Microservices vs Monoliths

In this article, we're going to understand the main differences between microservices and monoliths.

Introduction

In the world of software development, there exists a fundamental choice between two architectural approaches: monoliths and microservices. Choosing between them can have a significant impact on your application's development, deployment, and maintenance.

At first glance, the monolith is easy to get started and a good choice for small/medium applications with simple business logic.

Therefore, while monoliths can be a good choice for initially building small and simple applications, their limitations become more apparent as applications grow in complexity and size.

Here's a more nuanced version of the statement you could consider.

Monoliths

Monoliths can be a good choice for small/medium applications with simple business logic due to their ease of development and lower initial cost. However, as the application grows and becomes more complex, scalability limitations and tight coupling can become drawbacks. You should consider microservices for applications with high scalability requirements or complex business logic.

Attributes of Monolith Architecture

Here are a few attributes of Monolith architecture.

1. Single codebase: All functionalities are tightly coupled in a single codebase, making it simple to understand and maintain.
2. Simpler deployment: Deploying the entire application as one unit is straightforward and requires minimal infrastructure setup.
3. Faster development: Initial development can be quicker due to the unified codebase.
4. Limited scalability: Scaling the entire application can be challenging and expensive, especially for specific features.
5. Slower innovation: Updating a single feature requires redeploying the entire application, hindering agility.
6. Tightly coupled dependencies: Changes in one part can impact the entire application, making maintenance complex.
7. Mostly “same skilled” guys: Due to having one single codebase, there is no possibility of using different programming languages in most cases. So, the “guys” for the backend team should have the same technology skills.
8. Fast communication between functionalities: All functionalities live in the same process, and we do not have network or other communication problems and learning curves for making function calls.
9. Always succeeded in operations from the communication perspective: Every operation call, by its nature, is a success call. It doesn’t matter will the function throws an exception or not, in the end, without additional difficulties we’re able to call the function.

Monolith advantages

1. Ease of development: Monoliths are easier to get started with due to their simpler structure and single codebase. This can be beneficial for small teams or projects with tight deadlines.
2. Lower initial cost: Developing and deploying a monolith typically requires less infrastructure and tooling compared to microservices.
3. Simpler debugging and maintenance: Tracing issues and making changes is easier due to the centralized codebase.

Monolith disadvantages

1. Limited scalability: Scaling a monolith can be challenging, especially as individual features grow in complexity or demand.
2. Tight coupling: Changes in one part of the monolith can impact other parts, making updates and releases risky and time-consuming.
3. Reduced agility: Innovation and feature development can be slowed down due to the need to redeploy the entire application for any changes.

Attributes for Microservices

On the other hand, for most cases, we have via-versa attributes for Microservices.

1. Independent services: Per bounded context, we have smaller services that we call microservices. They are independent units of development and deployment.
2. Scalability: Horizontal scaling using loosely coupled communication between microservices allows us to scale without any issues.
3. Faster innovation: Updating a single feature on a given microservice requires redeploying only the microservice itself, not the whole service.
4. Loosely coupled dependencies: Using asynchronous communication, it is possible to decouple microservices completely, and in the future, it will make our system robust, easily maintainable, extensible, and reusable.
5. Increased complexity: Nothing is free. So, applying microservice architecture requires a learning curve for additional technologies.
6. Network communication overhead: Every service has its network, and it adds additional complexity from the communication perspective.
7. Debugging challenges: Not being in a single process makes application debugging challenging.
8. Multilanguage usage: We have a language-agnostic nature in Microservices. It allows you to use different programming languages and technologies per microservice.
9. Team with different skilled guys: The Ability to apply different programming languages and technologies in development helps extend the search border regarding developers.

Choosing the right path.

The optimal architecture depends on your specific needs and priorities. Here are some factors to consider.

1. Application complexity: Monoliths are suitable for simpler applications, while microservices shine for complex, evolving systems.
2. Scalability requirements: If individual features need to scale independently, microservices offer a clear advantage.
3. Development team structure: Microservices benefit from smaller, cross-functional teams focused on specific services.
4. Deployment and maintenance overhead: Monoliths are easier to manage initially, but microservices can be more efficient in the long run.