A 10-Step Guide to Migrating From Monolith to Microservices Architecture
Introduction
Netflix was one of the pioneers in migrating from a monolithic to a cloud-based microservices architecture. In the early 2000s, Netflix faced a significant challenge as its customer base snowballed, straining its IT infrastructure. To address this, the company made a pivotal decision to transition from private data centers to the public cloud and upgrade from a monolithic to a microservices architecture.
This successful shift from monolithic to microservices marked Netflix as a trailblazer in the industry. Today, nearly all tech giants like Google, Twitter, and IBM, have moved to the cloud, while other companies are gradually starting their migration.
Monolithic apps are self-contained systems where the user interface, code, and database exist in a single platform. Unlike modular apps, which allow for individual updates and maintenance, monolithic apps pose significant challenges regarding scalability, maintenance, deployment, etc.
On the other hand, Microservices architecture builds apps that follow a modular design. Modernizing applications enhances scalability, maintainability, security, performance, and innovation, ensuring compatibility with evolving technologies and keeping businesses competitive.
Whether you’re a startup, small, mid-sized, or enterprise-level company, microservice architecture suits all. Implementing modern trends in microservices—like serverless solutions, Kubernetes orchestration, containerization with Docker, and CI/CD pipelines—can help develop future-ready applications.
The following write-up discusses the basics, benefits, and step-wise implementation. Read to the end to learn how to plan a seamless conversion.
Understanding Monolithic and Microservices Architectures:
Let’s understand the specifics of monolithic and microservices architecture.
1. Monolithic Architecture
As the term implies, monolithic architecture is a single-tiered traditional software model with multiple components, such as business logic and data, in one extensive application. Therefore, updating or changing one component requires rewriting other elements and recompiling and testing the entire application.
2. Microservice Architecture
A microservice architecture uses loosely coupled services that can be created, deployed, and maintained independently. Each component is responsible for conducting discrete tasks, and they communicate with each other using simple APIs to attend to more significant business problems.
Why Modernize a Monolithic Application?
Applications today demand scalability and all-time availability. These requisites are best addressed with a monolith to microservices migration.
According to a survey from Mordor Intelligence, the cloud microservice market is predicted to grow at a CAGR rate of 22.88%, from $1.63 billion in 2024 to $4.57 billion in 2029. The need for low-cost drives this shift, as do secure IT operations and the adoption of containers and DevOps tools.
Here are the challenges of monolithic apps and the need for modernization:
- Monolithic applications are complex and costly to scale due to their interconnected nature.
- Updating a monolith often requires downtime and can compromise system stability.
- Monolithic architectures hinder the adoption of new technologies, impacting competitiveness.
- Outdated technologies limit the functionality and scalability of your application.
- Users prefer fast applications; falling behind technologically can cost you customers.
- Maintaining apps built on old tech stacks is difficult and costly due to outdated programming languages and scarce expertise.
Advantages of a Microservices Architecture
Here’s a list of some tactical and technical benefits this transition offers.
1. Business Agility
Incorporating microservice architecture makes your system easily adjustable, offering independent components. It helps you adhere to your business needs with less effort while adding, removing, or upgrading features, offering a competitive advantage.
2. Rapid Deployment
With a centralized database, the code used by microservices is more understandable. Changing the code becomes effortless for teams as they can quickly access the dependencies. This saves more time and resources while deploying upgrades.
3. Higher Productivity
Reduced dependencies and independent components allow teams to create, scale, and execute numerous microservices simultaneously, offering more freedom to developers. For example, they can make the best products or services by selecting the coding language, frameworks, and APIs that align with their goals.
4. Resilience
In monolithic applications, modifying one module can disrupt the entire system. In a loosely coupled architecture like microservices, each service isolates its errors, minimizing their impact on the overall system. This shift from monolith to microservices enhances system resilience by reducing the risk of widespread failures.
5. Enhanced Scalability
The best part of microservices architecture lies in its ability to scale individual services independently based on demand. This means that resources can be explicitly allocated to the parts of the application that need them most.
6. Cost Efficiency
Microservices help minimize infrastructure costs by efficiently using cloud resources, scaling as required, and aligning operational expenses with actual usage patterns. Together, these aspects make microservices a cost-effective choice for modern applications.
Tech Giants That Have Adopted Microservices
Many known names have efficiently applied microservices architecture. Here are three examples of those leading institutions.
1. Amazon - Microservices and Agile DevOps
Initially, Amazon’s two-tier architecture required a lot of time to develop and deploy new features or map changes in code. Amazon embraced microservices to enable independent development and deployment of services through standardized web service APIs.
This architectural shift allowed Amazon to scale its operations significantly, making approximately 50 million deployments annually, successfully clinching the title of the world’s largest e-commerce marketplace.
