The concept of microservices defines an approach to the architecture of IT systems that divides an application into a collection of loosely coupled services that implement business requirements. In fact, this is a variant of the concept of service-oriented architecture (SOA). One of the most important benefits of a migration to microservices-based architecture is an ability to perform continuous delivery of large and complex applications.
By now, you have probably had an opportunity to read some books or articles about microservices. I think that most of them would have given you a detailed description of their advantages and drawbacks. There are many advantages to using microservices. The first is that microservices are relatively small and easy to understand for a new developer in a project. We usually want to make sure that the change in the code performed in one place would not have an unwanted effect on all the other modules of our application. With microservices, we can have more certainty about this because we implement only a single business area, unlike monolithic applications where sometimes even seemingly unrelated functionalities are put in the same boat. That is not all. I have noticed that, usually, it is easier to maintain expected code quality in small microservices than in a large monolith where many developers have introduced their changes.
The second thing I like about microservices architecture concerns division. Until now, when I had to deal with complex enterprise systems, I always saw that dividing the system into subsystems was done according to other subsystems. For example, telecommunication organizations always have a billing subsystem. Then you create a subsystem that hides the billing complexity and provides an API. Then you find out that you need data that can't be stored in the billing system because it is not easily customizable. So you create another subsystem. This leads in effect to you building a complicated subsystem mesh, which is not easy to understand, especially if you are a new employee in the organization. With microservices, you do not have problems such as this. If they are well-designed, every microservice should be responsible for an entire selected area. In some cases, those areas are similar regardless of the sector in which an organization is active.
