growthbook

GrowthBook is an open-source platform for feature flagging, A/B experimentation, and product analytics, designed for engineering and product teams who want to control feature rollouts and measure their impact without vendor lock-in. It allows users to run experiments directly from their codebase, analyze results with built-in statistical engines, and manage flags through a self-hosted or cloud interface. Its appeal lies in combining these capabilities in a transparent, customizable tool that avoids the high costs and data privacy concerns of proprietary alternatives.