Node.js MVP Architecture: Build Fast Without Making a Mess

Node.js is flexible — which is both its strength and its weakness. Without structure, Node.js projects become spaghetti fast. Here's a practical architecture that balances speed with maintainability.

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Recommended Project Structure

src/
  routes/           # Express/Fastify route handlers
    auth.ts
    users.ts
    products.ts
    webhooks.ts
  services/         # Business logic (called by routes)
    auth.service.ts
    user.service.ts
    product.service.ts
    stripe.service.ts
  db/               # Database access (Prisma/Drizzle)
    prisma.ts       # Prisma client instance
    queries/        # Reusable query functions
  middleware/        # Auth, validation, error handling
    auth.ts
    validate.ts
    error-handler.ts
  lib/              # Shared utilities
    email.ts
    logger.ts
  types/            # TypeScript types and interfaces
  app.ts            # Express/Fastify app configuration
  server.ts         # Server startup

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Architecture Principles for MVPs

1. Three-Layer Architecture

Routes → Services → Database

• Routes handle HTTP (parse request, send response)
• Services contain business logic (validation, calculations, orchestration)
• Database handles data access (queries, mutations)

2. Input Validation at the Edge

Use Zod to validate all incoming data at the route level before it reaches business logic.

3. Centralized Error Handling

One error handler middleware that catches all errors, logs them, and sends appropriate HTTP responses. Individual routes throw errors; the middleware handles them.

4. TypeScript Everywhere

No any types. Define interfaces for all API request/response shapes, database models, and service function parameters.

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Framework Choice

For MVP: Express if you want the largest ecosystem. Fastify if you want better TypeScript support and performance. Hono if you're deploying to edge/serverless.

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Database Patterns

• Use Prisma for type-safe database access
• Create reusable query functions in db/queries/
• Use transactions for operations that modify multiple tables
• Add indexes on columns used in WHERE and JOIN clauses
• Use migrations (prisma migrate dev), never db push in production

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Don'ts for MVP Architecture

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Need a Node.js boilerplate? Browse on MVPHub.

Connecting to Next.js? Read How to Connect Next.js + Node.js API.

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