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Targeting Options

FlagSync offers flexible ways to roll out feature flags:

All Users

Serve a variant to everyone.

User Segments

Target specific users or groups using custom attributes.

Percentage Rollouts

Distribute variants by percentage across users.

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All Users

Serve a single variant to every user, ensuring a consistent experience with default settings. This approach relies on:

  • Disabled Variant: Applied when the flag is off, serving as a fallback (e.g., “0% discount” for all).
  • Enabled Variant: Applied when the flag is on, unless overridden by targeting or rollouts (e.g., “20% discount” for all).

Defaults provide a safety net—e.g., reverting to “0% discount” during system issues.

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User Segments

Target specific users by passing custom attributes via the SDK and defining rules in the dashboard to match those attributes. For example:

  • Use Case: Create a rule to serve a beta feature to “QA Testers” and “PMs” while others see the baseline.
  • Implementation: Provide attributes in the SDK—FlagSync auto-populates the rule creation UI with these attributes for targeting.
import { FlagSyncFactory } from '@flagsync/js-sdk';

const factory = FlagSyncFactory({
  sdkKey: 'your-sdk-key',
  core: {
    key: 'user123',
    attributes: { jobTitle: 'QA Tester', isVIP: false }
  }
});

In a real app, these values (e.g., user123, QA Tester) are typically sourced from a user or session object.

Use key instead of custom to target the unique identifier (e.g., user123).

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Percentage Rollouts

Distribute variants by percentage to control rollout scope and risk. FlagSync simplifies this with:

  • Allocation: Set splits (e.g., 25% each for four variants)—must total 100%.
  • Use Case: Allow gradual releases—e.g., 10% rollout to test stability.

Users are bucketed deterministically, ensuring they receive the same variant consistently during the rollout.

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Next Steps