React SDK

Reference guide for integrating feature flags into React applications.

Provider setup

Mount `FlagProvider` once at app root. Reuse a single client instance per app runtime.

TSTypeScript

import { FlagProvider, useFeatureFlag, useFlagClient } from "react-featureflags";

function Example() {
  const enabled = useFeatureFlag("new-dashboard", false, { key: "user-123" });
  const client = useFlagClient();
  return enabled ? <DashboardV2 /> : <DashboardV1 />;
}

Hooks

`useFeatureFlag(flagKey, defaultValue, context)`
`useFlagsReady()`
`useAllFlags(context?)`
`useFlagClient()`

Usage patterns

Gate routes/components with default-safe fallbacks.
Use shared context builders to keep targeting attributes consistent.
Emit exposure callbacks only where analytics ownership is clear.

SSR notes

For SSR frameworks, prefer deterministic defaults during server render and re-evaluate on hydration.