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Alex Spinov
Alex Spinov

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PostHog Has a Free Product Analytics Platform — Track Events, Funnels, and Feature Flags Without Sending Data to Third Parties

#posthog #analytics #opensource #webdev

Why PostHog?

PostHog is open-source product analytics you can self-host. Event tracking, funnels, session recordings, feature flags, A/B tests — all in one tool, no data leaving your servers.

Quick Start 

npm install posthog-js
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import posthog from 'posthog-js'

posthog.init('YOUR_API_KEY', { api_host: 'https://app.posthog.com' })

// Track events
posthog.capture('button_clicked', { button_name: 'signup', page: '/pricing' })

// Identify users
posthog.identify('user_123', { email: 'user@example.com', plan: 'pro' })
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Feature Flags 

if (posthog.isFeatureEnabled('new-checkout-flow')) {
  renderNewCheckout()
} else {
  renderOldCheckout()
}

// With payloads
const config = posthog.getFeatureFlagPayload('pricing-test')
// { price: 29, currency: 'USD', show_discount: true }
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React SDK 

import { PostHogProvider, useFeatureFlagEnabled } from 'posthog-js/react'

function App() {
  return (
    <PostHogProvider client={posthog}>
      <MyComponent />
    </PostHogProvider>
  )
}

function MyComponent() {
  const showNewUI = useFeatureFlagEnabled('new-ui')
  return showNewUI ? <NewUI /> : <OldUI />
}
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Self-Host with Docker 

git clone https://github.com/PostHog/posthog.git
cd posthog
docker compose -f docker-compose.hobby.yml up
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PostHog vs Alternatives

Feature PostHog Mixpanel Amplitude
Self-host Yes No No
Feature flags Yes No Yes
Session replay Yes No Yes
Free tier 1M events 20K users 10M events
Open source Yes No No

Need to extract data from any website at scale? I build custom web scrapers — 77 production scrapers running on Apify Store. Email me at spinov001@gmail.com for a tailored solution.

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