The AI app builder you can actually leave

Describe it. Preview it. Own it.

Weldr turns your ideas into full-stack Next.js apps with a live preview you can interact with as you build. Unlike other AI tools, you get progressive ownership—start fully managed, then take control of any part, piece by piece.

  • Live preview as you chat
  • Your custom code, protected
  • Export and deploy anywhere

We’ll spin up a new Weldr chat, extract your domain model in real time, and generate a live preview you can own.

Free to start. MIT-licensed core. No credit card required.

How it works
1You describe

“I need a project tracker with tasks, team members, and a Kanban board”

2Weldr generates

A complete Next.js app with database, API, and UI—running live in your browser

3You own what matters
db: managed       ← Weldr handles
api: extended     ← Mix generated + custom
billing: ejected  ← You fully own

Why Weldr

AI speed without the tradeoffs

Other AI tools make you choose: fast generation OR control. Weldr gives you both.

Instant live preview

See your app running in real-time as you describe it. No waiting for deploys—changes appear instantly in a live browser preview.

Progressive ownership

Start fully managed, then take control piece by piece. Keep database and auth automated while you own the business logic that matters.

No lock-in, ever

Export your code anytime. Deploy anywhere. Your app is real Next.js + Postgres—not a proprietary runtime you can't escape.

How it works

From idea to running app in minutes

Describe what you want, see it come to life, and take ownership of the parts that matter to your business.

  1. 1

    Describe

    Tell Weldr what you're building in plain English. "I need a project tracker with tasks, team members, and a Kanban board."

  2. 2

    Preview

    Watch your app come to life in real-time. A fully functional Next.js app runs right in your browser as you chat.

  3. 3

    Own

    Take control of what matters. Keep the database and auth managed while you own your business logic with @custom blocks that survive every regeneration.

  4. 4

    Ship

    Export to your own repo and deploy anywhere—Vercel, AWS, or your own servers. It's your code, forever.

Your code, protected
// Weldr generates the CRUD
export async function createTask(input: CreateTaskInput) {
  return db.insert(tasks).values(input);
}

// @custom — YOUR code, never overwritten
export async function createTaskWithReminder(input) {
  const task = await createTask(input);
  await notifyAssignee(task);  // Your logic
  return task;
}

Weldr regenerates around your @custom blocks, never through them. Add business logic, integrations, or custom workflows—they're always preserved.

Smart scaffolding

Say it once, get the infrastructure

Mention 'Slack notifications' or 'Kanban board' and Weldr sets up the entire system—not just UI, but the backend, types, and config too.

Pattern recognition that actually works

Just describe what you need naturally. Say "notify the team on Slack when a task is overdue" and Weldr will:

  • Create the notification service with Slack webhook integration
  • Set up the scheduled job to check for overdue tasks
  • Document the SLACK_WEBHOOK_URL you'll need to configure
  • Wire it all together with proper TypeScript types

Built-in patterns

Notifications

Slack, email, SMS

Auth

Auth0, Supabase, Clerk

Kanban

Task boards, pipelines

More capabilities coming soon. Extensible architecture lets teams build custom capabilities for domain-specific patterns.

What you actually get

Real results, not marketing promises.

Time to working app

Minutes

Go from idea to a running, interactive app you can share—not wireframes or mockups.

Your code protected

100%

Your custom code is never overwritten. Weldr regenerates around your changes, not through them.

Lock-in risk

Zero

Export anytime. Standard Next.js, Postgres, and TypeScript—no proprietary runtime.

Who it's for

Built for people who ship

Whether you're a solo founder or a dev team, Weldr gets you to launch faster—without the lock-in.

Technical founders

Ship your MVP in days, not months. Keep full control of the codebase as your product and team grow.

Read the founder guide

Developers

Stop writing CRUD and boilerplate. Focus on the business logic that actually matters while Weldr handles the rest.

See the developer workflow

Agencies

Deliver client projects faster and hand off clean, maintainable codebases they can actually own.

Learn about handoffs

FAQ

Questions teams ask us

Is this another no-code tool?

No. Weldr generates real code—Next.js, TypeScript, Postgres. You get a standard codebase you can open in VS Code, commit to Git, and deploy anywhere.

What happens when I need custom logic?

That's where progressive ownership shines. Mark any part of your app as "extended" to add custom code that Weldr will preserve across regenerations. Or "eject" it entirely to own it yourself.

How is this different from Bolt, Lovable, or v0?

Those tools generate code but lock you into their platforms. Weldr gives you progressive ownership—start managed, take control incrementally, and export everything. No vendor lock-in.

Can I self-host?

Yes. The core is MIT-licensed and runs anywhere. The hosted platform adds collaboration features and higher limits when you need them.

Ready to build something?

Describe your app and see it come to life in minutes. Free to start, no credit card required.