Convex vs Supabase: which one should you pick for your SaaS in 2026?

I used Convex on Pixel-Mart, RendezApp, and PLR Library.

I used Supabase on Bloko.

They aren't direct competitors. They solve different architectures. Picking the wrong one doesn't stop you from building — it costs you time in places you didn't expect.

The fundamental difference

Supabase is a managed PostgreSQL database with an auto-generated API, auth, storage, and realtime subscriptions. You think in SQL. You write migrations. You use Prisma or the ORM of your choice on top.

Convex is a TypeScript-first serverless backend with a built-in database, reactive functions, and a scheduling engine. You think in functions. The TypeScript schema is the database schema. There's no SQL.

What Convex does better

Native reactivity. A Convex query is a subscription. When the data changes, the UI updates automatically — no polling, no manual WebSocket, no cache invalidation.

// This component re-renders as soon as the underlying data changes.
// No other configuration needed.
const orders = useQuery(api.orders.list, { userId });

No boilerplate. There's no separate ORM model. The Convex schema generates the TypeScript types. Doc<"orders"> is the type of your orders. No need to keep a Prisma model in sync with a manual type.

Correct architecture by construction. The query / mutation / action split forces you to never make a network call inside a mutation, never touch the DB inside an httpAction. These aren't conventions — they're compile errors.

query      → read, reactive, never a network call
mutation   → write, transactional, never a network call
action     → external API calls, never direct ctx.db access

Built-in scheduling. ctx.scheduler.runAfter(0, ...) from a mutation — the action runs in the background with no external configuration. No BullMQ, no Redis, no separate worker.

Local development. npx convex dev spins up a full local backend with a dashboard. No Docker, no network configuration.

What Supabase does better

SQL. If your domain is naturally relational — complex joins, materialized views, aggregations over large volumes — PostgreSQL remains unbeatable. Convex has its own indexes and queries, but it doesn't do arbitrary JOINs.

The PostgreSQL ecosystem. Extensions, stored procedures, foreign data wrappers, analytics tools — the entire PostgreSQL ecosystem is available. Supabase is PostgreSQL.

Versioned migrations. Prisma migrations, SQL migrations — schema changes are versioned, reversible, deployable progressively with granular control. Convex handles schema evolution, but with less control over production migrations.

Cost at scale. At high data volumes, Supabase (PostgreSQL) is cheaper to run than Convex, whose billing is based on calls and storage.

Why I chose what, for what

Pixel-Mart → Convex. Marketplace with real-time needs: order status visible instantly to both seller and buyer, push notifications, cart management. Native reactivity was worth the choice.

RendezApp → Convex. Real-time booking: available slots update the moment a reservation is confirmed. Without Convex, that's polling or a WebSocket to maintain.

Bloko → Supabase. Escrow system with critical financial transactions. Seller balance logic, accounting transactions, audit reports — that's SQL territory. PostgreSQL's flexibility and Prisma's versioning were necessary. It's the right choice for this domain.

The decision rule

Does the UI need to mirror the DB in real time with no polling?
→ Convex. Reactivity is native, not a bolted-on layer.

Complex relational queries or high volume?
→ Supabase. Nothing matches PostgreSQL for this.

Maximum DX for a TypeScript MVP?
→ Convex. Zero configuration, schema = types.

Team already familiar with SQL and ORMs?
→ Supabase. The ecosystem is already known to them.

Critical financial transactions with an audit trail?
→ Supabase. SQL control over migrations wins here.

What not to do

Choosing Convex because it's "more modern." Choosing Supabase because it's "better known."

The decision comes from the domain: is my data naturally relational? Does my UI need to be reactive? How critical are my transactions?

These questions have answers. The answer picks the tool.

→ The full Moneroo + Next.js + Convex tutorial — production code → How I work with Claude Code day to day → Launching a SaaS in Francophone Africa — the 7 specifics