Scalability in a digital project illustration.

The need to increase web application scalability or launch a product with a corresponding capability from scratch emerges when the audience is likely to expand. The system’s scalability ensures that a web application will resist loads and won’t fail due to the high traffic.

Even if your app is not the second Facebook and doesn’t have to respond to billions of requests daily, it’s worth considering scalability improvement. A powerful server and a stable scalability architecture will enable gradual and consistent system growth.

In contrast, lack of scalability may cause performance failures, leading to audience loss and, accordingly, extra costs spent on attempts to improve resistance.

There are numerous approaches to building scalable web applications. This post will reveal the key steps to creating a scalable web application, drawing on the extensive expertise of the Acropolium team. Also, you will learn the benefits of such a solution, popular frameworks, and examples of successful cases.

Now, let’s go into more details!

Advantages and Features of a Scalable Web Application

Before revealing how to create a scalable web application, let’s figure out what is special about such a product and when it’s worth turning to this solution.

What is Web Application Scalability

A simple definition of a web app’s scalability is the product’s ability to withstand greater loads due to the increased number of users.

A scalable app’s architecture is adapted to any significant workload so that the server, databases, frontend, and backend capabilities are equally stable regardless of the traffic ups and downs.

If your web app is about to serve a few hundred users with no prospects of significant growth, scalability might be an unreasonable waste of time and money. However, it’s a must-have for a modern startup or business that is about to increase the number of customers and serve a large audience’s needs.

Read also: SaaS app architecture best practices.

Benefits of Building a Scalable Web App

Lack of scalability may result in particular challenges if you don’t consider it when building an application from scratch. Whenever your web app experiences higher traffic or expands its capabilities, it might cause a loading speed decrease.

Moreover, you might need to handle constant system errors and crashes. At the same time, any changes you implement to the code and architecture cause the system’s downgrades.

So if you foresee your website growth and want to prevent the potential issues, consider the option to build a scalable web application from scratch due to its advantages:

  • High performance. For large enterprises and businesses dealing with a broad audience, it’s vital to ensure the app is fully operational. Meeting the users’ needs and withstanding traffic will prevent huge revenue losses.
  • Global access. A scalable web application can serve customers globally thanks to reliable server network solutions.
  • Cost efficiency. The scalable system is often easier to manage and maintain, thanks to cloud solutions. Such services will normally cost you cheaper than in-house hardware and software maintenance.
  • Reliability and security. Cloud migration and multiple servers solution, with database replication and sharding, provide confidence in network security. Additionally, the system instantly recovers if anything goes wrong.
  • Increased loading speed. One of the main causes of the users’ frustration is poor loading speed, forcing them to wait for their requests to be processed. Application scalability enables a shorter rendering time, leading to customer satisfaction and increased revenue.
  • Room for improvements. Any changes you make to expand the system and add new features may affect its performance if your web app isn’t scalable.

Web application scalability illustration.

Scalable Web App Architecture

Many people mistakenly believe that creating a scalable product is critically different from any other development process. However, the difference lies in the details.

Building a scalable web architecture is the key to success. Implementing core components to its structure will ensure you won’t have to rebuild the application or rewrite the code when the need to improve performance occurs.

Here are a few main factors to consider when building a product with the potential to expand its capabilities.

An example of a typical web app architecture.

Frontend Architecture

The web architecture’s front-end component directly interacts with the users and represents a user interface template with all its features.

In a scalable web application, the frontend’s efficiency entirely depends on the reliability of the backend. However, a few techniques allow strengthening the front side of your app. In particular, Content Delivery Network enables delivering heavy content to multiple locations via numerous servers. Thus, the end-users will be satisfied with the loading speed regardless of where the requests come from.

Backend Architecture

The backend infrastructure is the core of web application architecture. It is related to all server-based operations, ensuring that the app’s frontend side works efficiently, the requests reach the database, and the users get a timely response in the browser. The backend system is the basis for interaction between the users and the app.

That’s why most of the performance issues are backend-related.

Typically, all user requests are operated via a single server, resulting in failure and reduced loading speed.

When such problems start to arise, it’s time to scale the server-side of your app.

You can scale your web application’s backend in two different ways. Raising your server’s endurance is called vertical scaling. Horizontal scaling stands for turning to multiple servers solution.

Now, let’s drill down the difference between these two approaches.

Scalable server illustration.

Vertical vs Horizontal Scaling

As mentioned above, vertical scaling involves enhancing the server’s, engine’s, and nodes’ capabilities to increase the application’s performance and thus improve its scalability. This approach is quite efficient for solving temporary issues.

However, in many cases, vertical scaling won’t prevent performance challenges of your web app in the long run. Another drawback of this solution is that it doesn’t provide any alternative backing options in case of the system’s failure.

Another option to develop a robust, scalable web application is turning to horizontal scaling. It involves adding more servers and nodes to your system to increase efficiency and reliability. Multiple servers will allow you to distribute the queries and thus reduce the load, eliminating the pressure on a single server.

Moreover, a horizontal solution provides your system with backing options. If some part of your backend can’t handle the traffic, the entire system won’t crash.

Microsoft Azure web application architecture.

