GitHub

Introduction to Weldr

What is Weldr?

Weldr is an AI app builder designed for people who eventually want to leave.

Describe what you want to build in plain English. Watch a real Next.js app come to life in your browser as you chat. Then take ownership of exactly the parts you want—piece by piece, whenever you're ready.

Unlike other AI tools that lock you in, Weldr gives you progressive ownership: start fully managed, take control incrementally, and export everything whenever you want.

The Problem We Solve

AI code generation is fast, but there's a catch: the moment you need something custom, you're stuck. Either the AI can't do it, or you export a messy codebase and lose all AI assistance.

Weldr is different:

  • • Take ownership of just one thing while keeping AI assistance for everything else
  • • Your custom code survives regeneration—add business logic that's preserved across updates
  • • Standard output—Next.js, TypeScript, Postgres. Deploy anywhere, hire anyone.

    • How It Works

  • Describe — Tell Weldr what you're building in plain English
  • Preview — See a running app in your browser as you chat
  • Own — Choose what you control vs what stays automated
  • Ship — Export to Git, deploy anywhere

    • Progressive Ownership

    Every part of your app can be in one of three modes:

    | Mode | What It Means | Best For | |------|---------------|----------| | Managed | Weldr handles it completely | Database schemas, auth, CRUD operations | | Extended | Mix generated + custom code | API endpoints, UI components with custom logic | | Ejected | You own it, Weldr validates contracts | Business logic, pricing, algorithms |

    Change the mode anytime. Weldr adapts.

    What You Get

  • • Real code — Next.js 15, TypeScript, PostgreSQL, Tailwind CSS
  • • Live preview — See changes instantly via WebContainers
  • • No lock-in — Export to your repo, deploy to Vercel/AWS/anywhere
  • • Protected code — Your @custom blocks survive regeneration
  • • Contract validation — TypeScript ensures ejected code stays compatible

    • Getting Started Options

    Free Cloud (Recommended)

    Start building immediately. Includes all ownership modes, managed infrastructure, and live preview. → Start building

    Self-Host

    Run Weldr on your own infrastructure. MIT-licensed core. → Installation guide

    Next Steps

  • • Build your first app: Quick Start guide
  • • Understand ownership: Progressive Ownership
  • • See the comparison: Weldr vs alternatives

    • Questions? Email hello@weldr.dev or open a GitHub issue.