In simple English
This tool lets you hide new features from most people while you test them. You control who sees what through a web dashboard. If something breaks, you turn the feature off instantly without pushing new code. You can run it on your own server for free, or pay for their cloud version. It is best for teams that want safe releases and gradual rollouts.
What it is
Unleash is a feature flag system with an admin server and software development kits for many languages. It helps you toggle features on and off for specific users or environments.
What it is good for
Solo builders who want to test new features with a small group of users before releasing them to everyone.
- Runs locally with Docker so you can try it immediately.
- Supports many programming languages with official client libraries.
- Lets you turn off broken features instantly without a new release.
- Uses AGPL-3.0 licence which requires sharing modifications if you host it as a service.
- Requires a running PostgreSQL database and Docker to self-host.
- Advanced security features like single sign-on require paid enterprise plans.
Hardcoded configuration files or environment variables for turning features on and off.
Docker and PostgreSQL for running the server.
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git clone git@github.com:Unleash/unleash.git cd unleash docker compose up -d