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.claude/skills/integration-astro-view-transitions/SKILL.md

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+---
+name: integration-astro-view-transitions
+description: PostHog integration for Astro with ClientRouter view transitions
+metadata:
+  author: PostHog
+  version: 1.21.1
+---
+
+# PostHog integration for Astro (View Transitions)
+
+This skill helps you add PostHog analytics to Astro (View Transitions) applications.
+
+## Workflow
+
+Follow these steps in order to complete the integration:
+
+1. `basic-integration-1.0-begin.md` - PostHog Setup - Begin ← **Start here**
+2. `basic-integration-1.1-edit.md` - PostHog Setup - Edit
+3. `basic-integration-1.2-revise.md` - PostHog Setup - Revise
+4. `basic-integration-1.3-conclude.md` - PostHog Setup - Conclusion
+
+## Reference files
+
+- `references/EXAMPLE.md` - Astro (View Transitions) example project code
+- `references/astro.md` - Astro - docs
+- `references/identify-users.md` - Identify users - docs
+- `references/basic-integration-1.0-begin.md` - PostHog setup - begin
+- `references/basic-integration-1.1-edit.md` - PostHog setup - edit
+- `references/basic-integration-1.2-revise.md` - PostHog setup - revise
+- `references/basic-integration-1.3-conclude.md` - PostHog setup - conclusion
+
+The example project shows the target implementation pattern. Consult the documentation for API details.
+
+## Key principles
+
+- **Environment variables**: Always use environment variables for PostHog keys. Never hardcode them.
+- **Minimal changes**: Add PostHog code alongside existing integrations. Don't replace or restructure existing code.
+- **Match the example**: Your implementation should follow the example project's patterns as closely as possible.
+
+## Framework guidelines
+
+- Always use the is:inline directive on PostHog script tags to prevent Astro from processing them and causing TypeScript errors
+- Use PUBLIC_prefix for client-side environment variables in Astro (e.g., PUBLIC_POSTHOG_PROJECT_TOKEN)
+- Create a posthog.astro component in src/components/ for reusable initialization across pages
+- Import the PostHog component in a Layout and wrap all pages with that layout
+- Wrap PostHog initialization with a window.__posthog_initialized guard to prevent stack overflow during soft navigation
+- Set capture_pageview option to 'history_change' for automatic pageview tracking during soft navigation
+- Use the astro page-load event instead of just DOMContentLoaded to re-run scripts after soft navigation
+- When a reverse proxy is configured, both /static/*AND /array/* must route to the assets origin (us-assets.i.posthog.com or eu-assets.i.posthog.com).
+
+## Identifying users
+
+Identify users during login and signup events. Refer to the example code and documentation for the correct identify pattern for this framework. If both frontend and backend code exist, pass the client-side session and distinct ID using `X-POSTHOG-DISTINCT-ID` and `X-POSTHOG-SESSION-ID` headers to maintain correlation.
+
+## Error tracking
+
+Add PostHog error tracking to relevant files, particularly around critical user flows and API boundaries.