Once upon a time in the land of code, there was a big happy monolith. It was simple. Everything was in one place. All the parts of the application lived together like one big family.

But as time passed, things got… complicated. The team grew. The codebase got messy. Changing one small thing required touching five other parts. Deployments were scary. So, developers came up with a grand new plan — break up the monolith!

Enter: Microservices.

What Are Microservices?

Microservices are like tiny apps. Instead of one big codebase, you have many small ones. Each service does one thing. It runs on its own and talks to other services when needed.</

This sounds amazing, right? And it is! But…

The Ugly Side of Going Too Small

Splitting the monolith feels great at first. Teams sprint ahead, building little services like kids building LEGO castles. But soon, problems start to appear.

• Too many services to keep track of
• Harder to understand the full system
• Latency and network issues
• Deployment orchestration becomes a nightmare
• Debugging across services — yikes!

This is called microservice sprawl. You’ve gone from one big problem to many small ones. The complexity didn’t vanish — it just moved around.

It’s like trading a 1,000-piece puzzle for a box of 200 tiny puzzles. Oops.

So, What’s the Alternative?

Meet the modular monolith. It’s kind of like the original monolith, but better organized. Imagine your old monolith with clean rooms, clearly marked doors, and no one is allowed to jump on the bed.

A modular monolith is a single deployable application. But inside, it’s neatly divided into modules. Each module does one thing, has its own boundaries, and uses clear interfaces.

You keep the simplicity of a monolith — and add the structure of microservices.

Why You Might Love a Modular Monolith

• Simpler deployments: One package. One deployment.
• Easier debugging: All logs and behaviors live under one roof.
• Faster dev speed: Less overhead. Fewer network calls.
• Strong boundaries: Modules can’t meddle with each other.

This model is so friendly that many teams are going back to it after microservice burnout. Yes, even the cool kids at tech unicorns.

Okay, But Isn’t a Modular Monolith Just a Fancy Monolith?

Not quite. A classic monolith is a bit of a jungle. Everything depends on everything. A modular monolith is more like a town made of well-planned buildings with roads and signs.

It looks like this:

• Modules: Each one owns its data and logic.
• Clear APIs: Modules interact via interfaces, not through backdoor calls.
• Isolation: You can test or replace a module without breaking others.

You can even extract a module into a microservice later — once you’re sure it needs to scale on its own.

Signs You’re Drowning in Microservice Sprawl

Here are a few red flags that microservices might be causing more harm than good:

• Can’t remember all your services off the top of your head
• Need five services to respond just to show one page
• Doing “orchestration” code that makes no sense
• More time is spent wiring things together than building features

If this sounds familiar, it might be time to reconsider your architecture.

So… How Do You Build a Modular Monolith?

Simple-ish. It takes discipline but not rocket science. Here’s a step-by-step idea to get you going:

1. Split your application into logical domains — like Billing, Users, Inventory.
2. Enforce boundaries. Don’t let one module poke around in another’s data directly.
3. Create shared interfaces for talking between modules.
4. Keep modules independent where possible. Avoid shared logic unless really needed.
5. Use clear ownership. One team per module is ideal.

Think of modules like mini-universes. They live together, but work on their own stuff.

Common Pitfalls to Avoid

• Don’t let modules bleed into each other — that’s back to spaghetti monolith.
• Don’t go half-way. Make sure boundaries are real — not just names on folders.
• Don’t rebuild your app before you test this in one or two parts.

Start small. Learn. Improve over time.

Who Uses Modular Monoliths?

You’d be surprised!

• Basecamp — They’re famous for their modular Ruby monolith.
• GitLab — Ran a monolith for years, very successfully.
• Segment — Merged some services back into a monolith!

Many companies find that a well-structured monolith with modular design gives them the best of both worlds — speed and sanity.

A Word on Communication

One reason people go to microservices is to reduce coordination between teams. But if the modules are clearly owned, and your team works well together, a modular monolith can stay healthy.

Organizational culture matters more than your architecture. Be kind. Communicate. Don’t fight for territory.

When to Go Modular vs Microservices

Here are some handy rules of thumb:

Situation	Go Modular	Go Microservices
Startup or small team	✅	❌
Rapid changes expected	✅	❌
Team per domain/module	✅	✅
Need for independent scaling	❌	✅
Demand for extreme uptime	❌	✅

Look at your current pain points. Let them guide your choice. Don’t follow trends — follow your needs.

Final Thought

You don’t need microservices to be modern. You need clarity, modularity, and good practices.

In fact, a modular monolith might be where your messy microservice journey should have started.

Start small. Organize. Modularize.

Escape the sprawl. Reclaim your sanity.