Monolithic vs Microservices

Strengths of Monolotic Architecture

• Easier Debugging and End-to-End Testing: Unlike Microservice Architecture, Monolithic Applications are much easier to debug and test. Since a Monolithic Application is a single indivisible project, you can perform end-to-end tests much faster.
• Easy Deployment: One advantage associated with the Monolithic Applications being a single piece is easy distribution. Deploying a single part is much easier than deploying dozens of services.
• It is Relatively Simple to Develop: It is much easier to write a Monolithic Application in a modular manner, following the general principles, than to write each module as a service.

Weaknesses of Monolithic Architecture

• Complexity: When a Monolithic Application grows, it becomes too complex to be understood. In addition, complex code structure within an application is difficult to manage, no matter how you follow the principles, the growth of code will always increase complexity.
• Difficulty Making Changes: It is very troublesome to make changes in such a large and complex application. Any code changes affect the entire system, so all parts need to be checked entirely. This can make the overall development process much longer.
• Scalability is Low: You cannot scale components independently. You need to scale the whole application.
• Failure to Apply New Technology: Implementing a new technology in a Monolithic Application is extremely problematic, integrating the application into a new technology means re-developing the whole application. Failure to adapt to innovations can also lead to a loss in many areas.

Strengths of Microservice Architecture

• Independent Components : Each service can be deployed and updated independently, providing greater flexibility. An error in a Microservice only has an effect on a particular service and does not affect the entire application. Also, adding new features to a Microservice application is easier than the Monolithic one.
• Intelligibility: A Microservice application that is divided into smaller and simpler components is easier to understand and manage. It is focused only on a particular service that is related to a responsibility it has.
• Better Scalability: Each service can be scaled independently. Therefore, it is not necessary to scale the entire application. This saves a great deal of time and cost. In addition, every Monolithic Application has limits in terms of scalability. However, multiplying a service with traffic on the microservice is less laborious and able to handle the whole load. This is why most projects that appeal to a large audience have begun to adopt the Microservice Architecture.
• Technology Diversity: Teams do not have to select the technologies that services will be developed completely, so over time they can choose the technology that suits them. For example, a service can be developed with the Python Programming Language to use the Machine Learning features next to the Microservices developed on Java. The desired technology or database can be used for each Microservice.
• Higher Agility Level: Any error in a Microservice application affects only a certain service, not the entire application. Therefore, all changes and tests are carried out with lower risks and fewer errors.
• Reusability: A service you have developed independently can be used in another project with minor changes depending on your needs. For example, “User Management” service has similar responsibilities and functions in almost all applications and perform similar tasks. You can position this service directly in another project and use it. Thus, the time and cost of developing a service can be saved.

Weaknesses of Microservice Architecture

The statement that everything has a defect is valid here as it is in everything else. Although I will mention in my next article, Microservice Architecture should never be preferred for small and small audience applications.

• Extra Complexity: Since a Microservice Architecture is a distributed system, you need to configure it separately for all modules and databases. Also, as long as such an application includes independent services, they must all be deployed independently.
• System Deployment: A Microservice Architecture is a complex system of multiple services and databases, so all connections need to be handled with care. Deployment requires a separate process for each service.
• Difficulty in Management and Traceability: When creating a Microservice application, you will need to deal with multiple situations. Environments, where external configuration, metrics tracking, health-check mechanisms, and Microservices can be managed, are required.
• The Difficulty of Testing: A large number of services deployed independently make the testing process very difficult.

With all these in mind, keeping up with the developing technologies will be the right thing to do. If we will develop medium and large-scale applications that appeal to large audiences, Microservice Architecture will be one of the most suitable choices without ignoring other criteria. If it is applied correctly, you can take advantage of all its advantages and feel the flexibility, scalability.