How to build a scalable web application using Microservices Architecture

Author: Sneha Gopal
June 16, 2022
How to build a scalable web application using Microservices Architecture


Millions of people worldwide stream more than two billion hours worth of video from Netflix each month. Another example is Facebook, which roughly had 2.85 billion active users in the first quarter of 2021.

Talking about the e-commerce giant, Amazon receives more than 66 thousand orders per hour, and 18.5 orders per second. Whoooo!

So, how do these organizations manage such a colossal flow of consumers on their websites and apps? How do they enable millions of users to access their accounts, use available functions and perform desired actions without any hassle or downtime?

Well, that is scalability in action for you. Given this dynamic, Facebook, Amazon, Netflix are all wonderful examples of scalable applications.

Scalable web applications can easily cope up with the rising numbers of users. From the application perspective, scalability refers to the capacity to handle the growth. User behavior suggests the minimal amount of waiting that people are willing to dedicate for a process to form, image to load or an application to open.

In the chaotic world of apps, a scalable web application is the king. With rapidly evolving user expectations and market needs, web apps must have the ability to handle a growing number of users or even sudden spikes in demand from a big pool of app/website users.

What does a scalable web application mean?

A scalable web application is designed to accommodate the sudden increase in the number of users and load, irrespective of whether it is a gradual or abrupt peak, without disrupting end-user experience and activities.

Scaling web applications will help you to grow and handle the requests per minute more efficiently. Before scaling web applications, there are some factors that you need to consider like scaling metrics and costs of scaling. These factors are highly determinal in ensuring the feasibility of scaling web applications.

Designed using modern technologies and frameworks like microservices architecture, PWA, caching and cloud storage, a scalable web application ensures that performance remains unchanged throughout the use.

Introduction to the scalable app architecture

The two main principles underlying the scalable architecture design of any software platform are-

Separation of concerns

Separation of concerns elaborates the idea of using separate servers for each type of task. Consider an app in which one server does all the tasks including handling user requests, storing user files, etc. It actually does the job that should be done by several different servers. This negatively impacts the functioning of the entire app as the server gets overloaded. To avoid the same, you must ensure the separation of concerns.

Horizontal scaling

How many requests can a particular server handle? This depends on several factors like RAM. CPU capacity and other specifications. What if there is only one server to handle all the tasks. Once the server gets overloaded, it crashes and the app stops responding until the server recovers.

Horizontal scaling

This is where horizontal scaling comes into the picture. It essentially divides the complete load between several servers. As each server runs a copy of the app, it can be enabled or disabled as per the current load.A special component named load balancer carries out the process of load distribution. With horizontal scaling, you do need to scale the entire application in case of a problem.

What makes an app truly scalable?

A scalable architecture design is expected to meet the below stated criteria. This architecture design is highly detrminal to the success of your scalable web apps. Without further ado, let’s get started.

  • Smooth Performance: The app showcases high performance irrespective of the load or number of users

  • Continuous Availability: It is crucial that the app is available all time even during abrupt peaks.

  • Data integrity: The app’s data consistency is maintained throughout.

  • Malfunction monitoring: Issues are easily identified and addressed

  • Real-time response: This involves fast data retrievals, speed of operations and response.

Scale or Fail- Why is scalability important for your business?

Growth and profitability are common business goals. In this regard, scalability is vital to ensure that a business can sustain the growth it achieved once.

In this digital-first world, consumer preferences and market needs change rapidly. This highlights the importance of a business’s ability to adapt and take advantage of the changing trends. It is a key factor in determining business success.

In the digital paradigm, people want fast web experiences across all business verticals. They want the web pages to load fast, get rapid results,quickly pay bills and so on. As the page load time goes from 1s to 5s, the probability of bounce rate increases by 90%.

Regardless of how many other people are trying to access your online content, users today expect a lightning-fast load time, round the clock availability and minimal user experience disruptions. If your application/website is not designed to be scalable as workload and users increase, then it will be inevitably abandoned.

This is where scalable web applications steps in.

Benefits of building scalable web apps

Scalability is all about handling growth and it is an essential component in your business-critical applications. Prioritizing it from the beginning offers a myriad of benefits including better business agility, reduced maintenance costs and better user experience.

Needless to say,there are many reasons to make the app scalable. Let’s get started

Protect Your Initial Technology Investment

By choosing a scalable solution, you can continue to use the same software for a longer period as your business expands. This is because the software was designed to evolve with your growing business needs.

Give your users the best app experience

As mentioned earlier, your users hate slow apps. Whether it is a purchase, booking a ticket or information searching, he/she just wants to complete the action as quickly as possible with minimum disruptions. And the highly scalable architecture of the apps makes them the best choice for positive user experiences.

Better app performance.

Scalable web apps come with the ability to handle abrupt surges in the number of users or workload without compromising the user experience. This is in stark contrast to conventional apps which slow down due to peaks in traffic.

Continued business growth

With rapidly changing business requirements and market conditions, long-term planning is not a viable option. Scaling your web apps is the way forward in the fast-changing business ecosystems.

Save Money

Scaling business-critical applications prove to be cost-effective in the long run as it helps an enterprise to ensure business continuity even in the most unprecedented situations.

Building Scalable Web Applications Using Microservice Architecture

Monolithic architecture becomes difficult to scale, upgrade or maintain as it grows over time. The growing complexity makes the architecture difficult to modify. Enterprises can overcome this challenge using the microservices architecture.

Implementing microservices architecture offers one of the best ways to build scalable web applications. Microservices architecture helps in the seggregation of large applications to smaller components, with each part having a specific responsibility. The microservices architecture for web application works best for the applications which you wish to scale down.

Unlike conventional monolithic architecture, which stores the entire code in a single code hosting platform while scaling in one dimension, microservice architecture breaks down complex tasks into small processes that operate independently and communicate through APIs.

