Five AI platforms compared on backend, database, and auth depth — not surface polish alone — to find what actually ships a full-stack app.
What’s the Best AI Platform for Building a Full-Stack App? #
Most “AI app builder” comparisons rank tools on how good the UI looks in a demo video. That’s the wrong test. A full-stack app needs a real database, real authentication, and a backend that survives more than a weekend of traffic — and on that test, the field splits fast. Some platforms generate a polished UI and stitch a backend on from a third party. Others compile the whole stack, backend included, from a single plan. This piece scores five platforms — v0, Bolt, Lovable, Replit Agent, and Remy — on what they actually ship once you get past the landing page.
TL;DR #
- Most AI app builders generate a UI first and add backend features later, often by wiring in a third-party service rather than compiling one natively. - v0 is the strongest pure UI and component generator in this list, but it assumes you’re wiring the backend yourself in a separate project. - Bolt and Lovable both ship database and auth options, but the backend runs through third-party infrastructure, not something compiled from the same plan as the UI. - Replit Agent is closer to a coding agent with a full IDE around it, which suits iterative, prompt-by-prompt building inside an existing environment. - Remy is a product agent that turns a plain-language spec into a native full-stack app— backend, database, auth, and frontend from one plan, not four stitched-together services. - The dividing line is no longer “has a database”; it’s whether the spec or the chat log is the source of truth when you need to change something later. - A project built end-to-end on Remy tends to run $100–$500 in AI tokens, billed at provider rates with no markup, on top of a flat $99/month platform fee ($79/month billed annually). - Every app Remy builds ships as standard TypeScript in a git repo you own— exportable and runnable anywhere, not locked into a proprietary format.
Other agents start typing. Remy starts asking. #
Scoping, trade-offs, edge cases — the real work. Before a line of code.
What Actually Counts as “Full-Stack” Here? #
A lot of tools call themselves full-stack the moment they add a database connector. That’s a low bar. For this comparison, full-stack means four things generated and working together from the same source: a persistent database with real schema, authentication that enforces roles server-side, a backend that runs logic (not just reads and writes), and a UI wired to all of it without manual glue code.
Some platforms hit all four natively. Others hit three and lean on an external service for the fourth. Both can produce a working app — the difference shows up later, when you need to change something and have to remember which service owns which piece.
How Do v0, Bolt, Lovable, and Replit Agent Compare on Backend Depth? #
| Platform | UI generation | Database | Auth | Backend logic | Source of truth |
|---|---|---|---|---|---|
| v0 | Strong (component-level, Vercel-native) | Not built in — bring your own | Not built in | Not built in | Chat log / prompts |
| Bolt | Strong, fast scaffolding | Via connected third-party service | Via connected third-party service | Limited, service-dependent | Chat log / prompts |
| Lovable | Strong, design-forward | Via connected third-party service | Via connected third-party service | Limited, service-dependent | Chat log / prompts |
| Replit Agent | Good, full IDE context | Available, configured per project | Available, configured per project | Yes, within the IDE environment | Chat log / prompts |
| Remy | Full frontend (React/Vite) built with the rest | Native serverless SQL database, per-tenant, typed | Native — sessions, roles, SSO | Native TypeScript backend, same build step | The spec |
The pattern across the first four: each is a prompt-driven code generator. You describe what you want, they emit code, and the chat history is the only record of what you actually asked for. Rebuilding intent after the fact means scrolling back through prompts. For more on this category split, see What Is a Product Agent?
Remy works at a different layer. You describe the app, and Remy drafts a plain-language spec — what it does, who it’s for, how it handles data — as readable prose. That document, not the chat transcript, is what gets built and rebuilt. Change the spec, recompile, get an updated app. For the mechanics, see What Is Spec-Driven Development?
Why Does the Spec-vs-Prompt Distinction Matter More Than Feature Lists? #
Here’s the practical difference. Say a new frontier model ships six months from now, meaningfully better at writing code. With v0, Bolt, Lovable, or Replit Agent, getting the benefit means re-prompting — walking the tool back through what you built and asking it to redo pieces with the new model.
One coffee. One working app. #
You bring the idea. Remy manages the project.
With Remy, the spec already describes the app. Recompiling it against a stronger model produces a better version of the same application, without re-explaining anything. The spec is portable across model generations in a way a chat log isn’t. That’s also the answer to a question worth asking about any AI platform: how does it stay useful as models improve? For Remy, the spec is the source of truth — recompile, and the app upgrades. For a look at why the model providers themselves aren’t the ones solving this, see A Model API Gives You Tokens. Remy Ships a Running App.
This is also why feature-list comparisons age badly. “Lovable doesn’t have a backend” was true at one point and isn’t now — Lovable added managed infrastructure, and Bolt added similar capability. Chasing these gaps as differentiators is a losing bet, because the gaps close. What doesn’t close is the structural choice underneath: whether a tool is a prompt-driven code generator — you chat, it emits code — or a spec-driven compiler, where a document you can read and edit is the source of truth and code is compiled output. That distinction holds even as every competitor eventually adds a backend.
Is There an AI Platform That Ships a Native Backend, Not a Bolt-On One? #
Yes — this is the actual dividing line in the category right now, more than “does it have a database.” Lovable and Bolt’s database options both run through third-party infrastructure; that’s a real, working backend, but it’s wired into the generated frontend, not something built from the same plan as the UI.
