Move fast Break nothing

Feature flags for developers who ship.

Powerful tooling · Transparent pricing · No enterprise games

Deploy anxiety is real

All-or-nothing deploys. Merge, pray, monitor. Something breaks at 5pm and you're rolling back the entire release. Your team ships monthly instead of daily because nobody wants to be the one holding the deploy.

terminal
 $ git push origin main
Deploying to production...
ERROR: /api/checkout returned 500
ERROR: 2,847 users affected
Rolling back entire release... 

Feature flags give you control

Decouple deployment from release. Ship code to production whenever you want. Roll out to 1% of users, then 10%, then everyone. Something wrong? Disable it in milliseconds. No rollback. No redeploy. No panic.

10x/day

Ship Frequency

200ms

Disable Time

Deploys to Roll Back

5 min

To First Flag

Install. Import. Ship.

5-minute integration, not 5-week onboarding. One API key, clear docs, done.

app.js
$ npm install @flipswitch-io/web-provider @openfeature/web-sdk


import { FlipswitchWebProvider } from '@flipswitch-io/web-provider'
import { OpenFeature } from '@openfeature/web-sdk'

await OpenFeature.setProviderAndWait(
  new FlipswitchWebProvider({ apiKey: 'your-api-key' })
)
const client = OpenFeature.getClient()

// Evaluate a flag
const enabled = await client.getBooleanValue(
    'new-checkout', false, { targetingKey: userId }
)
if (enabled) {
  showNewCheckout()
}
$ pip install flipswitch-sdk openfeature-sdk


from flipswitch import FlipswitchProvider
from openfeature import api

api.set_provider(
    FlipswitchProvider(api_key="your-api-key")
)
client = api.get_client()

# Evaluate a flag
ctx = EvaluationContext(targeting_key=user_id)
enabled = client.get_boolean_value("new-checkout", False, ctx)
if enabled:
    show_new_checkout()
$ go get github.com/flipswitch-io/go-sdk


import (
    "github.com/open-feature/go-sdk/openfeature"
    flipswitch "github.com/flipswitch-io/go-sdk"
)

provider, _ := flipswitch.NewProvider("your-api-key")
openfeature.SetProvider(provider)
client := openfeature.NewClient("my-app")

// Evaluate a flag
enabled, _ := client.BooleanValue(
    ctx, "new-checkout", false, openfeature.NewEvaluationContext(userId, map[string]any{}),
)
// Maven
<dependency>
  <groupId>io.flipswitch</groupId>
  <artifactId>flipswitch-sdk</artifactId>
</dependency>


var provider = FlipswitchProvider.builder("your-api-key").build();
var api = OpenFeatureAPI.getInstance();
api.setProviderAndWait(provider);
var client = api.getClient();

// Evaluate a flag
var ctx = new MutableContext(userId);
var enabled = client.getBooleanValue("new-checkout", false, ctx);
if (enabled) {
    showNewCheckout();
}

The toolkit

Gradual rollouts, experiments, targeting rules and kill switches, each with a code example.

Gradual Rollouts

Deploy to 1%. Then 10%. Then everyone. Or roll back to 0% instantly.

const enabled = await client.getBooleanValue(
  "new-checkout",
  false,         // default: off
  { targetingKey: userId }
)
// true for ~10% of users, false for the rest

A/B Testing

Measure before you commit. Compare metrics. Make decisions with data.

const variant = await client.getStringValue(
  "checkout-experiment",
  "control",
  { targetingKey: userId }
)
// "control" | "variant-a" | "variant-b"

Targeting

Show new features to your team first. Or that enterprise customer. Or users in EU.

await client.getBooleanValue(
  "beta-feature",
  false,
  {
    targetingKey: userId,
    team: "engineering",
    region: "eu-west-1"
  }
)

Kill Switches

Something broke? Disable the feature in 200ms. No code deploy. No panic.

const enabled = await client.getBooleanValue(
  "payments-v2",
  false,           // safe default
  { targetingKey: userId }
)
// Toggle off in dashboard → 200ms

Open Standards. Full Privacy.

Built on OpenFeature and OFREP. Switch providers without rewriting your evaluation code.

OpenFeature Native

Standard API, any provider. Flipswitch implements the OpenFeature specification and OFREP protocol. Switch providers without changing application code.

Multi-Language SDKs

First-class SDKs for every major platform. Type-safe, idiomatic, and built for each ecosystem.

JS Python Go Java .NET Rust Swift PHP Ruby

Privacy by Design

Flags are evaluated server-side, never stored, and discarded immediately after evaluation. Configuration and targeting rules stay on the server, never sent to the client. Self-host the proxy and data never leaves your infrastructure.

View on GitHub

Five minutes to your first flag.

Deploy to prod at 4pm on a Friday. Sleep soundly.

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