PostHog

PostHog is an all-in-one, open-source product analytics platform that combines everything a product team needs in a single self-hostable tool: event tracking, funnels, retention charts, session recording, heatmaps, feature flags, A/B testing, and a data warehouse — with no need to stitch together Mixpanel, FullStory, LaunchDarkly, and Optimizely.

Market opportunity

The product analytics market exceeds $12B annually and is deeply fragmented. A typical growth-stage startup pays $500–$2,000/month for Mixpanel or Amplitude (analytics), $200–$500/month for FullStory or Hotjar (session replay), $150–$500/month for LaunchDarkly (feature flags), and another $500–$2,000/month for an A/B testing tool. PostHog consolidates all four categories into one self-hostable platform — the savings are $10,000–$60,000/year for a mid-size team. As companies increasingly want to own their user data (privacy regulations, AI training implications), self-hosted product analytics is a market that's actively growing.

Technical overview

• Stack: Python/Django backend, ClickHouse for analytics queries, PostgreSQL for metadata, Redis for queues; deploys on Docker or Kubernetes.
• Event capture: JavaScript, React, React Native, iOS, Android, Python, Go, Ruby, and Node.js SDKs.
• Analytics: funnels, retention, user paths, cohorts, dashboards, and SQL access to raw events.
• Session replay: full session recordings with console logs, network activity, and rage-click detection.
• Feature flags: multi-variate flags with gradual rollouts, user targeting, and local evaluation for zero-latency.
• A/B testing: experiment framework with statistical significance tracking tied directly to your analytics events.

Who's it for

Product teams who want all their tools in one place and their data on their own infrastructure, startups replacing 4 expensive SaaS tools with one open-source platform, and companies with GDPR or data-residency requirements for user behavioral data.

Get started

PostHog Cloud (generous free tier — 1M events/month free): Sign up at app.posthog.com, create a project, and add the snippet to your app:

posthog.init('your-api-key', { api_host: 'https://app.posthog.com' })

Events start flowing immediately. Enable session recording in Project Settings → Session Recording.

Self-host (Docker — for larger teams):

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/posthog/posthog/HEAD/bin/deploy-hobby)"

This one-line script provisions a self-hosted PostHog on your server with ClickHouse, PostgreSQL, and all services. Recommended: 4 vCPU, 8 GB RAM minimum for production use. Point your SDK at your own hostname.