[CI] (3864784) next-js/15-pages-router-saas

[wizard-ci-bot]

Automated wizard CI run

Source: manual
Trigger ID: 3864784
App: next-js/15-pages-router-saas
App directory: apps/next-js/15-pages-router-saas
Workbench branch: wizard-ci-3864784-next-js-15-pages-router-saas
Wizard branch: main
Examples branch: main
PostHog (MCP) branch: master
Timestamp: 2026-01-21T22:28:40.526Z
Duration: 545.2s

[wizard-ci-bot]

Now I have all the information I need. Let me write the comprehensive PR evaluation report.

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PR Evaluation Report

Summary

This PR integrates PostHog analytics into a Next.js 15 Pages Router SaaS application. It adds both client-side (posthog-js) and server-side (posthog-node) SDKs, implements a reverse proxy for ad-blocker circumvention, and adds comprehensive event tracking across authentication flows, subscription management, and team operations.

Files changed	Lines added	Lines removed
18	+694	-4

Confidence score: 4/5 👍

• Client-side PostHog initialization may not load correctly: The instrumentation-client.ts file relies on Next.js 15's client instrumentation feature, but this is primarily designed for App Router. For Pages Router, PostHog should be initialized in _app.tsx or via a provider component to ensure it loads on all pages. [MEDIUM]
• Server-side events not flushed before response: The posthog-node capture calls are fire-and-forget without awaiting posthog.flush(). In serverless environments, events may be lost if the function terminates before the async buffer flushes. [MEDIUM]
• Duplicate event tracking on client and server: Sign-in/sign-up events are captured both client-side (login.tsx) and server-side (sign-in.ts, sign-up.ts) with slightly different event names (user_logged_in vs user_signed_in), which could cause analytics confusion. [LOW]

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File changes

Filename	Score	Description
instrumentation-client.ts	3/5	New file for PostHog client init. Uses Next.js 15 instrumentation pattern which may not work correctly with Pages Router.
lib/posthog-server.ts	4/5	Clean singleton pattern for server-side PostHog client. Uses aggressive flush settings (flushAt: 1, flushInterval: 0).
next.config.ts	5/5	Correctly implements reverse proxy rewrites for PostHog to circumvent ad blockers.
package.json	5/5	Adds posthog-js and posthog-node dependencies with appropriate versions.
components/header.tsx	5/5	Clean integration of sign-out tracking with posthog.reset() call.
components/login.tsx	4/5	Adds user identification and event capture, but duplicates server-side events.
pages/api/account/update.ts	4/5	Adds account_updated event and identify call. No flush await.
pages/api/auth/sign-in.ts	4/5	Comprehensive sign-in tracking with user properties. No flush await.
pages/api/auth/sign-up.ts	4/5	Tracks sign-up and invitation_accepted events. No flush await.
pages/api/stripe/checkout.ts	4/5	Tracks checkout_completed with rich subscription properties. No flush await.
pages/api/stripe/create-checkout.ts	4/5	Tracks checkout_started with plan context. No flush await.
pages/api/stripe/webhook.ts	4/5	Tracks subscription_updated and subscription_cancelled from webhooks. Uses customer ID as distinct_id which is reasonable.
pages/api/team/invite.ts	4/5	Tracks team_member_invited with relevant properties. No flush await.
pages/api/team/remove-member.ts	4/5	Tracks team_member_removed event. No flush await.
pages/dashboard/index.tsx	5/5	Adds manage_subscription_clicked event and exception capture.
pages/pricing.tsx	5/5	Tracks pricing_plan_selected with plan details and exception capture.
pnpm-lock.yaml	5/5	Lock file correctly updated with PostHog dependencies.
posthog-setup-report.md	5/5	Well-documented setup report with event inventory.

