Getting started

Browser#

npm install @fernohq/analytics-next

import { AnalyticsBrowser } from '@fernohq/analytics-next'

export const analytics = AnalyticsBrowser.load({
  writeKey: import.meta.env.VITE_FERNO_WRITE_KEY,
})

analytics.track('Opened pricing page', { source: 'navigation' })

The browser key is intended for client-side use. Do not put a secret server credential in browser code.

Node#

npm install @fernohq/analytics-node

import { Analytics } from '@fernohq/analytics-node'

const analytics = new Analytics({ writeKey: process.env.FERNO_WRITE_KEY! })
analytics.track({
  userId: 'user-123',
  event: 'Completed checkout payment',
  properties: { plan: 'pro', currency: 'USD' },
})
await analytics.closeAndFlush()

Keep Node keys in environment variables or a secrets manager.

First instrumentation checklist#

1. Write the business question the events should answer.
2. Define an event dictionary with stable names and descriptions.
3. Track behavior and outcomes, not form values or free text.
4. Add identify after authentication.
5. Add server-confirmed events for payment and subscription outcomes.
6. Review payloads for confidential information before production.

pnpm build

Deploy the generated dist/client directory to your static host.