Blog · 2026-07-03 · 5 min

What is vibe coding? A guide to AI app builders (v0, Lovable, Bolt, Replit)

What 'vibe coding' means, the four major AI app builders, and why the sites they produce look so alike.

Vibe coding is the practice of building apps and sites by describing a 'vibe' to an AI in natural language, instead of writing every line by hand. Through 2025, tools like v0, Lovable, Bolt, and Replit went mainstream, letting people who barely code ship a working product in hours.

The four major AI app builders

v0 (Vercel)

Vercel's UI generator. It produces React/Next.js components from a prompt and deploys straight to Vercel. Component quality is high, but you tend to get locked into the Vercel ecosystem.

Lovable

A full-stack builder that generates a React frontend and a Supabase backend from one prompt. It's the go-to for non-developers who need a real database. The catch: exposed Supabase keys and RLS left off are common.

Bolt.new

Fast in-browser generation with full code access. Impressive in demos, but many reviewers note it strains under real complexity.

Replit

An online-IDE tool strong on collaboration and Python-heavy prototyping.

Why do vibe-coded sites look alike?

AI builders repeat 'safe defaults'. The result: purple-to-indigo gradients, centered heroes, and the same animation components (Beams, Spotlight, Marquee) across many products. Add copy-paste kits like Aceternity UI or Magic UI and you get 'that hero you've seen before'.

This speeds up building but makes products look mass-produced, which hurts trust and conversion. VibeCheck detects exactly these fingerprints and tells you what to change to lose the tells.

How much does your site show?

Check your stack and vibe score from a single URL.

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