Popular Software Architecture Types Explained

What Is Software Architecture? Choosing the right software architecture is one of the most important decisions in any development project. It affects scalability, maintainability, performance, team structure, and even deployment strategy.

Software architecture is the high level structure of a software system. It defines:

• Components

• Responsibilities

• Communication patterns

• Technology decisions

• Deployment structure

Think of it as the blueprint of your application.

Whether you're building a small Node.js CRM, a SaaS platform, or a large scale distributed system like Netflix or Amazon, architecture defines how your system behaves under growth and complexity.

In this guide, we’ll cover:

• Major types of software architecture

• When to use each one

• How to set them up

• Practical examples

• Benefits and common mistakes

Let’s dive in.

Major Types of Software Architecture

1. Monolithic Architecture

What It Is?

A monolithic application is built as a single unit. All modules - UI, business logic, and database - are tightly connected and deployed together.

Frameworks like Django and Laravel often start as monolithic systems.

When to Use

• Small to medium applications

• MVP development

• Small development teams

• Limited scalability requirements

2. Layered (N-Tier) Architecture

What It Is?

This divides the application into logical layers:

• Presentation Layer (UI)

• Business Logic Layer

• Data Access Layer

• Database Layer

This is extremely common in enterprise apps and CRM systems.

When to Use:

• Business applications

• Systems with clear separation of concerns

• Teams that want structured codebases

3. MVC (Model-View-Controller)

What It Is?

Separates application into:

• Model - Data & business rules

• View - UI

• Controller - Handles input & logic

Common in frameworks like Express.js and Ruby on Rails.

When to Use:

• Web applications

• CRUD-heavy systems

• Structured frontend-backend separation

4. Microservices Architecture

What It Is?

Application is divided into small independent services, each responsible for a specific function.

For example:

• Auth Service

• Payment Service

• Notification Service

Large platforms like Netflix use microservices to scale efficiently.

When to Use:

• Large-scale systems

• High traffic applications

• Teams working independently

5. Event-Driven Architecture

What It Is?

Services communicate via events instead of direct calls.

Example:
Order placed -> Event published -> Payment + Email services react.

Often implemented using tools like Apache Kafka.

When to Use:

• Real-time systems

• Async processing

• High scalability needs

6. Serverless Architecture

What It Is?

Backend logic runs in cloud managed functions.

Example platform: AWS Lambda

You deploy functions instead of managing servers.

When to Use:

• Startups

• Event triggered apps

• Cost sensitive workloads

7. Clean Architecture

What It Is?

Focuses on keeping business logic independent from frameworks and databases.

Popularized by Robert C. Martin.

Core rule:

"Dependencies always point inward."

When to Use:

• Long term maintainable systems

• Domain heavy applications

• SaaS platforms

8. Hexagonal Architecture (Ports and Adapters)

What It Is?

Business logic is isolated in the center. External systems (DB, API, UI) connect through adapters.

When to Use:

• Complex enterprise systems

• Applications needing multiple integrations

How to Install and Set Up Different Architectures

Architecture is not something you "install." You implement it through project structure and design decisions.

Below are practical setup approaches.

Setting Up MVC with Express.js

Step 1: Install Dependencies

npm init -y
npm install express

Step 2: Create Folder Structure

/controllers
/models
/routes
/views
app.js

Step 3: Separate Concerns

• Controllers -> Business logic

• Models -> Database schema

• Routes -> HTTP endpoints

This structure enforces MVC separation.

Setting Up Layered Architecture

Structure example:

/presentation
/business
/data
/infrastructure

Each layer should depend only on lower layers.

Example:

• Presentation calls Business

• Business calls Data

• Data talks to database

Setting Up Microservices

Step 1: Split Services

Create separate repositories or folders:

/auth-service
/payment-service
/notification-service

Step 2: Independent Deployment

Use Docker containers for each service.

Step 3: Communication

• REST APIs

• Message brokers

• Event streams

Setting Up Serverless

Using AWS Lambda:

1. Install AWS CLI

2. Create a function

3. Deploy code

4. Connect via API Gateway

You focus on function logic, cloud handles scaling.

Practical Examples

Example 1: CRM Application

Small CRM:

• Layered architecture

• MVC pattern

• Single deployment

Large SaaS CRM:

• Microservices for:

  • Authentication

  • Billing

  • Notifications

• Event driven email triggers

Example 2: E-commerce System

Monolith (early stage):

• Single backend

• Single database

Scaled version:

• Product service

• Order service

• Payment service

• Event driven order processing

Example 3: Real-Time Chat App

Best fit:

• Event driven architecture

• WebSockets

• Microservices

• Message broker

Benefits of Choosing the Right Architecture

1. Scalability

Microservices allow independent scaling.

2. Maintainability

Clean architecture reduces technical debt.

3. Faster Development

Layered and MVC structures simplify teamwork.

4. Better Testing

Separated concerns = easier unit testing.

5. Improved Reliability

Event driven systems isolate failures.

Common Mistakes Developers Make

1. Overengineering Early

Using microservices for a 2-person startup is unnecessary.

Start simple. Scale later.

2. Ignoring Separation of Concerns

Mixing database queries inside controllers leads to messy code.

3. Tight Coupling

Hard dependencies make refactoring painful.

4. No Documentation

Architecture decisions must be documented.

5. Premature Optimization

Don’t design for millions of users if you have 100.

How to Choose the Right Architecture

Ask these questions:

1. How many users?

2. Expected growth?

3. Team size?

4. Deployment infrastructure?

5. Domain complexity?

Quick Decision Guide

Conclusion

Software architecture is not about trends, it’s about solving the right problem at the right scale.

Start simple:

• Monolith for MVP

• Layered for structure

• Microservices for scale

• Clean architecture for longevity

• Event driven for real time systems

Choose based on business needs, not hype.

A well designed architecture saves years of technical debt and makes scaling predictable instead of painful.