The digital era offers unparalleled possibilities for business growth, with fast-growing start-ups often scaling up to $10 million in less than five years, according to Deloitte. However, skyrocketing to popularity is not enough – enduring the growing demand is equally important. The key to success is scalability – the ability of a service to remain operational under increasing load. To help you make your success sustainable, here are some insights on how to build scalable web applications based on our team’s experience.
What Is a Scalable Application
In the simplest terms, scalability is the ability of a system to perform well under increasing workload. In the case of a web app, this means delivering excellent user experience during activity peaks. This is achieved in a variety of ways, from adding resources to handle the additional load to improving the ability to restore after a failure. In any case, to achieve scalability the developer has to build a web app with growth in mind.
How to Measure Scalability?
From a technical standpoint, scalability can be measured by specific procedures such as a ramp-up test, which identifies at which point the intensity of the workload will start causing issues. However, while running a test is more or less straightforward, predicting the expected load on the service is tricky. Not only is it hard to predict how fast the business will grow, the load will probably fluctuate based on a host of factors. Sometimes, a single mention in a social media post can grind your website to a halt. Besides, depending on the application’s purpose, workload can refer to different things, like the number of simultaneous visitors, maximum storage capacity, or the number of handled transactions.
So, rather than focus on specific metrics, scalable web app development should be based on these three properties:
- Performance: How well does the app perform under the highest possible load and what can be done to raise this bar
- Recoverability: Once the app malfunctions, how long does it take to return to the operational state and whether something is lost in the process
- Serviceability: How difficult it is to maintain the app in a working state, introduce new features, and update the existing ones
As long as these conditions are fulfilled, you have a solid foundation for a scalable app.
Why Are Scalable Web Apps Important?
While the digital-first approach opened up many opportunities for businesses, it also raised the expectations of the audience to an unprecedented level. Nowadays, users want nothing less than a stellar experience and will happily leave your service in search of a better option even after the slightest disruption. Surveys continue to show that the majority of users hold apps responsible for performance issues and use problematic services three times or less. Fortunately, the opposite is also true – fast loading times can have a considerable positive impact on a company’s revenues.
In this light, scalable web apps offer several benefits for businesses:
- Positive user experience: Your customers will associate the service with the company, so a positive experience of engaging with the service will contribute to a favorable brand image.
- Financial performance: Fewer setbacks in your platform’s performance mean more customers serviced and, by extension, steadier revenue streams.
- Cost savings: Repurposing a non-scalable web app for a larger audience can be done later but would require much more resources.
- Higher ROI: Software development process is costly, and unless it creates value for your audience, this is just an unnecessary expense.
- Continuity: Starting with a scalable app means you will have fewer things to worry about once your business starts growing and be able to concentrate on more important things.
The first step in understanding how to build highly scalable web applications is learning about the prerequisites every such app is expected to have.
As with any digital product, the less complexity is added to the web app, the easier it is to add new features, integrate them with other services, and fix issues. What’s more, simplicity reduces maintenance costs, which makes your app more economically feasible in the long term.
The approach in which the app runs on several interconnected but independent servers, so even if one of them malfunctions, the service remains operational. So, in a sense, decentralization is a fancy way of saying “Don’t put all eggs in one basket.”
A concept closely related to decentralization, loose coupling describes a system in which elements, although connected, are not dependent on each other. The goal here is to eliminate any weak points that, once affected, will crash the entire system, so your app will keep working with little to no loss in functionality.
An important property of a scalable web app architecture is its fine-grained nature. Instead of being a monolithic entity, the app can be decomposed into a set of relatively independent services. Not only will it make the development process easier and more focused, decomposition will also streamline its deployment to different platforms.
The ability to draw additional processing power from unused hardware. With scalable parallelism, the app will utilize available resources more efficiently, eliminating the need to pay for additional servers.
The ability of the app to handle several tasks at the same time instead of waiting for the response to each request. While delays in non-asynchronous applications running on modern hardware are microscopic, with enough users the effect can become noticeable, so take care of it as early as possible.
Unless you are a software engineer, some of these concepts might seem intimidating. So, instead of tackling this task on your own, you can partner with a software development company experienced in building scalable apps and focus on other aspects of running a business while they will deal with the technical details.
The Remote Collaboration Angle
In a sense, working on a scalable software project remotely can entail the same issues as a poorly scaled service. What follows is a list of the challenges our team has experienced in the past, along with suggestions on how to avoid them.
Reliance on Location-Bound Servers
Generally speaking, the development process is susceptible to the same kind of risks as the app itself. So it makes sense to have some of the solutions to these problems also related. For instance, relying on a physical on-premise server might sound reliable – yet it also introduces the risk of losing progress due to its malfunction. What you should do instead is to use cloud-based services, which are decentralized and easy to access remotely.
Lack of Robust Communication
In the same way as a cluttered code makes it difficult to scale a web app, any loosely arranged information is difficult to process. When working with remote developers, some business owners pay little attention to communication channels. As a result, the team does not receive updates on time and the final product deviates from the initial vision. Remote app developers usually have experience with remote communication and project management tools, so a good place to start is to discuss their tools of the trade as early as possible.
Working remotely means handling corporate information online, so you want to make sure none of it ends up in the wrong hands. Fortunately, there are plenty of ways to secure it without going offline, from configuring access rights to setting up a virtual private network that protects corporate processes from external parties. Check with your development team to make sure the chosen tools are suitable for them.
Scalability: Best Practices During the Web App Development
Finally, here are some recommendations on how to scale a web app. Even if you have a web application development company to do the job, you may want to be familiar with these to follow the project more closely and set the expectations right.
Emphasis on Microservices
Scaling an application is easier when you can focus on a specific service without going through the entire codebase. The best way to do this is to use a microservice architecture in which components can be tested, maintained, and upgraded individually, saving time and resources.
No matter how powerful is the cloud your web app runs on, it does have its limitations. Instead of throwing resources at the task, make sure the available ones are used efficiently. For example, caching the web service will reduce the amount of data retrieved per request and offload the original database.
Speaking of performance limitations, knowing the limits of your app is absolutely essential for evaluating its scalability. One way to do it is to set up a scenario that simulates a worst-case scenario of overloading and see how it behaves. Some businesses choose to forego this step because it is time-consuming. Mind, however, that fixing the undetected problems later will be far more taxing, so find where to fit these tests into the development process.
Databases are among the most notorious bottlenecks for the performance of scalable apps. Fortunately, there is a relatively simple way to minimize this effect – using several databases. The market offers numerous options to choose from, and while some of them sound mutually exclusive, they can actually complement each other in tandem. For example, SQL and NoSQL can work miracles when combined, improving reliability and optimizing load balancing.
Depending on the service you are aiming to create, you will need to choose between stateful and stateless protocol. The former works great for apps in which speed and performance are crucial, whereas the latter is indispensable for reducing the server load. In other words, you need to understand which aspect of your app needs to be scaled, and choose accordingly.
In a sense, scalability is a strategic property. Initially, it requires some time and resources to be set up and doesn’t seem to give anything in return. Once your customer base starts growing, it becomes a disputable question of keeping up with the demand versus losing that hard-earned competitive edge. So, when choosing a software development company to bring your vision to life, pay attention to their expertise with scalable web apps to achieve long-term success.