Feature flag filters

Signals can filter sessions by feature flag values. Use this to compare a release, experiment, or rollout against the rest of your traffic.

How it works

Lucent reads evaluated flag values from session metadata. Values can come from:

Lucent SDK user properties
replay integrations that export feature flag metadata
imported session metadata added by your application or provider

Lucent filters on the value attached to the session.

Send flags with the Lucent SDK

Pass evaluated flag values into Lucent as user properties.

React
Vanilla JS

<LucentIdentify
  userId={user?.id}
  email={user?.email}
  properties={{
    featureFlags: {
      "new-checkout-flow": flags.newCheckoutFlow,
      "pricing-page-redesign": flags.pricingPageRedesign,
      "paywall-test": flags.paywallTest,
    },
  }}
/>

tracker.identify({
  id: "user_123",
  email: "[email protected]",
  properties: {
    featureFlags: {
      "new-checkout-flow": launchDarkly.variation("new-checkout-flow"),
      "pricing-page-redesign": statsig.checkGate("pricing-page-redesign"),
      "paywall-test": growthbook.getFeatureValue("paywall-test", "control"),
    },
  },
});

Filter in Signals

Signal filters define a cohort for an individual Signal. They are separate from the project-level processing controls under Settings → Filtering.

Open Signals

Go to Signals in the Lucent dashboard.

Add a feature flag filter

Choose a flag key and value, such as new-checkout-flow = variant-a.

Compare sessions

Review sessions and issues from the selected flag cohort.

Get started

Browser SDK

Mobile SDK

Integrations

Configure Lucent

Signals

MCP

AI tools

Feature flag filters

How it works

Send flags with the Lucent SDK

Filter in Signals

​How it works

​Send flags with the Lucent SDK

​Filter in Signals

How it works

Send flags with the Lucent SDK

Filter in Signals