Who should consider migrating to microservices?

The microservices-based approach produces a type of architecture that drifts from a traditional monolith approach to a more spread out and unit-focused philosophy. Favoring flexibility and scalability, it might be a perfect solution for companies that want to bring their system to the next level fast and with a fairly low entry barrier. Of course, one size doesn’t fit all. So it’s always good to keep in mind the use cases and limitations when implementing any strategy. That being said when applied correctly, microservices can become a key component of a company’s growth. 


Why you should care about microservices


When talking about scalability it is crucial to consider how you want to incorporate additional functionalities to the pre-existing system. The key here is to do it in a way not to overhaul the monolith completely. It gets more and more difficult to do the more you want to develop your system. With the microservice approach, additional instances of particular services can be combined into the system depending on the current load. The same goes for removing services on the fly. This way resource allocation management can be way more efficient. In addition to that, it’s a much more time-efficient solution as multiple teams can work simultaneously in a single software project without stepping on each other’s toes. This leads to faster development and higher overall scalability.


So, the great thing is that you can start your migration right away. This architecture allows for building new functionalities outside the monolith, granted that a good architecture approach is crucial not to create a distributed monolith in the process. But when done correctly it allows for adding new functionalities without rebuilding the entire system, making it a very low entry barrier solution. Another approach, in the opposite of adding new functionalities on top of the pre-existing system, is migrating it chunk by chunk to microservices, decomposing the system gradually until it’s no longer monolithic and completely turns into separate units. No matter which model you will choose, you will see the immediate benefits of lower maintenance costs and shorter release cycles.

Independence is the key here since each microservice is an autonomous unit and can be treated as a separate peace of software that can implement one domain model like notifications, cart, pricelist, document generation, etc. Granted that separate functional elements can be developed independently from each other, but there also needs to be an established contract between other microservices to ensure proper communication within the system. This loose coupling of individual elements means that implementing new changes to the system doesn’t need to cause as many issues of regressions to other parts of the application as in doing the same with a monolith. Since each microservice can be developed and implemented independently of one another, developers always have the option to use the best possible technology for the task at hand. Independence of elements brings on board one more unique advantage. The entire system is way more resilient. If one thing goes down that means that only part of the functionality stops working and doesn’t bring the entire system along with it. That’s something that can’t be achieved with traditional architecture.


The speed of the delivery is another factor unique to this kind of architecture. This is due to the small size of individual services. That way it is much easier to complete development and testing procedures before releasing a new version. Additionally, this arrangement makes it much easier for multiple teams to work simultaneously to deliver and implement additional functionalities. All of this adds up to much shorter delivery time for new functionalities and bug fixes.


Start-ups scaling up their product – and business in the process


Rapidly scaling up their business is a number one concern for many start-ups after developing the first version of their product. One of the key steps to do so is by developing version two of the system. Choosing the right technology – and architecture – might be the main success determining factor. That’s why many companies choose microservices as the architecture base for moving their monolith to V2. A monolith architecture is often a hustle free way to develop a first version of the product. It requires less effort than other approaches and allows for shorter MVP time-to-market. After establishing if the product is gaining enough market traction and financing is available, scaling the product effectively and fast becomes critical. That’s when more advanced architecture solutions come in and microservices are by far most effective of them all. They allow delivering more in a shorter amount of time, by allowing to develop additional, different functionalities separately from one another. This means different teams can work independently from each other developing different solutions and then adding it gradually to the pre-existing monolith. 


 This way of thinking is especially valid when it comes to performance-sensitive online products. Whoever is thinking about scaling up their product, especially if they want to do it rapidly, must consider the amount of traffic that their system can handle. So designing the appropriate architecture from the very beginning. Since each microservice scales horizontally with ease it makes it so much simpler to increase capabilities for systems getting large traffic either on a regular basis or in form of spikes. Incorporating microservice-based architecture into the development strategy of extending the functionality of the system is a low entry barrier solution for scalability since you don’t have to redesign the entire monolith from the ground up. You can simply add new solutions on top of existing code and immediately start benefiting from the improved performance of the new functionalities. This allows for much better product scalability without the need for rebuilding the entire system.


Business scalability is one of the major things that brings investors to start-up companies. A well designed, highly scalable company with ideas based on detailed market research attracts investors and brings capital. A well-rounded product with equally well-designed scalability potential is a crucial part of every tech business model. At the core of every piece of software is its architecture. That should allow the product to reach its full potential in an easy and seamless way. In many cases, microservices are the right solution for this kind of approach.


