Monolithic vs Microservices: Which Architecture Is Right?

Monolithic vs. Microservices Architecture: Which Approach Is Right for Modern Applications?

A few aspects. A tiny crew. An increasing number of customers. In the beginning, all runs well.

Then things get complicated with the growth of business.

More features appear. More developers are hired. Part of the app needs to be modified, and another part is unexpectedly required to process double traffic. The seemingly simple modifications start involving serious steps of planning because the change in one aspect may influence others.

The software hasn’t gotten any worse. It just exceeded its original design.

The Monolith: When Everyone Works under One Roof

Imagine your business when it was starting up. There could have been only a few employees at that time, with each of them handling various aspects of the business. Someone would handle the customer support, operations, and accounting for you. Since there are very few people involved, it becomes easier for everyone to work together.

A monolithic architecture is based on the same principle where user accounts, billing, orders, and reporting systems are developed as one module. When your application is small, a monolithic architecture can be very useful. It is easier to develop, test, deploy and understand.

However, with time, there will be changes in your business. You will add new employees who will get additional responsibilities. There will be inter-departmental dependencies where decisions made in one department will affect the other departments.

Microservices: Giving Each Team Its Own Responsibility

At a certain point, as the company continues to grow, it may not be possible to have all people do everything in the process. The customer’s team will take care of customers; the payments’ team will take care of payments, and the orders’ team will take care of orders.

However, the problem is that even though the teams are separate, they are all working towards the same end result – which is the achievement of the business objective. This is how microservices approach matters.

Microservices architecture split the application into separate services, where each service takes care of an individual function.

It will become possible to update the payments service without necessarily updating the orders’ service. In case the number of orders grows, it will become possible to scale only the order service. It will also be possible to have several teams work on their services separately.

For an expanding application, this will become very important. However, the trade-off is that as more independence becomes possible, more coordination is needed as well.

Monolithic vs. Microservices: What Really Changes?

What gets changed in going from the monolithic application to the microservice application? Let us consider what gets changed in the growing business when different teams become responsible for different tasks.

• Scaling: When using a monolith architecture, you might need to scale your entire application even though only one part requires increased resources. In case of microservices, only the affected service is scaled independently from other services.
• Deployment: Monolithic architecture requires you to update the entire application, while microservices can give an opportunity to change only the required service.
• Failure: When using a monolith, one error can affect another part of the application. While microservices can isolate the effect, finding out where the error comes from can be harder.
• Development: When working with a monolith, a small team will have fewer problems. However, as teams get larger, microservices allow you to operate independently.
• Complexity: However, there is always a downside of monolith more services lead to more connections, surveillance, and management. Microservices help to solve some challenges but never remove complexity only relocate it.

So, Which One Should You Choose?

Returning to our developing company, there is no requirement stating that all the companies must be developed as a bunch of independent teams. Sometimes, it is more effective to stick to the original one. Same goes for applications.

When an application is not particularly complicated, the size of a development team is small, and the requirements are not difficult to predict, a monolithic architecture will be a better solution. Everything being packed together may help with development, testing, and deploying.

In case of more complicated applications, the necessity of scaling various services independently, or the involvement of multiple teams into the development process, it may become obvious that microservices should be used.

The key is not to choose microservices just because they seem to be more up to date. Use that architecture which helps to solve existing problems but does not create new ones.

What About Legacy Application Modernization?

Consider the case when this company has been operating for several years. The processes, teams, and responsibilities have changed; however, the initial structure of the company supports all operations. It is impossible to rebuild the company from the ground up, as the company needs to continue its work.

The same applies to legacy applications modernization.

Modernization of legacy application does not necessarily imply replacing the whole legacy application by microservices. At times, it makes more sense to modernize gradually, identifying the elements of the legacy application which cause the most issues and isolating them, using new technologies where appropriate.

This way, it is possible to reduce the risks associated with modifying the existing application while leaving the possibility of future development.

Application modernization is not about making the application modern. It is about making it more flexible, scalable, and easy-to-support.

Conclusion: The Right Architecture Is the One That Fits

A maturing business organization does not alter its structure simply because there exists a popular one. A change is required because the current one becomes an obstacle to progress. Likewise, applications should be treated this way.

It is impossible to have a universally winning model in the case of monoliths versus microservices. Monoliths could be the initial option for a small application whereas microservices might be justified by more complexity, size, and team requirements. If we speak about an existing solution, maybe a smart modernization process should come first instead of creating something new from scratch.

We should not think of following any architectural trend; we need an application that can cope with our business. Could use some assistance in defining your application architecture status? We can help you with that.