vercel-marketing-analytics

name: vercel-marketing-analytics description: > Design and implement a complete Vercel Analytics custom event tracking strategy for marketing sites. Use this skill whenever a user wants to track user journeys, conversions, funnels, CTAs, lead gen, or engagement on a marketing site using Vercel Analytics. Triggers include: "track user journeys", "analytics for my marketing site", "conversion tracking", "funnel analytics", "track CTA clicks", "measure marketing performance", or any request to instrument a Next.js/Vercel landing page with meaningful analytics. Always use this skill — even if the user only mentions one of these concepts — since producing a coherent tracking plan requires both marketing strategy and correct Vercel Analytics implementation knowledge.

Vercel Marketing Analytics

Expert in both conversion-focused marketing and Vercel Web Analytics. Design a complete, opinionated event tracking strategy for marketing sites, then produce production-ready implementation code.

Workflow

Phase 1: Understand the Site & Goals

Before writing any code, ask (or infer from context):

1. Primary conversion goal? (lead capture, demo request, signup, purchase)
2. Framework? (Next.js App Router, Pages Router, Remix, SvelteKit, Nuxt, HTML)
3. Sections/pages? (hero, pricing, features, testimonials, blog, contact)
4. CTAs? (buttons, forms, links — labels and locations)
5. Existing analytics? (don't duplicate; complement GA4/Segment if present)

If the user provides a site or component, infer answers from the code.

Phase 2: Build the Event Taxonomy

Design events across three funnel layers. See references/event-taxonomy.md for the full taxonomy template with all event tables.

Three layers:

• Layer 1 — Awareness (TOFU): Page views, hero CTA clicks, nav interactions, UTM capture
• Layer 2 — Consideration (MOFU): Section views, pricing engagement, testimonials, FAQ, video, demo requests
• Layer 3 — Conversion (BOFU): Form started → submitted → error, signup completed, purchase completed, outbound links

Key principle: Track intent (click) separately from completion (server confirm) to reveal drop-off.

Phase 3: Implementation

Ensure @vercel/analytics >= 1.1.0:

npm install @vercel/analytics@latest

Client-Side Events

import { track } from '@vercel/analytics';

CTA Button pattern:

import { track } from '@vercel/analytics';

interface CTAButtonProps {
  label: string;
  section: string;
  href?: string;
  variant?: 'primary' | 'secondary';
  onClick?: () => void;
}

export function CTAButton({ label, section, href, variant = 'primary', onClick }: CTAButtonProps) {
  const handleClick = () => {
    track('CTA Clicked', { label, section, variant, destination: href ?? 'modal' });
    onClick?.();
  };

  return href
    ? <a href={href} onClick={handleClick}>{label}</a>
    : <button onClick={handleClick}>{label}</button>;
}

Form funnel pattern (Start → Submit → Error):

import { track } from '@vercel/analytics';
import { useRef } from 'react';

export function LeadForm({ formId, formName }: { formId: string; formName: string }) {
  const hasStarted = useRef(false);

  const handleFirstFocus = () => {
    if (hasStarted.current) return;
    hasStarted.current = true;
    track('Form Started', { form_id: formId, form_name: formName });
  };

  const handleSubmit = async (e: React.FormEvent<HTMLFormElement>) => {
    e.preventDefault();
    track('Form Submitted', { form_id: formId, form_name: formName });
  };

  return (
    <form onSubmit={handleSubmit}>
      <input type="email" onFocus={handleFirstFocus} placeholder="Email" />
      <button type="submit">Get Started</button>
    </form>
  );
}

Scroll-into-view section tracking:

import { track } from '@vercel/analytics';
import { useEffect, useRef } from 'react';

export function useSectionTracking(sectionName: string, position: number) {
  const ref = useRef<HTMLElement>(null);
  const tracked = useRef(false);

  useEffect(() => {
    const el = ref.current;
    if (!el) return;
    const observer = new IntersectionObserver(
      ([entry]) => {
        if (entry.isIntersecting && !tracked.current) {
          tracked.current = true;
          track('Section Viewed', { section_name: sectionName, position });
        }
      },
      { threshold: 0.4 }
    );
    observer.observe(el);
    return () => observer.disconnect();
  }, [sectionName, position]);

  return ref;
}

UTM parameter capture (root layout):

'use client';
import { track } from '@vercel/analytics';
import { useSearchParams } from 'next/navigation';
import { useEffect } from 'react';

export function UTMCapture() {
  const params = useSearchParams();

  useEffect(() => {
    const utm_source = params.get('utm_source');
    if (utm_source) {
      track('Campaign Visit', {
        utm_source,
        utm_medium: params.get('utm_medium') ?? 'none',
        utm_campaign: params.get('utm_campaign') ?? 'none',
      });
    }
  }, []);

  return null;
}

Server-Side Events (authoritative conversions)

Use @vercel/analytics/server for events that must be trusted (signups, purchases) — immune to ad blockers.

// App Router server action
'use server';
import { track } from '@vercel/analytics/server';

export async function signupAction(formData: FormData) {
  const plan = formData.get('plan') as string;
  // ... create user in DB
  await track('Signup Completed', { plan, source: 'marketing_site' });
}

// Pages Router API route
import type { NextApiRequest, NextApiResponse } from 'next';
import { track } from '@vercel/analytics/server';

export default async function handler(req: NextApiRequest, res: NextApiResponse) {
  // ... process payment
  await track('Purchase Completed', {
    product: req.body.product,
    price: req.body.price,
    currency: 'USD',
  });
  res.status(200).json({ success: true });
}

Phase 4: Dashboard Setup

After deploying, instruct the user to:

1. Go to Vercel Dashboard → [Project] → Analytics → Events
2. Key funnels to examine:
   • Form Started → Form Submitted → Signup Completed (lead gen)
   • Hero CTA Clicked → Demo Requested → Signup Completed (demo)
   • Campaign Visit → CTA Clicked → Signup Completed (campaign ROI)
3. Filter by utm_source for channel performance
4. Filter CTA Clicked by section for highest-converting sections

Phase 5: Event Naming Conventions

Limitations

• Custom event properties are plan-limited (check Vercel Analytics pricing)
• No nested objects in custom data
• Server-side uses @vercel/analytics/server — different import than client
• Ad blockers may suppress client-side events — use server-side for critical conversions
• Event names and values capped at 255 characters

References

• references/event-taxonomy.md — Full event taxonomy tables for all three funnel layers
• references/marketing-funnel-patterns.md — TOFU/MOFU/BOFU patterns with example event maps