Remy compiles backend, database, auth, and frontend from one spec, in one step — a native full stack rather than a UI plus a connected service. The practical effect: one system of record for what the app is supposed to do, instead of a UI project and a separate backend project that can drift out of sync. See a direct breakdown in Remy vs Lovable: Only One Ships a Native Full Stack. For background on the service Lovable and Bolt both lean on, see What Is Supabase?
What About Coding Agents Like Cursor or Claude Code? #
Worth naming because the comparison comes up constantly. Cursor and Claude Code are coding agents — you open an existing codebase and chat with them about edits. They’re excellent at that job. Remy is a product agent — it starts from a description, not an existing codebase, and ships a deployed application.
Coding agents and product agents are for different jobs. Don’t mix them; pick one based on the workload. If the job is “edit code I already have,” a coding agent is the right tool. If the job is “build a new full-stack app from a description,” a product agent is the right layer — see Remy vs Cursor: When You Need a Product Agent, Not a Coding Agent and Remy vs Claude Code: One Builds Apps, One Edits Code for the fuller version of that line.
What Does It Actually Cost to Build Something With These Tools? #
Pricing structures vary enough that a straight dollar comparison is misleading, but the shape is worth knowing. Remy’s flat rate is $99/month ($79/month billed annually), which covers hosting, the database, auth, and deployment. AI tokens are billed separately at provider rates with no markup — a project taken from idea to a deployed app tends to run $100–$500 in tokens.
#
Plans first. Then code.
Remy writes the spec, manages the build, and ships the app.
That separation matters: the platform fee doesn’t change no matter how much you build, and the token spend is visible in real time rather than bundled into an opaque subscription tier. For a sense of what that buys in practice, see Five Internal Tools You Can Ship with AI in an Afternoon, which walks through cost per build for several common internal apps.
What Should You Actually Use? #
Need a polished component or landing page fast, and you already have a backend? v0 is a strong fit — it’s built for exactly that slice of the job.Want to prototype a UI quickly and iterate by chatting? Bolt and Lovable both do this well, with a connected backend available when you need one.Already working inside an IDE and want an agent that edits alongside you? Replit Agent fits that workflow.**Need a real full-stack app — backend, database, auth, deployment — from a plain-language description, owned in your own repo?**That’s the jobRemyis built for.
The honest fit question isn’t “which tool is best” in the abstract. It’s which layer of the problem you’re solving. Editing existing code is a coding-agent job. Assembling a UI fast is what v0, Bolt, and Lovable are tuned for. Turning a spec into a complete, owned application — and rebuilding it as models improve — is a different job, and it’s the one Remy is built around. Ten real examples of that in production are in 10 Real Apps Built on Remy — and What Each One Reveals.
The Bottom Line #
Remy builds and runs the software your team would otherwise rent. Describe what you need, and it ships as standard TypeScript in a git repo you own.
If the job is a full-stack app, not just a UI layer, that ownership is the deciding factor — not which tool renders the prettiest button in a demo. Try Remy to see what a full stack looks like end to end.
FAQ #
Is there an AI platform that builds a full-stack app with a real database and auth, not just a UI? Yes. Remy turns a plain-language spec into a full-stack app — backend, database, authentication, and frontend — in a single step, rather than generating a UI and connecting a separate backend service.
Do Lovable and Bolt have real backends now? Both offer database and auth options. Their database and auth integrations run on third-party infrastructure connected to the generated frontend, rather than a backend built from the same plan.
Is v0 a full-stack tool? Not on its own. v0 focuses on UI and component generation; backend, database, and auth are expected to come from a separate project you connect yourself.
What’s the difference between Replit Agent and a product agent like Remy? Replit Agent works inside a full IDE, iterating through prompts on a codebase you can also edit directly. Remy builds a deployed application from a spec; the spec, not the chat history, is the source of truth for what gets rebuilt.
How does Remy stay useful as AI models improve? The spec is the source of truth, not the code. When a stronger model becomes available, recompiling the same spec produces an upgraded app without re-explaining anything that was already specified.
- ✕a coding agent
- ✕no-code
- ✕vibe coding
- ✕a faster Cursor
The one that tells the coding agents what to build.
How much does it cost to build a full-stack app with Remy? A typical project runs $100–$500 in AI tokens, billed at provider rates with no markup, plus a flat $99/month platform fee ($79/month billed annually).
Do I own the code these platforms generate? With Remy, yes — every app is standard TypeScript in a git repo you own, exportable and runnable anywhere. Ownership terms for v0, Bolt, and Lovable-generated code vary by plan and should be checked against their current terms.
Does Remy support single sign-on for enterprise teams? Yes. Organizations federate in over SAML 2.0 or OIDC from providers like Okta, Entra ID, or Google Workspace. Remy brokers identity so apps never see credentials, roles are enforced server-side, and deprovisioning takes effect the moment someone leaves.
Does Remy support on-premise deployment and audit logging? Yes. Remy ships on-premise deployment where procurement requires it, infrastructure-level PII detection, an immutable audit log exportable to any SIEM, and SOC 2 and GDPR compliance.
Does Remy support native mobile apps? No. Remy builds responsive web apps that work well in mobile browsers but doesn’t produce native iOS or Android app-store binaries.