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Ahnhyeongkyu
Ahnhyeongkyu

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I Built a Sub-5KB Testimonial Widget Because Every Alternative Tanked My Lighthouse Score

Every testimonial widget I tried added 200-500KB to my pages. My Lighthouse scores dropped. My ads got more expensive because pages loaded slower.

So I built Trustfolio — a testimonial platform where the entire embed widget is under 5KB gzipped.

The Problem

Most testimonial tools treat performance as an afterthought. They load heavy JavaScript bundles, inject their own CSS that conflicts with yours, and add hundreds of milliseconds to your page load.

Research shows each second of delay reduces conversions by 4.42%. If you're running paid ads, slow pages = wasted ad spend.

What I Built

Trustfolio is a full testimonial management platform:

  • Collect: Shareable collection pages (text + video, no sign-up needed for customers)
  • Analyze: AI-powered sentiment analysis, theme detection, and highlight suggestions using Claude Haiku
  • Display: 5 widget layouts — Wall, Carousel, Badge, Popup, Marquee
  • Track: Conversion tracking to see which testimonials actually drive sign-ups

The embed widget uses Shadow DOM for zero CSS conflicts and loads in under 10ms from CDN.

Tech Stack

  • Next.js + React
  • Drizzle ORM + Neon PostgreSQL (serverless)
  • Clerk Auth (GitHub + Google + Email)
  • Claude Haiku API for AI analysis
  • Shadow DOM embed widget (3.1KB gzipped)
  • Vercel deployment

Try It

Trustfolio is live with a generous free tier — 15 testimonials, 1 widget, full AI analysis. No credit card required.

Check it out: trustfolio.dev

I'd love to hear your feedback!

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