Picking a Database for Vibe Coding: Supabase vs Neon vs Turso vs Convex, Explained in One Table

The short version: a decision table

In a hurry? Use this table and decide in 10 minutes:

Need user accounts + file storage + shipping today → Supabase. The full Postgres bundle — Auth, Storage, Realtime in one place. The default answer for "usable product in a weekend."

Already on Postgres, want serverless elasticity + branchable databases → Neon. Usage-based pricing, scale to zero, and an isolated database per PR for previews — the best team-collaboration experience.

Lightweight app, read-heavy, want to deploy close to users → Turso. SQLite replicated at the edge, absurdly light, generous free tier. Great for content sites and small tools.

Need realtime sync / multiplayer state, all-in on TypeScript → Convex. The database is the backend; schemas are code. The smoothest option for AI-generated code, with realtime as the default.

Don't pick Firebase (for new projects). Unless you're already in its ecosystem. The mental overhead of NoSQL data modeling is heavier than you think — not worth it in the vibe phase.

Vibe projects need different things from databases

Traditional selection criteria: QPS, transactional consistency, ops cost. Vibe projects rank completely differently. Number one is time-to-first-query: can you go from "I have an idea" to "database running" in 10 minutes? Number two is serverless-friendliness: does it scale to zero so you're not paying for idle? A vibe project sits unused 90% of the time — paying for idle is the dumbest line item. Number three is integration density: do Auth, file storage, and realtime subscriptions come built in, or do you glue three more services together? Every extra service doubles the glue code your agent writes and doubles the pitfalls.

There's also a hidden metric: how well your AI writes for it. Having an agent write a Prisma schema plus migrations versus writing a Convex TypeScript schema — the success rates aren't even close. Factoring "can my agent get it right first try" into your choice isn't embarrassing — it's just the reality of the vibe era.

The four mainstream options, broken down

Supabase: the full bundle, the safe default. Managed Postgres plus Auth, Storage, Edge Functions, and Realtime. Its biggest strength is "no decisions required": how to model users, where avatars live, how realtime notifications work — all answered officially. The free tier comfortably carries you to thousands of users. Downsides: Postgres migrations are still migrations, and agent-generated SQL still blows up when schemas churn; Realtime needs tuning at high concurrency. But for a first vibe project, it's the highest fault-tolerance choice.

Neon: the serverless answer for Postgres purists. If you're committed to Postgres (ecosystem, tooling, hiring), Neon is the best serverless form. Its killer feature is database branching: every PR automatically forks an isolated database, data issues get verified against the preview, branches auto-delete on merge. That feature alone is worth the price. Downside: it's database-only — Auth and storage are still on you (usually Clerk + R2/S3).

Turso: SQLite so light it feels unreal. SQLite replicated to edge locations worldwide, ultra-low read latency, writes go back to primary. Perfect for blogs, docs sites, small tools, personal projects — read-heavy workloads. libSQL is a SQLite fork with near-identical dialect, zero mental overhead. Downsides: stay away for complex queries and write-heavy workloads; the ecosystem is an order of magnitude smaller than Postgres, so fewer Stack Overflow answers when weird things happen.

Convex: the backend rewritten for the AI era. No split between "database" and "backend" — schemas, queries, and mutations are all TypeScript, realtime sync is the default. Agent success rates writing Convex code are the highest of these options, because there are no SQL string concatenations, no migration files, no ORM impedance mismatch. Downsides: the deepest vendor lock-in of the bunch, migration-out costs the most; per-function-call billing can produce invoice surprises if you're careless.

Three counter-intuitive tips

One: don't pick the "strongest" — pick the one you won't regret deleting. At MVP stage, the cost of choosing wrong is far lower than the cost of spending two weeks choosing right. Before your data volume ever needs sharding, your project will have been rewritten three times — the "scalability" you're agonizing over has a 99% chance of never mattering. Pick the one that lets you start writing tonight.

Two: get it working on local SQLite first, then decide about the cloud. Criminally underrated: Prisma + SQLite for local dev means zero config, zero cost, and your agent gets it right first try. When the app genuinely needs multiple users and deployment, migrate to Turso (a one-line config change, dialect-compatible) or Supabase. Introducing a cloud database before the idea is validated is prepaying complexity you haven't earned.

Three: pick Auth and database from the same vendor. The biggest hidden time sink in vibe projects: Supabase Auth + Supabase is 5 minutes, Clerk + Neon is an hour (acceptable), Auth0 + self-hosted Postgres is half a day minimum. User accounts are a rite of passage for every project — halving the integration cost of "login" plus "data storage" beats any performance optimization.

When to replace your first database

Three signals — consider migrating when any one appears: the free tier is exhausted and revenue doesn't cover it yet (optimize queries first, don't rush to switch); queries are getting complex enough that the ORM can't express them (business complexity has arrived, worth one serious selection round); the team grows past 3 people (branch databases and preview environments start paying off).

Remember: in the vibe coding era, a database isn't an "architecture decision" — it's a consumable. Get the project alive first; make it elegant later.