Best Open-source Feature Flags tools

Split

Rack‑based A/B testing framework for Rails, Sinatra, and more

GrowthBook

Open Source Feature Flagging and A/B Testing Platform

Flipt

Git-native feature management platform for modern development teams

Flagr

Deliver targeted experiences with feature flags and A/B testing

FeatureHub

Cloud Native feature flags, A/B testing, and remote configuration platform

GO Feature Flag

Lightweight, multi-language feature flag service with relay proxy

Featurevisor

Git-based feature flags and experimentation for developers

Flagsmith

Open-Source Feature Flagging and Remote Config Platform

Bucketeer

Feature flag management and A/B testing platform

FeatBit

Self-hosted feature flag platform for safe deployments

Unleash

Feature flag platform enabling safe, incremental releases

Flagger

Progressive delivery automation for Kubernetes with canary deployments

Flipper

Beautiful, performant feature flags for Ruby and Rails

Togglz

Dynamic runtime feature toggles for Java applications

Rollout

Redis-backed feature flags for Ruby with granular rollout control

FeatureProbe

Open source feature management for confident, low-risk deployments