PostHog Instrumentation Skill

Help users add PostHog analytics, event tracking, and feature flags to their code.

When to Use

• User asks to "add PostHog" or "add analytics"
• User wants to track events or user actions
• User needs to implement feature flags
• User asks about instrumenting their code

Workflow

1. Identify the framework (React, Next.js, Python, Node.js, etc.)
2. Check for existing PostHog setup
3. Add appropriate instrumentation

Code Patterns

JavaScript/TypeScript

// Event tracking
posthog.capture("button_clicked", { button_name: "signup" });

// Feature flags
if (posthog.isFeatureEnabled("new-feature")) {
  // Show new feature
}

// User identification
posthog.identify(userId, { email: user.email });

Python

from posthog import Posthog
posthog = Posthog(api_key='<ph_project_api_key>')

# Event tracking
posthog.capture(distinct_id='user_123', event='purchase_completed')

# Feature flags
if posthog.feature_enabled('new-feature', 'user_123'):
    # Show new feature

React

import { usePostHog } from "posthog-js/react";

function MyComponent() {
  const posthog = usePostHog();

  const handleClick = () => {
    posthog.capture("button_clicked");
  };
}

Best Practices

• Use consistent event naming (snake_case recommended)
• Include relevant properties with events
• Identify users early in their session
• Use feature flags for gradual rollouts