Dynamic configuration for React applications.
Replane is a dynamic configuration manager that lets you tweak your software without running scripts or building your own admin panel. Store feature flags, rate limits, UI text, log level, rollout percentage, and more. Delegate editing to teammates and share config across services. No redeploys needed.
- Feature flags – toggle features, run A/B tests, roll out to user segments
- Operational tuning – adjust limits, TTLs, and timeouts without redeploying
- Per-environment settings – different values for production, staging, dev
- Incident response – instantly revert to a known-good version
- Cross-service configuration – share settings with realtime sync
- Non-engineer access – safe editing with schema validation
npm install @replanejs/react
# or
pnpm add @replanejs/react
# or
yarn add @replanejs/react- React 18.0.0 or higher
- Node.js 18.0.0 or higher
import { ReplaneProvider, useConfig } from "@replanejs/react";
function App() {
return (
<ReplaneProvider
connection={{
baseUrl: "https://cloud.replane.dev", // or your self-hosted URL
sdkKey: "your-sdk-key",
}}
loader={<div>Loading...</div>}
>
<MyComponent />
</ReplaneProvider>
);
}
function MyComponent() {
const isFeatureEnabled = useConfig<boolean>("feature-flag-name");
return <div>{isFeatureEnabled ? "Feature is enabled!" : "Feature is disabled"}</div>;
}Provider component that makes the Replane client available to your component tree. Supports multiple usage patterns:
The provider creates and manages the client internally. Use an Error Boundary to handle initialization errors:
import { ErrorBoundary } from "react-error-boundary";
<ErrorBoundary fallback={<div>Failed to load configuration</div>}>
<ReplaneProvider
connection={{
baseUrl: "https://your-replane-server.com",
sdkKey: "your-sdk-key",
}}
loader={<LoadingSpinner />}
>
<App />
</ReplaneProvider>
</ErrorBoundary>;| Prop | Type | Required | Description |
|---|---|---|---|
connection |
ConnectOptions | null |
Yes | Connection options (see below), or null to skip connection |
defaults |
Record<string, unknown> |
No | Default values if server is unavailable |
context |
Record<string, unknown> |
No | Default context for override evaluations |
snapshot |
ReplaneSnapshot |
No | Snapshot for SSR hydration |
logger |
ReplaneLogger |
No | Custom logger (default: console) |
loader |
ReactNode |
No | Component to show while loading |
suspense |
boolean |
No | Use React Suspense for loading state |
async |
boolean |
No | Connect asynchronously (renders immediately with defaults) |
The connection prop accepts the following options:
| Option | Type | Required | Description |
|---|---|---|---|
baseUrl |
string |
Yes | Replane server URL |
sdkKey |
string |
Yes | SDK key for authentication |
connectTimeoutMs |
number |
No | SDK connection timeout (default: 5000) |
requestTimeoutMs |
number |
No | Timeout for SSE requests (default: 2000) |
retryDelayMs |
number |
No | Base delay between retries (default: 200) |
inactivityTimeoutMs |
number |
No | SSE inactivity timeout (default: 30000) |
fetchFn |
typeof fetch |
No | Custom fetch implementation |
See @replanejs/sdk documentation for more details.
Use this when you need more control over client lifecycle:
import { Replane } from "@replanejs/sdk";
const client = new Replane();
await client.connect({
baseUrl: "https://your-replane-server.com",
sdkKey: "your-sdk-key",
});
<ReplaneProvider client={client}>
<App />
</ReplaneProvider>;Integrates with React Suspense for loading states:
<ErrorBoundary fallback={<div>Failed to load configuration</div>}>
<Suspense fallback={<LoadingSpinner />}>
<ReplaneProvider
connection={{
baseUrl: "https://cloud.replane.dev", // or your self-hosted URL
sdkKey: "your-sdk-key",
}}
suspense
>
<App />
</ReplaneProvider>
</Suspense>
</ErrorBoundary>Connect in the background while rendering immediately with defaults:
<ReplaneProvider
connection={{
baseUrl: "https://your-replane-server.com",
sdkKey: "your-sdk-key",
}}
defaults={{ featureEnabled: false }}
async
>
<App />
</ReplaneProvider>Restore a client from a snapshot obtained on the server. This is synchronous and useful for SSR scenarios:
// On the server
const serverClient = new Replane();
await serverClient.connect({ baseUrl: "...", sdkKey: "..." });
const snapshot = serverClient.getSnapshot();
// Pass snapshot to client via props, context, or serialized HTML
// On the client
<ReplaneProvider
connection={{
baseUrl: "https://your-replane-server.com",
sdkKey: "your-sdk-key",
}}
snapshot={snapshot}
>
<App />
</ReplaneProvider>;The restored client is immediately available with no loading state. The provider will establish a connection for real-time updates in the background.