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App sanity check: 4/5 ✅

Criteria	Result	Description
App builds and runs	Yes	Build completes successfully with no errors
Preserves existing env vars & configs	Yes	Existing .env vars preserved, PostHog vars added
No syntax or type errors	Yes	TypeScript compilation succeeds
Correct imports/exports	Yes	All imports resolve correctly
Minimal, focused changes	Yes	Changes are focused on PostHog integration only

Issues

• Client instrumentation may not load in Pages Router: The instrumentation-client.ts pattern is designed for App Router. In Pages Router, this file may not be automatically loaded. Consider importing PostHog initialization in _app.tsx instead. [MEDIUM]

Other completed criteria

• Environment variables properly documented in .env
• No PII exposed in committed files
• API key uses NEXT_PUBLIC_ prefix appropriately for client-side access
• Consistent code style matching existing patterns

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PostHog implementation: 4/5 ✅

Criteria	Result	Description
PostHog SDKs installed	Yes	posthog-js@^1.333.0 and posthog-node@^5.24.1 in package.json
PostHog client initialized	Partial	Client initialized in instrumentation-client.ts, server singleton in lib/posthog-server.ts. Client init may not load for Pages Router.
capture()	Yes	14+ distinct events captured across auth, checkout, team, and subscription flows
identify()	Yes	User identification on sign-in, sign-up, and account update with email, name, role properties
Error tracking	Yes	capture_exceptions: true in client config, captureException() calls in login, dashboard, pricing
Reverse proxy	Yes	Correctly configured in next.config.ts with /ingest rewrites to us.i.posthog.com

Issues

• Client instrumentation pattern: instrumentation-client.ts is a Next.js 15 App Router feature. For Pages Router, initialize PostHog in _app.tsx or use a custom <PostHogProvider>. [MEDIUM]
• Server-side events may be lost: posthog.capture() calls are not awaited and no flush() is called before response ends. In serverless/edge environments, events may be lost. Add await posthog.flush() or use posthog.capture(...); await posthog.flush() pattern. [MEDIUM]
• Duplicate event names: Client captures user_logged_in while server captures user_signed_in for same action. Consider consistent naming. [LOW]

Other completed criteria

• API host correctly set to /ingest for reverse proxy
• ui_host set to https://us.posthog.com for toolbar/recordings
• Debug mode enabled only in development
• defaults: '2025-05-24' option included
• skipTrailingSlashRedirect: true added for PostHog API compatibility
• posthog.reset() called on sign-out

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PostHog insights and events: 5/5 ✅

Filename	PostHog events	Description
components/header.tsx	user_signed_out	Captures sign-out with reset for session tracking
components/login.tsx	user_logged_in, user_signed_up, captureException	Client-side auth events with invite tracking
pages/api/auth/sign-in.ts	user_signed_in	Server-side with team_id, subscription status
pages/api/auth/sign-up.ts	user_signed_up, invitation_accepted	Tracks invite flow separately for funnel analysis
pages/api/account/update.ts	account_updated	Tracks profile changes with identify update
pages/api/stripe/create-checkout.ts	checkout_started	Funnel entry point with plan context
pages/api/stripe/checkout.ts	checkout_completed	Conversion event with subscription details
pages/api/stripe/webhook.ts	subscription_updated, subscription_cancelled	Churn and upgrade tracking from Stripe webhooks
pages/api/team/invite.ts	team_member_invited	Team growth tracking
pages/api/team/remove-member.ts	team_member_removed	Team churn tracking
pages/dashboard/index.tsx	manage_subscription_clicked, captureException	Engagement tracking
pages/pricing.tsx	pricing_plan_selected, captureException	Pricing funnel with plan details

Issues

None - event coverage is comprehensive and well-designed.

Other completed criteria

• Events cover full user lifecycle: signup → subscription → team management → churn
• Rich properties enable segmentation (team_id, plan_name, subscription_status)
• Source property (api, stripe_webhook) enables channel analysis
• Funnel-ready events: pricing_plan_selected → checkout_started → checkout_completed
• Team analytics: team_member_invited → invitation_accepted → team_member_removed
• Error tracking integrated into critical user flows

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Reviewed by wizard workbench PR evaluator