Monolithic vs Microservice Architecture – A Developer’s Perspective

Monolithic( Monolithic Architecture )

Monolithic and monolithic architecture are the same — so don’t get confused by the terminology.

In a monolithic architecture, the entire application is developed as a single codebase. All components such as the database layer, routes, controllers, services, etc., are built and managed together.

For example, suppose you're developing an e-commerce application. In a monolithic setup, features like user authentication (signup/login), cart, payments, and orders — all reside in the same codebase and are tightly coupled.

🔑 Key Characteristics:

• The application follows the same programming language/technology stack.

• Everything is managed within a single codebase.

• The entire application is deployed together as one unit.

If you follow a monolithic architecture, you might have:

• One large server-side application that handles everything — users, products, orders, payments, etc.

✅ Pros:

• Easy to develop and deploy (especially for small teams or projects).

• Easier to test and debug since all components are in one place.

• Teams work with a single tech stack, making collaboration and debugging easier.

❌ Cons:

• Difficult to scale specific parts independently.

• A change in one part of the application may require changes elsewhere.

• Even for a small change (e.g., updating the cart feature), you must rebuild and redeploy the entire application.

• A failure in one module can potentially crash the entire system.

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Microservices (Microservice Architecture)

Microservices is an architectural style of developing an application as a set of small, independent, and loosely coupled services, where each service is focused on serving a specific business functionality or customer need.

Each service/component:

• Has its own database

• Is independently deployable

• Communicates with other services via APIs (Application Programming Interfaces)

🛒 Example:

In an e-commerce platform, instead of one big application, you develop each feature as a separate service:

• User Service

• Product Service

• Order Service

• Payment Service

• etc.

🔑 Key Characteristics:

• Loosely coupled services

• Independent deployment

• Can use different technologies (programming languages, frameworks)

• Separate databases for each service

Each of these:

• Can have its own database

• Can be built using different languages or frameworks

• Can be deployed, updated, or scaled independently

✅ Pros:

• Faster development and deployment

• High scalability (scale only the service that needs it)

• Flexible technology choices (teams can choose different tech for each service)

• Fault tolerance (if one service fails, others can still function)

❌ Cons:

• Increased architectural complexity

• Harder to debug and test due to distributed nature

• Higher infrastructure cost (especially with containers, orchestration, etc.)

📦 Real-World Analogy

Think of a restaurant:

• Chef = Food Service

• Waiter = Order Service

• Cashier = Payment Service

• Cleaner = Maintenance Service

Each works independently, but together they serve the customer.