2. Uber - Microservices Decoupling
Uber started with its services limited to the city of San Francisco. A single code base encapsulated features such as invoicing, communication between drivers and passengers, and payments.
As they observed eventual success, Uber switched to a microservices architecture to discard the dependency amongst the application's components.
3. Spotify - Autonomous Microservices Teams
Spotify adopted microservices to address scalability challenges and to enhance its ability to innovate and deploy features quickly in a competitive market.
By adopting microservices, Spotify achieved enhanced scalability and innovation agility, which is crucial in a competitive market that serves 75 million active users monthly. This architectural shift empowered autonomous, full-stack teams to independently develop and deploy features, minimizing dependencies and streamlining operations across multiple global offices.
10 Steps to Conduct a Strategic Monolith to Microservices Migration
Migrating from monolith to microservices architecture is arduous and can result in numerous compatibility and performance issues. Here is a 10-step process that presents a well-rounded approach to maneuvering this transition.
Step 1: Define Your Desired Outcomes in Detail
A successful migration requires myriad prerequisites, including your present infrastructure, the team’s technical proficiency, and internal strategy.
Let’s observe the essential pointers that demand undivided attention.
- Prioritize your goals, like improving scalability, uptime, or innovation, to calculate the efforts and approach required.
- Ensure all deployments, from servers to network components, meet performance standards.
- Scrutinize your service-level agreements (SLAs) for commitments you can adhere to.
- Monolith to microservices migration is a collaborative effort. Invest in tools to help team members share concerns while offering them freedom.
- Aim for a loosely coupled architecture to experience independence when creating, updating, and deploying features.
- Keep tools and backups in place to handle failed deployments.
- Maximize organizational efficiency by inculcating an acute understanding of DevOps services and principles.
- Implement new systems with stringent security measures, such as API gateways, communication protocols, and firewalls.
Step 2: Learn Hidden Dependencies
It can become challenging to manage if a payment service's code connects with external payment providers, loads unnecessary libraries, or interfaces with outdated processes.
Monolithic apps can possess complex code structures that are difficult to comprehend, resulting in hidden dependencies. A revamped approach to this problem is clearly understanding your core functionalities and business needs.
All microservices should serve a single purpose with a dedicated data repository. This eliminates the possibility of redundant applications offering similar features or conflicting data from different sources.
Step 3: Seek Input from Technical/Non-Technical Teams
It’s essential to determine which functionalities offer the best value when transitioned to microservices and which are suitable for monolith architecture.
After deciding on the above needs, one must seek inputs from both technical and non-technical teams. Technical teams can share their knowledge with dependencies, existing systems, and internal events. Non-technical teams can highlight gaps in present systems and features, sharing insights on futuristic developments.
For example, features of a payment service group that observe the transition to microservices are authorization, refund, cancellation, and status checks. However, it can continue with monolith systems with functionalities such as order status, package tracking, and inventory checks.
Step 4: Migrate Independent or Essential Features First
All features are unique to an application. However, some independent features don’t rely on or affect other system parts, such as managing orders, sending notifications, or invoices.
Another reason to migrate an independent feature is to solve a specific problem. If a system’s functionality is slow or compromised, it can be converted into a separate microservice to enhance performance.
Step 5: Opt for Scalable Cloud Infrastructure
Cloud platforms offer easy scalability through autoscaling, and you only pay for what you use. Additionally, certified cloud providers like Google Cloud, Microsoft Azure, and Amazon Web Services offer security features to safeguard customer information and data. These service providers also provide maintenance services.
Step 6: Leverage APIs to Manage User Requests
Imagine a big Lego castle with huge pieces. Tearing down a monolithic application is like reassembling these big pieces with smaller, manageable pieces. Monolithic applications have three main layers.
- The presentation layer is what users interact with.
- Business logic is what handles main tasks and decisions.
- The persistence layer is where all the data is stored.
To cohesively connect these layers, a ‘traffic controller’ known as a ‘gateway API’ is required. A gateway API sends user requests to their desired microservice and back again. It keeps different systems on track, preventing them from getting tangled up while adding security layers like data authorization. It also prevents system overload by managing user requests.
Step 7: Effective Interaction Between Services
Effective communication among different services is important in a loosely connected system. Two methods exist for managing inter-service communications.
- Synchronous communication: The caller waits for a reply.
- Asynchronous communication: The service can send multiple messages without awaiting a reply.
As more of your applications observe a transition to microservices, it's best you switch to asynchronous messaging.
Your team must also set up proper public and backend APIs for client application calls and interservice communication. A public API should work cohesively with your mobile and web applications, while factors such as data size, network performance, and responsiveness should be considered when choosing backend APIs.
A preferred choice for client-side APIs over HTTP/HTTPS is REST.
