Engineering Apr 09, 2026

Designing Software Architecture for Scale

Designing Software Architecture for Scale

Author

Nam Pham

The MVP Trap (I’ve been there)

When building an MVP, speed is everything. You just want to ship. So naturally, you:

  • Put business logic directly in controllers
  • Use a single database for everything
  • Skip boundaries because “we’ll refactor later”

The problem is… “later” comes faster than expected.

One day your product suddenly has:

  • 10x more users
  • Multiple teams working on the same codebase
  • Real enterprise clients asking for SLAs, security, audit logs…

And then your architecture starts fighting you.

Decision #1: Separate Domain Logic Early (Even a Little)

I used to think Clean Architecture was overkill for MVPs. Now I think full Clean Architecture might be overkill — but ignoring separation entirely is worse.

A simple rule I follow now:

Keep business logic out of delivery layers (API, UI)

Even just having:

  • services/ or use-cases/
  • instead of putting everything inside controllers

This makes it much easier to:

  • reuse logic later
  • test things without spinning up the whole app
  • migrate to microservices (if needed)

Decision #2: Design for Read Scalability First

Most apps scale reads before writes.

Instead of over-engineering:

  • Start with a monolith
  • But make it read-friendly

Some practical things I’ve been trying recently:

  • Introduce caching early (Redis, even simple in-memory)
  • Separate read models (basic CQRS-lite, nothing fancy)
  • Use pagination everywhere (seriously, everywhere)

You don’t need full CQRS — just don’t assume one DB query will always be cheap.

Decision #3: Be Careful With “Shared Database Everything”

This one hurts.

At MVP stage, one database is fine. But:

Sharing the same schema across multiple features without boundaries becomes a nightmare.

What helped me:

  • Group tables by domain (even in same DB)
  • Avoid cross-domain joins unless really necessary
  • Use APIs internally instead of direct DB access (even if same codebase)

It’s like pretending you have microservices… without actually suffering from them yet.

Decision #4: Async First (Where It Makes Sense)

A mistake I made:

Everything was synchronous because it was easier.

Later:

  • slow APIs
  • timeouts
  • bad UX

Now I try to identify early:

  • emails → async
  • reports → async
  • heavy processing → async

Tools I’ve experimented with recently:

  • message queues (Kafka, RabbitMQ)
  • lightweight job queues (BullMQ, Sidekiq-like systems)

You don’t need to go “full event-driven”, but having async boundaries helps a lot.

Decision #5: Observability Is Not Optional Anymore

This is something I ignored until production issues happened.

Now even in MVP, I try to include:

  • structured logging
  • basic tracing (OpenTelemetry is getting easier to adopt)
  • metrics (even simple ones)

Because when scaling happens:

You can’t fix what you can’t see.

Some Newer Things I’m Exploring

Lately I’ve been experimenting with:

  • Serverless + edge functions (for scaling reads globally)
  • Backend-for-Frontend (BFF) pattern for complex UI
  • Using GraphQL selectively (not everywhere like before 😅)
  • AI-assisted monitoring (still early, but interesting)

Not all of these are necessary — but they’re changing how I think about scalability.

Final Thought

You don’t need perfect architecture at MVP stage.

But you do need:

  • clear boundaries
  • awareness of future scaling points
  • and discipline to avoid “temporary hacks” becoming permanent

Because the real cost isn’t building fast —
it’s rebuilding everything later.