AWS web application architecture.

Database Scaling

Database scalability is another essential component to provide high performance of your web application.

Due to increased data volume and multiple simultaneous requests, the database can be difficult to manage. You can turn to the computing processes distribution like replication and sharding to address this issue.

These methods will help you split segment data and deal with copied information, significantly reducing the pressure on the central database.

Replication enables making database copies and processing certain parts of requests through the network. With its help, you will ensure data recovery and boost read performance.

Sharding involves distributing data via multiple databases to respond to some part of the queries. Thus, you can add more nodes when the number of users increases.

Multitier App Architecture

Multitier approach is often implemented to build a large scale web application architecture. Normally, it consists of three separate modules:

  • The client-side server.
  • The application server.
  • The database server.

These three components are physically separated into three different modules. Each of them strives to reach the highest level of efficiency. Every layer conducts its basic functions and isn’t overloaded with any extras.

In particular, client-side modules are preliminary focused on serving the users’ direct needs, making operations easy to perform and intuitive.

In turn, the database server runs its basics, including data processing and granting access, not coping with static and middle-dynamic content.

Such an accurate distribution allows scaling web applications consistently, providing interactions, and keeping the app’s architecture balanced.

An example of a multitier scalable web application, consisting of three tiers.

How to Create a High-performance Scalable Web Application

Keeping in mind the reliable app architecture strategies, let’s specify the key steps and efficient practices commonly used for building scalable web applications.

Define Your Goals and Expectations

Before deciding to scale or not to scale your web app, ensure your goals and expectations require this solution. Building a scalable web application from scratch is quite a complex task to achieve, so you should ensure the funds and resources investments will be worth it.

When making the final decision, consider the following:

  • Web application scalability is crucial for a big project that experiences high traffic loads.
  • Scaling your app makes the system more complex and multilevel, especially if you don’t turn to service providers.
  • Business and market research should prove the necessity to design a scalable web app. Scalability is not just a modern digital trend but a necessity for large enterprises and fast-growing startups.

Monitor the Key Metrics

The most efficient way to determine if your web application needs scaling is through metrics and KPIs. Thus, you can define if your product experiences any performance challenges and which aspects you should improve.

These are the key metrics regarding the app’s scalability:

  • CPU (Central Processing Unit) usage displays the percentage of CPU utilization over time.
  • Network Input/Output shows the number of input/output operations generated by network processes that are neither reads nor writes.
  • Disk Input/Output measures active disk input/output time in KB/s, including read or write operations.
  • Memory utilization estimates average utilization statistics based on available memory percentage over time.

A pie chart displaying core scalability metrics.

Turn to Cloud Computing

You can benefit from cloud-based services that offer options to improve the web app’s scalability for a reasonable price. Platform-as-a-Service (PaaS) providers like AWS, IBM Cloud, Heroku, Microsoft Azure, etc., offer various services related to modernizing and stabilizing the infrastructure. They include networking, integrations, databases, secure storage, servers, etc.

Turning to a trustworthy cloud service provider will save you a lot of time and effort while improving your online platform’s manageability and performance.

Moreover, you can take advantage of certain automation processes like autoscaling. It can significantly decrease manual work and ensure scaling your app up and down when necessary.

Platform-as-a-Service (PaaS) illustration.

Read also: How to reduce cloud costs for your project.

Take Advantage of Microservices Architecture

As mentioned above, scalable web application architecture is the core of successful scaling.

Here are two basic tips to help you make the right choice based on your particular case.

  • Prioritize the horizontal approach. We’ve already described how horizontal architecture can bring reliability to your system. Multiple servers will enable distributing the load and providing extra fallback opportunities. Also, they don’t restrict the scalability prospects.

  • Use microservices architecture. Instead of building a monolithic structure that involves a single code hosting platform, you can apply microservices. It means that your web application’s architecture will consist of multiple independent modules, making them easier to build, deploy, and scale. According to the DZone report, 64% of the surveyed companies adopted microservices architecture to improve their apps’ scalability.

Microservices architecture illustration

Choose the Right Database Solution

The right database selection is another integral component of designing scalable web applications. This choice will depend on what kind of data should be stored.

If you need to store relational data, you may use MySQL, Microsoft SQL, or PostgreSQL database management systems. For non-relational data, turn to scalable NoSQL databases like MongoDB or MariaDB.

To improve efficiency and reach better scalability, you can combine SQL and NoSQL databases.

Read also: Backend as a service: intro guide.

Use the Best Scaling Methods

The following practices are essential for building scalable web applications. Stick to these techniques to ensure your app’s high performance.

Independent Nodes

Following microservices architecture principles, separate your web app’s features and nodes into multiple modules. This approach will allow you to manage each node individually, expand the app’s functionality, and avoid contradictions between nodes and functions.


Cache configuration is the most typical way to handle the rising queries. The caches may be placed in each requesting node, or you may use a global cache. It will instantly allow finding information without overloading the database. The temporary memory will constantly be updating, storing the frequently requested data only.


Proxy servers provide a smoother gateway between users and the Internet. You can use them to coordinate requests on your multiple servers. When combining proxy and caches, you can accelerate the response time and unload the database to improve performance.


