How to transition from Monolithic to Microservices?


Legacy modernization is one of the most talked about approaches enterprises are adopting to meet their business goals – businesses that evolve to stay relevant in the market. Until recently, the focus for most of these enterprises was to develop applications that are quick to deliver results, not emphasizing much on other attributes such as scalability, modularity, robustness, flexibility, ease of deployment, and so on. This was one of the key reasons why most of the applications followed monolithic architecture, designed to be self-contained with components tightly coupled. While the monolithic applications work well in the initial period, it has been seen that they are unable to meet the growing business demands, resulting in maintenance challenges, low reliability, lack of agility and so on. Scaling up these monolithic applications is quite challenging, and that’s why businesses started looking out for alternatives that can meet their business and IT needs. One of the effective ways they could find to address this challenge was replacing these monolithic applications with smaller, independent services, operating on their own – known as microservices. Microservices turned the monolithic ecosystem into a new, agile world in which developers and operations teams can work together to achieve small, loosely coupled applications that can be scaled up and out, as per the business demands.

The underlying idea of the transition

Microservices architecture is an architecture style in which applications are built by using loosely coupled, independently deployable units. These units are generally grouped based on business capabilities, which helps in addressing the challenges and risks posed by monolithic architecture. While the idea behind replacing the current with next-gen was clear, it was also obvious that the transition cannot take place overnight. It is a journey that needs proper planning, skilled resources and governance for execution.

  • Perform need analysis in terms of Cost vs Benefit. Build proper roadmap, framework & governance
  • Build all new features using Microservices patterns with tweaks to existing Monolithic application where needed
  • Identify existing loosely coupled, high business impact components & start moving them to Microservices
  • Move all existing components into Microservices along with split of original single database into service-specific databases

SLK understands this space and has all what it takes for the transition to happen. We have the domain expertise and skilled resources to help enterprises move away from the legacy or monolithic to microservices. We also enable businesses in identifying which approach would work the best, based on their goals and objectives.

Key tenets of the transition

Transitioning from monolithic architecture to microservices should be done incrementally, after performing the need analysis of cost versus benefits. The key tenets of the transition include –


Start with the disjoining of services within existing application

  • Based on business capabilities or domains, the services should be disjoined
  • Build all the new features using microservices architecture
  • Analyze the existing functionalities and identify the ones that can be loosely, independently maintained and move them to microservices architecture
  • Modify the existing application to send requests to the new microservices


Once the vertical capabilities are disjointed, discharge the data

  • The game plan is to first take off the vertical capabilities from the monolithic along with the data by splitting the original database into service specific databases so that each component can exist as a standalone service with its own set of data
  • Analyze tables and map them to individual databases
  • The tables that are common across services should be made accessible through appropriate pattern
  • Ensure data integrity through joins

User interface:

Design new user interface for the microservices

  • Ensure the new screen design is efficiently designed for newly defined services
  • Make appropriate choice of UI rendering technique based on business needs


Deploy the microservices and get the game started

  • Use the best deployment strategy based on business needs
  • Use “Single service instance per Host” option if the focus is on clear separation of services, and ease of monitoring and deployment
  • Use “Multiple service instances per host” option if the focus is on efficient use of resources

How efficiently the microservices operate in your ecosystem depends on the organization structure. Migrating can be a tedious task, but the benefits these microservices bring along with them can easily overshadow the challenging part. Need help with transitioning to microservices from your legacy applications? SLK has the right tools and knowledge to help you achieve this, in simple and easy manner.

Authored by Sanjeev Jadhav

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