GO Feature Flag

GO Feature Flag provides a self‑hosted, cloud‑native implementation of feature flags that can be used from any language through the OpenFeature standard. It stores flag definitions in a simple file format and can retrieve that file from sources such as the file system, S3, Google Cloud Storage, GitHub or Kubernetes ConfigMaps. The server evaluates flags against an evaluation context, supporting targeting of users, segments, environments, complex rollout strategies and percentage rollouts.

Developers can integrate the solution with client SDKs for Go, Java, Kotlin, .NET, Python, JavaScript/TypeScript, React, Angular, Swift, Node.js, PHP, Ruby and more, allowing feature toggles to be controlled without code changes. The platform also offers notifiers and exporters to send change events to Slack, webhooks or data stores, and it can collect usage metrics for analysis.

The project is released under the MIT license, is fully open source, and requires no subscription or external service. It is positioned as a lightweight alternative to commercial flag services, emphasizing easy setup, vendor neutrality and compatibility with the broader OpenFeature ecosystem.