopted continuous software strategies use feature flagging to safely release code faster.

With feature flags, developers can decouple new feature releases from deployments. This allows them to test unreleased features in a safe environment with specific groups of users, without putting anyone else at risk.

Many companies today use their own, homegrown feature flagging tools, but these generally require lots of maintenance, putting a big burden on operations teams. As an alternative, companies can also use a number of commercial feature flagging tools, but though these provide updates and support, they often present interoperability challenges that complicate future software deployments.

OpenFeature is an open-source API that allows teams to get started using feature flags quickly and confidently. It can work with almost any kind of commercial or homegrown feature flagging tool, enabling teams to choose the method that fits their current requirements while being able to switch to a different method if requirements change.

The project pools the expertise of the feature flagging community to provide open solutions to the interoperability challenges it faces, for instance by providing an integration with OpenTelemetry. By standardizing feature flag tools, OpenFeature unifies the community behind a common interface, together with a framework for building extensions and integrations that any feature flag tool can easily adopt.

The OpenFeature project was first announced as a sandbox project by the CNCF in June 2022, and has won the backing of a number of commercial feature flag companies, including LaunchDarkly, Split Software Inc., CloudBees Inc. and Flagsmith. It has also seen significant adoption, with some of its biggest users including Google LLC, SAP SE and Spotify Inc.

The CNCF’s continued backing of the project is a strong validation of its usefulness, and should help to accelerate its momentum. The CNCF is a Linux Foundation affiliate that manages dozens of open-source projects, including foundational technologies such as Kubernetes and the Prometheus observability platform. Projects housed under its umbrella benefit greatly from increased exposure to the open-source development community, which helps to grow their adoption among enterprises.

Having graduated from a sandbox to incubating project, OpenFeature’s community is now focused on driving further standardization around feature flags. It intends to build on its existing definition for a flag evaluation software development kit and create additional standards, including a wire protocol for remote flag evaluation and a standard flag definition format.

Lukas Reining, a member of the technical committee that steers the development of OpenFeature, said the tighter integration within the CNCF’s ecosystem will help to operationalize the concept of cloud-native feature flagging. “I am really looking forward to continuing the evolution of OpenFeature,” he said. “[Ensuring] feature flagging helps projects and organizations get the most value out of feature flagging with a great experience.”

Image: OpenFeature