Hook to retrieve a configuration value. Automatically subscribes to updates and re-renders when the value changes.
function MyComponent() {
// Basic usage
const theme = useConfig<string>("theme");
// With evaluation context
const discount = useConfig<number>("discount-percentage", {
context: {
userId: "123",
isPremium: true,
},
});
return (
<div>
Theme: {theme}, Discount: {discount}%
</div>
);
}Hook to access the underlying Replane client directly. Returns the client instance:
function MyComponent() {
const replane = useReplane();
const handleClick = () => {
// Access replane methods directly
const value = replane.get("some-config");
console.log(value);
};
return <button onClick={handleClick}>Get Config</button>;
}Factory function to create a typed version of useReplane. Returns a hook that provides the typed client directly:
import { createReplaneHook } from "@replanejs/react";
// Define your config types
interface AppConfigs {
theme: { darkMode: boolean; primaryColor: string };
features: { beta: boolean; analytics: boolean };
maxItems: number;
}
// Create a typed hook
const useAppReplane = createReplaneHook<AppConfigs>();
function MyComponent() {
const replane = useAppReplane();
// replane.get is now typed - autocomplete works!
const theme = replane.get("theme");
// ^? { darkMode: boolean; primaryColor: string }
return <div>Dark mode: {theme.darkMode ? "on" : "off"}</div>;
}Factory function to create a typed version of useConfig. This provides autocomplete for config names and type inference for values:
import { createConfigHook } from "@replanejs/react";
// Define your config types
interface AppConfigs {
theme: { darkMode: boolean; primaryColor: string };
features: { beta: boolean; analytics: boolean };
maxItems: number;
}
// Create a typed hook
const useAppConfig = createConfigHook<AppConfigs>();
function MyComponent() {
// Autocomplete for config names, automatic type inference
const theme = useAppConfig("theme");
// ^? { darkMode: boolean; primaryColor: string }
const features = useAppConfig("features");
// ^? { beta: boolean; analytics: boolean }
const maxItems = useAppConfig("maxItems");
// ^? number
// With context override
const premiumFeatures = useAppConfig("features", {
context: { userId: "123", plan: "premium" },
});
return (
<div>
<p>Dark mode: {theme.darkMode ? "on" : "off"}</p>
<p>Beta enabled: {features.beta ? "yes" : "no"}</p>
<p>Max items: {maxItems}</p>
</div>
);
}Utility function to clear the suspense cache. Useful for testing or forcing re-initialization:
import { clearSuspenseCache } from "@replanejs/react";
// Clear cache for specific options
clearSuspenseCache({
baseUrl: "https://your-replane-server.com",
sdkKey: "your-sdk-key",
});
// Clear entire cache
clearSuspenseCache();The SDK is fully typed. For the best TypeScript experience, use the hook factory functions:
// Define all your config types in one interface
interface AppConfigs {
"theme-config": {
darkMode: boolean;
primaryColor: string;
};
"feature-flags": {
newUI: boolean;
beta: boolean;
};
"max-items": number;
"welcome-message": string;
}
// Create typed hooks once
const useAppReplane = createReplaneHook<AppConfigs>();
const useAppConfig = createConfigHook<AppConfigs>();
// Use throughout your app with full type safety
function Settings() {
const theme = useAppConfig("theme-config");
// ^? { darkMode: boolean; primaryColor: string }
const replane = useAppReplane();
const snapshot = replane.getSnapshot();
// ^? { configs: ConfigSnapshot<AppConfigs>[] }
return (
<div style={{ color: theme.primaryColor }}>
Dark mode: {theme.darkMode ? "enabled" : "disabled"}
</div>
);
}The provider throws errors during rendering so they can be caught by React Error Boundaries:
import { Component, ReactNode } from "react";
class ErrorBoundary extends Component<
{ children: ReactNode; fallback: ReactNode },
{ hasError: boolean }
> {
state = { hasError: false };
static getDerivedStateFromError() {
return { hasError: true };
}
render() {
if (this.state.hasError) {
return this.props.fallback;
}
return this.props.children;
}
}
// Usage
<ErrorBoundary fallback={<div>Configuration failed to load</div>}>
<ReplaneProvider connection={connection} loader={<Loading />}>
<App />
</ReplaneProvider>
</ErrorBoundary>;Or use a library like react-error-boundary:
import { ErrorBoundary } from "react-error-boundary";
<ErrorBoundary
fallbackRender={({ error, resetErrorBoundary }) => (
<div>
<p>Error: {error.message}</p>
<button onClick={resetErrorBoundary}>Retry</button>
</div>
)}
onReset={() => clearSuspenseCache()}
>
<ReplaneProvider connection={connection} loader={<Loading />}>
<App />
</ReplaneProvider>
</ErrorBoundary>;Have questions or want to discuss Replane? Join the conversation in GitHub Discussions.
MIT