Flags-Kit

Type-safe feature flags for TypeScript and React.

What It Is

flags-kit is a code-first feature flag system.

You define:

• context types
• segments
• flags

Then you evaluate them in process through the current adapter and consume them through the React SDK.

For most React apps, @flagkit/react is the only package you need to install directly.

Packages

Package	Purpose
@flagkit/core	Types plus createFlag and createSegment
@flagkit/internal-adapter	In-process evaluator (segments, rollouts, conditions)
@flagkit/react	React bindings for your app
@flagkit/web-sdk	Browser SDK — backend evaluates, segments stay private
@flagkit/node-sdk	Node.js SDK — fetches flags+segments, evaluates client-side

Install

pnpm add @flagkit/react

Flow (React / Web)

1. Define your app context.
2. Define reusable segments.
3. Define flags.
4. Create the React SDK.
5. Use useFlag and useSetContext in components.

Start Here

• Getting Started
• Concepts
• React SDK
• Adapters
• Example App
• Evaluation