Unleash is a powerful open-source solution for feature management. It streamlines your development workflow, accelerates software delivery, and empowers teams to control how and when they roll out new features to end users. With Unleash, you can deploy code to production in smaller, more manageable releases at your own pace.
Feature flags in Unleash let you test your code with real production data, reducing the risk of negatively impacting your users' experience. It also enables your team to work on multiple features simultaneously without the need for separate feature branches.
Unleash is the most popular open-source solution for feature flagging on GitHub. It supports 15 official client and server SDKs and over 15 community SDKs. You can even create your own SDK if you wish. Unleash is compatible with any language and framework.
To get started with Unleash, you can either explore [Unleash Enterprise](#unleash-enterprise) with a free trial or [get started locally](#unleash-open-source) with our open-source solution.
To start with Unleash Enterprise, [request a free trial](https://www.getunleash.io/plans/enterprise-payg?utm_source=oss&utm_medium=readme&utm_content=unleash-enterprise-start). This gives you access to a hosted instance with unlimited projects and environments and features such as [role-based access control](https://docs.getunleash.io/reference/rbac), [change requests](https://docs.getunleash.io/reference/change-requests), [single sign-on](https://docs.getunleash.io/reference/sso), and [SCIM](https://docs.getunleash.io/reference/scim) for automatic user provisioning.
#### Unleash Open Source
To set up Unleash locally, you'll need [`git`](https://git-scm.com/) and [`docker`](https://www.docker.com/) installed on your machine.
If you'd rather run the source code in this repo directly via Node.js, see the [step-by-step instructions to get up and running in the contributing guide](./CONTRIBUTING.md#how-to-run-the-project).
Checking the state of a feature flag in your code is easy! The syntax will vary depending on your language, but all you need is a simple function call to check whether a flag is available. Here's how it might look in Java:
If you don't want to run Unleash locally, we also provide easy deployment setups for Heroku and Digital Ocean:
[](https://www.heroku.com/deploy/?template=https://github.com/Unleash/unleash) [](https://cloud.digitalocean.com/apps/new?repo=https://github.com/Unleash/unleash/tree/main&refcode=0e1d75187044)
The above sections show you how to get up and running quickly and easily. When you're ready to start configuring and customizing Unleash for your own environment, check out the documentation for [getting started with self-managed deployments](https://docs.getunleash.io/reference/deploy/getting-started), [Unleash configuration options](https://docs.getunleash.io/reference/deploy/configuring-unleash), or [running Unleash locally via docker](https://docs.getunleash.io/tutorials/quickstart).
We know that learning a new tool can be hard and time-consuming. We have a growing community that loves to help out. Please don't hesitate to reach out for help.
[](https://slack.unleash.run)
💬 [Join Unleash on Slack](https://slack.unleash.run) if you want ask open questions about Unleash, feature toggling or discuss these topics in general.
📖 Learn more about the principles of building and scaling [feature flag](https://docs.getunleash.io/topics/feature-flags/feature-flag-best-practices) solutions.
Unleash is the largest [open-source feature flag solution](https://www.getunleash.io/) on GitHub. Building Unleash is a collaborative effort, and we owe a lot of gratitude to many smart and talented individuals. Building it together with the community ensures that we build a product that solves real problems for real people. We'd love to have your help too: Please feel free to open issues or provide pull requests.
Check out [the CONTRIBUTING.md file](./CONTRIBUTING.md) for contribution guidelines and the [Unleash developer guide](./website/docs/contributing/developer-guide.md) for tips on environment setup, running the tests, and running Unleash from source.
- Get an overview of all feature flags across all your environments, applications and services
- Targeted releases using [activation strategies](https://docs.getunleash.io/reference/activation-strategies) to enable and disable features for certain users or segments without having to redeploy your application.
- Out-of-the-box integrations with popular tools ([Slack](https://docs.getunleash.io/addons/slack), [Microsoft Teams](https://docs.getunleash.io/addons/teams), [Datadog](https://docs.getunleash.io/addons/datadog)) + integrate with anything with [webhooks](https://docs.getunleash.io/addons/webhook)
- [Insights for managing technical debt](https://docs.getunleash.io/reference/technical-debt) and [stale flags](https://docs.getunleash.io/reference/technical-debt#stale-and-potentially-stale-flags)
- [12 official client SDKs](https://docs.getunleash.io/reference/sdks#official-sdks), and 10 [community-contributed client SDKs](https://docs.getunleash.io/reference/sdks#community-sdks)
- Scale with [Unleash Edge](https://docs.getunleash.io/reference/unleash-edge) independently of the Unleash server to support any number of front-end clients without overloading your Unleash instance
Read more in the [_system overview_ section of the Unleash documentation](https://docs.getunleash.io/understanding-unleash/unleash-overview#system-overview).
If none of the official SDKs fit your need, there's also a number of [community-developed SDKs](https://docs.getunleash.io/reference/sdks#community-sdks) where you might find an implementation for your preferred language (such as [Elixir](https://gitlab.com/afontaine/unleash_ex), [Dart](https://pub.dev/packages/unleash), [Clojure](https://github.com/AppsFlyer/unleash-client-clojure), and more).
Unleash has evolved significantly over the past few years, and we know how hard it can be to keep software up to date. If you're using the current major version, upgrading shouldn't be an issue. If you're on a previous major version, check out the [Unleash migration guide](https://docs.getunleash.io/deploy/migration_guide)!
- [_Feature toggles — Why and how to add to your software_ — freeCodeCamp (YouTube)](https://www.youtube.com/watch?v=-yHZ9uLVSp4&t=0s)
- [_Feature flags with Unleash_ — The Code Kitchen (podcast)](https://share.fireside.fm/episode/zD-4e4KI+Pr379KBv)
- [_Feature Flags og Unleash med Fredrik Oseberg_ — Utviklerpodden (podcast; Norwegian)](https://pod.space/utviklerpodden/feature-flags-og-unleash-med-fredrik-oseberg)
- [_Designing the Rust Unleash API client_ — Medium](https://medium.com/cognite/designing-the-rust-unleash-api-client-6809c95aa568)
- [_FeatureToggle_ by Martin Fowler](http://martinfowler.com/bliki/FeatureToggle.html)
- [_Feature toggling transient errors in load tests_ — nrkbeta](https://nrkbeta.no/2021/08/23/feature-toggling-transient-errors-in-load-tests/)
- [_An Interview with Ivar of Unleash_ — Console](https://console.substack.com/p/console-42)
- [_Unleash your features gradually_](http://ivarconr.github.io/feature-toggles-presentation/sch-dev-lunch-2017/#1 ' '), slideshow/presentation by Ivar, the creator of Unleash
