Cloudflare Flagship

Flagship is Cloudflare's feature flag platform. This repository contains the official Flagship SDKs for application developers who want to evaluate feature flags through OpenFeature.

The TypeScript SDK is recommended for most use cases. It supports HTTP evaluation, browser-side caching, and the native Flagship Workers binding — which skips HTTP entirely and requires no auth token configuration. If you are building on Cloudflare Workers, use the TypeScript SDK with the Workers binding. The Python and Go SDKs are available for server-side applications and support HTTP evaluation only.

SDKs

SDK	Package	Runtime	Evaluation modes	Docs
TypeScript	@cloudflare/flagship	Node.js, Cloudflare Workers, browsers	Workers binding, HTTP, browser prefetch cache	sdks/typescript
Python	cloudflare-flagship	Python server applications	HTTP	sdks/python
Go	github.com/cloudflare/flagship/sdks/go	Go server applications	HTTP	sdks/go

TypeScript

Install the SDK with the OpenFeature package for your runtime:

npm install @cloudflare/flagship @openfeature/server-sdk

Cloudflare Workers should use the Flagship binding when possible. It avoids HTTP overhead and does not require application-managed auth tokens.

import { OpenFeature } from '@openfeature/server-sdk';
import { FlagshipServerProvider, type FlagshipBinding } from '@cloudflare/flagship/server';

export default {
	async fetch(request: Request, env: { FLAGS: FlagshipBinding }) {
		await OpenFeature.setProviderAndWait(new FlagshipServerProvider({ binding: env.FLAGS }));

		const client = OpenFeature.getClient();
		const enabled = await client.getBooleanValue('dark-mode', false, {
			targetingKey: 'user-123',
		});

		return Response.json({ enabled });
	},
};

For Node.js or other server environments, use HTTP mode:

import { OpenFeature } from '@openfeature/server-sdk';
import { FlagshipServerProvider } from '@cloudflare/flagship/server';

await OpenFeature.setProviderAndWait(
	new FlagshipServerProvider({
		appId: 'your-app-id',
		accountId: 'your-account-id',
		authToken: 'your-token',
	}),
);

const client = OpenFeature.getClient();
const enabled = await client.getBooleanValue('dark-mode', false, {
	targetingKey: 'user-123',
	plan: 'premium',
});

Python

Install with uv or pip:

uv add cloudflare-flagship
# or
pip install cloudflare-flagship

from openfeature import api
from openfeature.evaluation_context import EvaluationContext
from flagship import FlagshipServerProvider

api.set_provider(
	FlagshipServerProvider(
		app_id='your-app-id',
		account_id='your-account-id',
		auth_token='your-token',
	)
)

client = api.get_client()
enabled = client.get_boolean_value(
	'dark-mode',
	False,
	EvaluationContext(targeting_key='user-123', attributes={'plan': 'premium'}),
)

The Python SDK supports HTTP evaluation only.

Go

Install with go get:

go get github.com/cloudflare/flagship/sdks/go

package main

import (
	"context"

	flagship "github.com/cloudflare/flagship/sdks/go"
	"github.com/open-feature/go-sdk/openfeature"
)

func main() {
	provider, err := flagship.NewProvider(flagship.Options{
		AppID:     "your-app-id",
		AccountID: "your-account-id",
		AuthToken: "your-token",
	})
	if err != nil {
		panic(err)
	}

	if err := openfeature.SetProviderAndWait(provider); err != nil {
		panic(err)
	}
	defer openfeature.Shutdown()

	client := openfeature.NewDefaultClient()
	enabled, err := client.BooleanValue(
		context.Background(),
		"dark-mode",
		false,
		openfeature.NewEvaluationContext("user-123", map[string]any{"plan": "premium"}),
	)
	if err != nil {
		panic(err)
	}
	_ = enabled
}

The Go SDK supports HTTP evaluation only.

Repository Layout

Path	Description
sdks/typescript	TypeScript SDK source, tests, examples, and package metadata
sdks/python	Python SDK source, tests, examples, and package metadata
sdks/go	Go SDK source, tests, examples, and module metadata
.changeset	Release intent files and Changesets configuration
.github/workflows	Pull request checks and publish workflows

Development

This is a pnpm monorepo. Node.js 22+ and pnpm 10+ are required.

pnpm install
pnpm run check

Links

• TypeScript examples
• Python examples
• Go examples
• OpenFeature specification
• Issues

License

Apache-2.0