While for server-side APIs, one can use:
- RESTful interfaces: Good for stateless communication and easy scaling.
- RCP interfaces: Recommended for handling specific commands and operations.
Step 8: Transfer Legacy Databases
Once your communication channels run, it’s time to migrate your data, logic, and features to your microservice systems. Transferring all information on the go might not be possible and may require a phase-wise approach.
However, this process needs an API that acts as a bridge. This bridge will then grab the old information from the monolithic app and transfer it back to the new microservice, such as a payment service.
Step 9: Create a Dependable CI/CD Process
To reap maximum benefits from this switch, you need a smooth (continuous integration) CI/ CD (continuous delivery) pipeline for microservices. CI upholds your code quality benchmarks, allowing your team to test changes automatically, while CD instantly deploys code changes in real-time.
Step 10: Test Functionalities Before Deployment
Ensure the new setup supports the functionality as intended. You may note many semantic differences between the old and new systems. However, here are some methods to address this difference.
- Leverage glue code, which acts as your bridge between old monolithic apps and new systems. This transfers data essential to your microservice architecture, filtering redundant data that can compromise your new system.
- Manage performance issues and errors using the canary release technique with your microservice migration. For instance, initially, direct only 5% of your traffic to new microservices. If they observe an error-free experience, you can map an eventual increase in users reaching up to 100% before making the final switch.
Once you conclude the transition to microservices, you can discard the translation code and old monolith parts. Repeat this process until your scalable architecture is in place.
Maruti Techlabs - A Modernizing Partner
In today’s fast-paced digital landscape, it’s challenging for any business to maintain an in-house development team proficient enough to execute large-scale modernization projects flawlessly. Partnering with an expert is the best strategy when transforming your monolithic application.
With over 14 years of experience and a successful track record of delivering 100+ projects with a net promoter score of 98%, Maruti Techlabs is your ideal modernization partner. We offer comprehensive solutions for modernizing IT processes and infrastructure, addressing challenges such as outdated architectures and legacy application management.
Our process begins with thorough risk assessments and detailed roadmap creation to align with your business objectives. We focus on modern architecture, iterative development, and continuous feedback during the design and development phase. The implementation and migration stage ensures a smooth transition with minimal disruption, integrating leading technologies and comprehensive testing.
Our value-driven approach maximizes ROI through tailored, efficient, and effective modernization strategies.
Conclusion
Businesses today need speed and scalability to stay ahead of their strongest competitors. Conventional monolithic architecture doesn’t offer the agility and convenience that modern applications need. Therefore, it’s inevitable for businesses to avoid making these upgrades forever.
Whether you’re a budding eCommerce chain or an established education organization, customers are central to every business. Treasure Data and Forbes report that 74% of customers are highly likely to purchase based on experience. Therefore, you must design experiences with your web or mobile applications that cater to your customers in the best way possible.
Maruti Techlabs understands the complexities of these transformations. Our cloud migration experts can develop a foolproof roadmap for modernizing your enterprise applications while fully supporting your existing business requirements. Contact us today to discover more about our enterprise application modernization services.
FAQs
1. What are the three types of microservices?
The three different types of microservices include:
- Domain Microservices: Loosely coupled services that use an API to connect with other services to offer related services.
- Integration Microservices: Microservices that allow different types of applications to work together, even if they weren’t designed originally. They are leveraged when using ready-made, off-the-shelf software.
- Unit-of-Work Microservices: An independent service offering a single functionality.
2. How many microservices are in an application?
There are no specific rules regarding how many microservices an application can include. However, a traditional system would have significantly more microservices than three.
3. Which is better, microservices or monolithic services?
A monolithic architecture is better for starting a new project because it offers benefits like easy code management, cognitive overhead, and deployment. However, a microservice architecture offers smaller, independent components that can be updated without compromising other application functionalities.
4. How to break monolithic into microservices?
This change is essential yet challenging. For a successful implementation, one should begin with a minor or necessary service and then opt for crucial business functions that require frequent change. These services should be independent of the old monolith, ensuring all developments enhance the overall structure.
5. How can we modernize monolithic applications?
If you aren’t familiar with application modernization, the foremost task is to create a roadmap.
Firstly, you must fixate on your business goals, where you currently stand, and your expectations with technology to achieve these goals.
It’s followed by learning what your modernization process plans to achieve. To do this, you’ll have to identify your application portfolio against your business and technology goals and determine the apps that require modernization, the best suitable methods, and how to prioritize them.
6. Is it possible to use a hybrid of monolithic and microservices?
Creating a hybrid application that offers the benefits of monolithic and microservices architecture is possible. In a hybrid structure, many services can be designed and implemented as microservices, but the core functionality follows the monolithic structure.