Load balancers are used to increase the efficiency of traffic distribution. When the number of requests per minute grows, balancers redirect them to numerous nodes. It will facilitate the routing traffic between users and servers.


Queues may come in handy when the users waste time waiting for a response to their requests. Commonly, a customer cannot complete any operations in your web app until it responds. However, a queue solution enables users to do something else and regularly check whether the system has processed the request.


Indexing is used for efficient database management. Indexes are kept as a dataset informing about the location of certain data pieces. It’s especially useful if you have multiple servers and engines. The more devices you add, the larger the data table becomes. So when a request comes, indexing directs it to the right place instead of searching it throughout the whole database.

Select Robust Technologies

Choosing the right technology to make a scalable web application is critically important. Among dozens of the existing options, you need to opt for the one with certain capabilities.

The chosen tech stack should be suitable for scaling, have a sufficient developers’ community, and completely match your product’s functional requirements.

Below, you will find the most popular technologies for scalable web applications.

Choosing the technology for your product illustration.

The Most Popular Scalable Web App Frameworks

Here are the most probable technologies to choose from if you want to create a scalable web application from scratch.

Read also: Most popular backend frameworks.

Java Spring

Spring is a popular Java framework with an impressive developers’ community. It can perform various tasks, including data processing and security. Spring technology is a great option for those who prefer the Java ecosystem and create a scalable web app. In particular, this framework enables building microservices architecture.

Another great advantage of the Spring framework is reliable documentation and support.

Java Spring
Well-established documentationComplexity
Support provided by the OracleDifficulties in learning
Huge developers’ community
Flexibility and reliability

Java Spring web framework logo.


Node.js is one of the most popular options for scaling your web application. Not surprisingly, it’s used by the giants like Netflix, Walmart, Paypal, etc. This framework significantly facilitates processing requests and balancing the load. It offers many features to improve a modern web app’s scalability. To name a few, these are a cluster module and an event-loop mechanism.

Additionally, Node.js technology is extremely efficient in applying microservices that allow scaling your app up and down with less effort and spendings.

High level of scalabilityPoor library support
Well-established performanceUnstable API
Caching optionsLacks heavy CPU-tasks performance
Multiple functions for processing requests
Simple to learn

Node.js web framework logo.


Django is a Python-based programming language gradually increasing in popularity among developers. This framework is majorly used for building web applications. The main advantage of Django technology is the great variety of functions, including free API, URL routing, database migrations, etc.

Besides, Django is the preferred solution for modern advanced technologies like IoT, AI, and Machine Learning. It’s also widely used for large web apps development.

The downside of Django is its monolithic files structure and inability to cope with multiple simultaneous requests.

Numerous functionsMonolithic files structure
Advanced development capabilitiesMultiple simultaneous requests incapability
Faster developmentLack of conventions

Django web framework logo.

Ruby on Rails

Ruby on Rails (RoR) is another popular choice for scalable web app development, used by Shopify, Airbnb, etc. This technology is based on the principle that combines model, view, and controller. RoR is famous for its time-efficiency and impressive bunch of useful functions. Its libraries include many helpful tools to improve your code when required.

Among the drawbacks of the RoR framework are relatively longer performance time and lack of flexibility. It takes more to process numerous simultaneous queries if compared to Node.js.

Time-efficiencyLack of flexibility
Rich libraries and helpful toolsLonger performance time
Active community
Easy to learn

Ruby on Rails web framework logo.

3 Examples of Successful Scalable Web Applications

Let’s take a look at three impressive examples of successful web applications that managed to scale and lead the market.


Shopify is a famous Canadian eCommerce platform used by more than 1.7 million clients globally. Online retailers can use its marketing, payment, shipping, and customer service tools with this platform. Shopify allows its clients to start a business or move the existing one online.

Shopify, an example of a successful online eCommerce platform.


Walmart is an American retail corporation operating a huge hypermarkets chain and stores. Its history dates back to 1945. The fact that Walmart is the biggest retail enterprise in the world helped it rapidly build and scale its online platform, capable of competing with web giants like Amazon.

Walmart, one of the biggest and oldest retail corporations that successfully started an online business.


Dropbox is a world-famous file hosting service. It’s especially famous for secure file storage, efficient collaboration options, and multiple features that serve numerous business needs. Currently, the Dropbox platform has almost 15.5 million users around the world.

Dropbox, a great example of a scalable web application.

Build a Scalable Future for Your Web Application

Scalability is not just a fashionable trend. It has become an essential quality of modern web software, especially for large enterprises handling large traffic loads and serving huge audiences. If this is your case, you need a robust solution that will include high performance, reliable databases, stable servers, and powerful architecture.

Creating such an application will ensure you can overcome increasing traffic challenges, withstand the competition, and satisfy your users, converting these benefits into revenue.

Hopefully, our guide on how to build a scalable web application helped you realize the value of such solutions and get useful insights. But if you still have any questions related to the topic, we at Acropolium are always ready to give you a hand. Our team has rich experience building scalable apps from scratch and modernizing the existing web products. Get in touch to have a consultation with our experts. Let’s scale your business together!