Mature companies bringing their system to the next level


When your company gets mature enough so that its processes and products start to become more complex it gets harder to incorporate additional functionalities into the bulky system. Especially if you want to do it in such a way that the add-on can be fully integrated with the rest of the system without the need to shut it down for a while. Microservices allow for the implementation of new functionalities to the pre-existing system without the need for a complete overhaul. As a result, customers can immediately benefit from the new functionalities, added on top of the old system. That is why many corporations rely heavily on microservices for adding new functionalities into their global systems. That way millions of users all over the world can utilize the newly added service right away as it is seamlessly incorporated into the core system.


After adding new functionalities into the old system a natural step forward is migrating the entire system to microservice-based architecture. This ensures that the “new” system will be future-proof, more flexible and prone to changes as new functionalities and needs emerge. Usually, an entire plan is being established on how to migrate the system to microservices chunk by chunk. It needs to be established which units need to be migrated first, which could be replaced with new services and which might be skipped altogether. However, before proceeding with the migration, a comprehensive system architecture review is needed to make it microservice-ready. Granted that not all systems can be migrated into microservices, or even if they can, it really doesn’t make sense. This is especially true with very old systems, that haven’t been modernized over the years and right now no one really knows how they work. Or it has a very limited user base so it doesn’t make economic sense to invest in it. In that case, it might be reasonable to remove such a system entirely and rebuilding it from the ground up using more modern architecture. Or simply add on top of it additional functionalities with microservices. That’s what makes this kind of architecture such a universal tool in augmenting various systems.


And that’s that versatility that makes microservices a unique tool ready to take almost whatever you throw at it. You can leverage them to completely redesign your old, bulky system bit by bit. But you don’t need to. You can just add new units on top of the pre-existing monolith, if that’s what makes the most sense at the moment, and continue to do so as you go. This distinct set of features is what brought global organizations like Autodesk or Red Cross to microservices as a part of their international strategy. You can read more about that here.


Moving from monolith to microservices – doing it the right way


Whenever companies, no matter large or small, start thinking about moving their system to a microservice-based architecture, there’s some prep work that needs to be done before they start. So first thing’s first. Even before you start designing your architecture you need to map out your domain and understand its boundaries and shortcomings. There’s a good chance, especially if our system is overblown, that it’s not comprehensive enough in its current form and a well-performed mapping will make it easier to understand its structure. Only after properly mapping the system you can start to design the new architecture. And if you plan on the coexistence of monolith and microservices for some time, the new architecture must be compatible with the monolith, that the two worlds can effectively communicate. 


When diving into microservices take one step at a time. Design a platform and infrastructure required to run the microservices, as they need a more advanced approach to deploying and monitoring. Most often, microservices are deployed on container orchestrators like Kubernetes, Docker Swarm or Mesos, which provides a lot of flexibility in defining how the services are going to be deployed, run and monitored. You can also consider using service mesh frameworks (e.g. Istio, Conduit), that allow for a lot of useful configuration settings that are very useful for microservice projects.


You can take one of the two paths when starting your microservice journey. 


Firstly you can peel off one of the components of the existing monolith. Pick the one that can be easily cut off and moved to a separate service. And then gradually continue to decompose chunk by chunk the entire thing to migrate it completely into microservices. 


The other route is to build new functionalities with new microservices on top of the pre-existing monolith. This kind of approach keeps the old system intact and builds a new infrastructure around it. It’s especially a good way to go when your current system is somewhat bulky or kind of old and it’s not entirely clear how exactly it works. In such a case, often it seems to a good idea to build the new functionalities around the monolith.


No matter which path you will take it is crucial to establish a communication channel. Proper information exchange between the old monolith and a new microservice ecosystem is critical for the whole system to work properly. The recommended way of doing that is to make monolith microservice-aware and have it “play nicely with the new entities. But this is not always possible. It really depends on the monolith’s original structure. 


The first steps are always the hardest. That’s why it is important not to dive head-first when approaching this subject. Let your engineering team learn from their first microservice development. Sometimes it might mean learning from their own mistakes. Allocate some additional time to monitor the code. Revise the key decisions regarding the design and implementation. This will make the proposed changes to the system much more valid. Often when starting a new project we tend to spend a bit more time on things that could have been done at a much faster pace when done in a more mature environment. But that’s really time completely wasted – just lesson learned.

Once the architecture and the approach of developing it have been battle-tested, validated and optimized, that’s when the time invested really pays off. The subsequent microservices can be built at a much faster pace by applying the framework that has been established in the beginning. To make the process even quicker, and cost-optimized at the same time, many companies decide to bring an external team on board. Often the entire process is being offshored to remote/external teams to optimize the transitioning ever further. There are countless success stories of this kind of approach for both startups and corporations.