The decentralized architecture of the microservices divides the application functionalities into loosely coupled, manageable and reusable components. In contrast to monolith architecture, this approach enables organizations to upgrade, maintain, test and develop individual web services without affecting the entire application. Thus, enabling businesses to be more agile.

Results of using microservices architecture to build scalable web apps

  • Scale up or scale out your applications in real-time with minimal disturbance to the end-user

  • Faster time to market

  • Helps overcome numerous scalability issues

  • Speeds up the launch process

  • Enhanced security

  • Shorter throughput and load time

  • Boosts app resilience

  • Reduced downtime

Introduction To Microservice Architecture

Introduction To Microservice Architecture

Microservices are an architectural framework for building applications. What sets apart microservices architecture from the conventional monolithic approach is how it breaks down an app into small and independent units. On the other hand, a monolithic application is developed as a single unit. A web application microservice architecture is designed on the theory that rach individual server is responsible for the assigned unit. Once the app is broken down into core functions, each function is called a service. Each service is-

  • Highly testable

  • Loosely coupled

  • Independently deployable and maintainable

  • Organized around business capabilities

  • Owned by a small team

  • Focuses on a particular task

The services communicate with each other using simple APIs. The architectural style enables developers to build software in a modular way while solving large complex business problems. Java, PHP, Python, NET, Node.js are some of the few technologies used to implement microservices:

Microservices Architecture Examples in Action

Amazon, Netflix, Uber, and Etsy are examples of big enterprises that broke down their monoliths and refactored them into microservices architecture. This approach took their business agility and scaling advantages to the next-level.

What are the different microservices architecture styles?

There are two types of microservices

Stateless architecture

As the name suggests, stateless microservices do not maintain any session state across requests.

Stateful architecture

Unlike stateless, stateful microservices store session information in the code for it to function.

What are the defining features of microservice Architecture ?

Are you excited to know more on how to build scalable web applications? Before that let’s read on to find about the defining features of microservice architecture. to check Microservices has been the buzzword among forward-thinking app development companies since the term was first coined in 2011. Without further ado, let’s explore the features that have made microservices so popular.

#1.Independent Developers

Microservices architecture enables small teams to work in parallel and independently. This enables them to independently build, test and deploy their code resulting in faster iteration.

#2.Agility and Speed

Large monolithic applications built by organizations often pose challenges in modifying or updating the app to meet user requirements. On the other hand, utilizing microservices, teams are able to test and deploy code changes quickly, making them more adaptable to changing customer needs.

#3.Isolation and resilience

With microservices, your entire application is decoupled into services that are independent units. Unlike monolithic architecture wherein an error in the code affects the entire application, using microservices there is minimal impact of the failure on the app.

#4.Improved Scalability

Scalability is a critical feature of microservices. As each service is an independent entity, one can easily scale up or down a particular service without having to scale the entire app.

#5.Lifecycle automation

In stark contrast to monoliths, independent services in a microservices architecture easily fit into the CI/CD delivery pipeline.

#6.Easier debugging and maintenance

Microservices make it easy to debug and test applications. Smaller independent units going through continuous delivery and testing significantly improve a team’s ability to deliver error-free apps.

What are the business benefits of microservices ?

Microservices offer a wide spectrum of business benefits.Here let’s take a look at the reasons you should consider microservices for your next app development project

1.Meet ever-changing customer needs

With the explosion of mobile technology and the always shifting needs of consumers, businesses have to adapt just as quickly as possible. Using microservice architecture enables the fast, frequent and reliable delivery of large, complex applications. This rapid implementation of changes helps organizations meet changing user needs promptly.

2.Use the right tool for the right task

With microservices, you have the freedom to experiment and choose the technology stack (programming languages, databases, etc.) that is best suited for the required service rather than sticking to a one-size-fits all approach. Even with their own language and framework, services are able to easily communicate with each other.

3.Better Fault Isolation

In case of an error in a service the functioning of the whole application remains unaffected. Once the error is fixed, it is deployed for the respective service without redeploying the entire app.

4.Break Down Silos

Microservices is redefining the deeply ingrained IT culture of siloed development and operations teams. The architectural style promotes better team collaboration and communication and eventually prepares the restructured teams for new feature integration, scalability and failures.

Other advantages

  • Higher development velocity

  • Supports iterative development and modernization

  • Enables teams to take advantage of the modern technologies, frameworks and tools like Cloud, serverless, containers

  • Microservices support both granular and horizontal scaling

  • Reduces cognitive complexity as developers have to deal with smaller units of code

What are the Challenges Associated with Microservice Architecture ?

Let us explore the flip side of microservices. What are the disadvantages of Microservice Architecture?

  • Get ready for rapid provisioning and app deployment with incremental development and continuous delivery.

  • Robust monitoring is a must to effectively monitor and manage the entire infrastructure as each service relies on its own language, platform, and APIs.

  • Testing becomes complex with microservices. Each service has its own set of dependencies and as new features are added, new dependencies emerge. It becomes impractical and complex to keep a tab on all these.

  • Keeping the entire infrastructure secure becomes challenging as microservices are often deployed in multi-cloud environments. This results in increased risk and loss of control and visibility of application units.

  • Unlike monolithic,organizations face increased complexity when designing microservices.

  • Increased operational complexity is a reality when using microservices

You are Growing, But Are You Scaling?

The ability to scale is critical in today’s digital world, if you aim to grow your business and broaden its functionality over the course of time. Take your business’s scaling capabilities into account right from the beginning.

Scalable web apps are an incredible choice to augment your business’s scaling capabilities. It enables you to rapidly meet changing customer needs, reduce operational costs, deliver better customer experience and improve customer loyalty.