# Flags SDK 3\.0

**Published:** January 16, 2025 | **Authors:** Dominik Ferber, Andy Schneider, Aaron Morris

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The [Flags SDK](https://flags-sdk.dev/) is a library that gives developers tools to use feature flags in Next.js and SvelteKit applications.

The Flags SDK version 3.0 adds:

- Pages Router support so feature flags can be used in App Router and Pages Router
- New adapters architecture that allows the SDK to integrate with various data sources and feature flag providers
- A new `identify` concept that allows you to establish an evaluation context for your feature flags. With this addition, you can tailor flags and experiments for individual users or groups

```tsx
import { flag } from 'flags/next';
export const exampleFlag = flag({
  key: 'example-flag',
  decide() {
    return false;
  },
});
```

With this release, [the repository](https://github.com/vercel/flags) is now open source and under the MIT License, providing more transparency and allowing for community contributions and integrations.

Check out the [new Flags SDK documentation](https://www.flags-sdk.dev/) with updated examples to learn more.

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📚 **More updates:** [View all changelog entries](/changelog/sitemap.md) | [Blog](/blog/sitemap.md)