App rescue
Lovable vs Bolt vs Replit vs Base44: which AI builder, and how hard is it to leave?
How Lovable, Bolt, Replit and Base44 handle your backend, code and data, and what to check before you launch an MVP on one of them.
4 min read
Key takeaways
- All four builders get an idea on screen fast; they differ most in where your backend and data live.
- Lovable and Bolt build web apps on a managed backend (Lovable Cloud or Bolt Database by default, Supabase as an option).
- Replit is a full development environment with its own hosted Postgres; Base44 keeps your app on Base44's own backend.
- Before launch, check how you would get your code, your data and your secrets out, not just how fast you can build.
On this page
Lovable, Bolt, Replit and Base44 all promise the same thing: describe an app, get a working one. For a first version that promise mostly holds. The differences show up later, when you need real users, real data and a plan for growing past the builder. This guide compares them on the questions that matter at that point.
Builders change quickly, so every detail below links to the tool’s own documentation. Check those pages for the current state before you decide.
The short version
| Lovable | Bolt | Replit | Base44 | |
|---|---|---|---|---|
| What it is | AI app builder for web apps | AI app builder for web apps | Full development environment with an AI agent | AI app builder with its own backend |
| Default backend | Lovable Cloud, or your own Supabase | Bolt Database, or Supabase | Replit’s hosted Postgres | Base44’s backend |
| Getting the code out | GitHub sync or download | GitHub or download | GitHub or download | Export, or the base44 eject command |
| The main thing to plan | Moving data and secrets off Lovable Cloud | Choosing the database before you have data | Moving the database and Replit-specific setup | Replacing the backend if you leave |
Lovable
Lovable builds React web apps. The backend is either Lovable’s built-in Cloud, a Supabase project you connect, or third-party APIs (Lovable FAQ). Lovable states that your apps and code are yours, and on paid plans you can download the whole codebase.
Two details matter when you go to production:
- Project data exports, but not everything with it. Lovable’s data export does not include stored files, Edge Function code or secrets (Lovable FAQ). Plan to move those separately.
- GitHub creates a new repository. You cannot connect an existing repository or start a project from one (Lovable FAQ).
If your app runs on Supabase, the access rules (row-level security) are the first thing to review. The Lovable to production checklist covers the rest.
Bolt
Bolt also builds web apps in the browser and can host them. New projects use a Bolt database by default, and Pro and Teams plans can choose Supabase instead (Bolt docs).
The decision to make early: which database. Bolt’s documentation warns that switching from a Bolt database to Supabase later takes extra steps, that connecting Supabase to a project that already has a Bolt database replaces the connection and may cause data loss, and that there is no supported path from Supabase back to a Bolt database (Bolt docs). If you expect to need Supabase’s features or more control over your data, choose it before real data arrives.
Replit
Replit is closer to a full development environment than a pure app builder: an editor, an AI agent, hosting and a database in one place. That makes it flexible, and it means more of your setup is Replit-specific.
For the database, Replit’s development database cannot be reached by other apps or external database tools, while the production database can be reached from any PostgreSQL client using the connection string in its Settings tab (Replit docs). Moving off Replit therefore means exporting the production data deliberately and recreating your secrets as environment variables wherever the app runs next.
Base44
Base44 builds the app and runs its backend for you. You can download the code with the base44 eject command, but the ejected code is linked to a new Base44 project and still uses Base44’s backend (Base44 docs). In practice, leaving Base44 means rebuilding the backend (database, authentication and server logic) somewhere you control, then moving the data across.
That isn’t a reason to avoid Base44. It is a reason to know the plan before your app holds customer data and payments.
Which one for your MVP?
- You want a React app on Supabase with GitHub sync: Lovable.
- You want hosting and a database in one place, with Supabase as an option: Bolt, deciding the database up front.
- You or a developer will keep working in the code directly: Replit, since it’s a real development environment.
- You want the backend fully handled and expect to stay: Base44.
Whichever you pick, the same production basics apply: access rules enforced on the server, secrets out of the browser, a real database with backups, payments tested end to end, and hosting in your name. The vibe coding security checklist lists the issues that show up again and again.
Before you launch on any of them
Ask three questions:
- Code: can I get the full source into a repository I own?
- Data: how do I export the database, files included, and restore it somewhere else?
- Secrets: where do my API keys live, and how do I move them?
If any answer is “I don’t know”, find out before real users arrive. Taking an AI-built app to production, on any of these builders, is what an app rescue does.
