Before you start

This quickstart assumes you already:

• installed the SDK
• have a valid API Key
• created at least one project and one environment in the dashboard

If you have not done that yet, go back to Installation.

1. Initialize the client

Create an API Key in Settings -> API Keys and initialize the SDK:

import { CanaryGate } from '@canarygate/sdk/js/client'
 
const canary = new CanaryGate('cg_your_api_key')
 
try {
  await canary.init()
} catch (error) {
  console.error('Failed to initialize CanaryGate', error)
}

init() performs the initial flag fetch and caches the snapshot. For real-time updates, use the server entry (@canarygate/sdk/js/server) with stream: true. If init() fails, your application should decide whether to continue with a local fallback, temporarily disable the feature, or show an operational message.

2. Evaluate a flag with a safe fallback

const flag = canary.getFlag('new-checkout')
 
if (!flag) {
  // the flag does not exist yet, the key is wrong, or init failed
}
 
if (flag?.enabled ?? false) {
  // new checkout
} else {
  // current checkout
}

Use flag?.enabled ?? false when you want a safe fallback to the off state. This prevents the application from breaking when the flag does not exist yet or when the initial load did not finish as expected.

3. Disconnect when it makes sense

// In an SPA: during component cleanup / before unmount
canary.disconnect()

In traditional client applications, you will usually keep the connection open for the lifetime of the session. In scripts, jobs, and short-lived processes, close it explicitly when you no longer need updates.

Next steps

• Create your first flag in the dashboard
• Understand flag types
• See more complete initialization patterns