Top-Performing Front End for Your Fintech Solution: 2024 Development Trends

Based on the input from Derkach Vladyslav, Frontend Tech Lead at INSART.

What’s trending in frontend 

Сomponent-based frontend development

“Modular” or “component-based” development is widely used in software frameworks like React and Vue and microservices architectures. From building large-scale applications to organizing code within a single app, component-based development helps ensure high maintainability, scalability, and reusability. Modular design helps deliver optimized apps that are highly competitive in the changing market.

In library development, it offers flexibility and customization options to developers who use the library. That’s a fundamentally new approach to building libraries, which we utilize at INSART. In “modular” or “component-based” development, you download individual components or modules of a library and customize them to suit your specific needs. That is basically the standard approach, but the other way around: developers download the entire library as a single package and include additional code to customize it for their use case if needed. 

With modular development, teams have more granular control over the functionality and appearance of the library, which allows for better flexibility and efficiency in building apps.

React Server Components (RSCs)

React Server Components evolve React from a pure rendering library, gearing it with data-fetching capabilities and remote client-server communication within the framework. To better understand what that means and how exactly things got better now that frontend developers have RSCs, let's take a brief detour to pre-React times.

What web development challenges RSCs solve

Before React, web development had a tight client-server relationship, which ensured easy data fetching but restricted scalability.

Enter React, bringing in composability and incremental adoption, decoupling client-server concerns for more flexible frontend development. This technology took web standards and built them up from multi-page to single-page apps, improving data delivery and interactivity while elevating the developer experience.

In the context of frontend optimization, React developed server-side rendering (SSR) to simplify initial page load.

• + Server-side rendering (SSR) sends pre-rendered HTML to the client and hydrates it with JavaScript, allowing the content to appear on user screens faster. 
• - However, all data and JavaScript must be fetched before any interaction, resulting in delays. 
• + React Suspense tackles this by enabling server-side HTML streaming and selective hydration, prioritizing component rendering and interaction based on user actions.
• - Still, some challenges persist, including the need to fetch all page data ahead of rendering and use client-side JavaScript for component interaction.

React Server Components (RSCs) take improvements a step further by fetching data and rendering on the server only, streaming resulting HTML into the client-side React component tree (if needed, alongside other Server and Client Components). Simply put, this approach boosts performance by eliminating the need for client-side re-rendering. 

At the same time, hydration of Client Components occurs while RSCs stream in, with compute load shared between client and server. The server takes care of compute-intensive rendering and transmits only interactive code to the client. When state changes make an RSC call for re-rendering, it refreshes on the server and seamlessly integrates into the existing DOM without a need for a hard refresh, preserving client state while updating parts of the view from the server.

React’s latest version, React 19, is set to be released pretty soon, around May 2024. From what’s announced, new features will include SEO, “Use Server” (performing tasks or handling operations within a web application using a server-side component or functionality,) “Web Comp” (web components,) “ref Prop” (reference prop in React.js utilized to obtain references to DOM elements or React components,) and “Use Hook” (likely, custom React hooks.)

HTMX

While the hype around HTMX started in 2023, the technology has been on the rise since late 2020ies. Now, more and more development teams are transitioning from client-side rendering to HTMX.

Actually, this JavaScript-based frontend library is not brand new; rather, it is an old HTML concept revisited and wrapped anew. The purpose of HTMX is to ensure dynamic interfaces and high browser interactivity within HTML while eliminating the need for extensive client-side JavaScript code. The app built on HTMX will work even in case JavaScript is disabled or not supported by the browser. The library lets developers enhance traditional server-rendered HTML with dynamic behavior. It also helps achieve flawless client-server communication through HTML attributes.

How HTMX works

1. HTMX gives HTML elements attributes to specify dynamic behavior and interaction (`hx-get,` `hx-post,` `hx-swap,` etc.). Developers use these attributes to define actions such as fetching data from the server, submitting forms, updating UI elements, and handling user interactions.

2. When a user clicks a button or submits a form, interacting this way with an HTMX-enhanced element, HTMX automatically sends an AJAX request to the server using the specified HTTP method (GET or POST) and URL. After processing the request, the server returns the updated HTML content or data.

3. With a server response having checked in, HTMX updates the HTML content of the specific element on the page based on the defined behavior (replaces, appends, or prepends content). This allows for seamless and efficient partial page updates without reloading the entire page.

4. HTMX provides support for client-side events, allowing developers to define JavaScript functions to handle various events triggered by user interactions or server responses. These events can be used to customize behavior, update UI elements, or perform additional client-side logic.

5. HTMX is fine-tuned for progressive enhancement, which differs from SPA-focused React using component-based architecture. HTMX enhances server-rendered HTML with dynamic behavior, but the core functionality remains accessible through traditional HTML forms and links.

HTMX took second place in the 2023 JavaScript Rising Stars “Front-end Frameworks” category, following React. From the growing popularity of the library, it looks like we will see more of it in the next few years. 

By the way, HTMX’s X account, by all means, deserves to be featured here.

How HTMX differs from React

Both technologies let developers create dynamic web applications. However, they are quite different in performance, approach, architecture, and learning curve. To choose between HTMX and React, you need to consider project requirements, the dev team’s expertise, and the desired performance attentively. Your preference for server-side vs. client-side rendering plays a big part here, too. If you're not sure what fits your case the best, you can always clarify that on a quick call with our experts.

Here are the major differences between HTMX and React.

• HTMX sticks to a progressive enhancement approach. It involves adding dynamic behavior to traditional server-rendered HTML using HTML attributes. In contrast, React is a JavaScript library used for single-page applications (SPAs) with a component-based architecture. 
• React primarily focuses on client-side rendering (the Virtual DOM and Reconciliation algorithms help handle UI updates on the client side). With HTMX, it’s a different story: it enhances server-side rendering with dynamic behavior and interactivity, hardly leveraging client-side JavaScript at all.
• HTMX is designed to be lightweight and easy to use, suggesting a minimal learning curve for developers familiar with HTML and server-side programming. React, however, has a steeper learning curve due to its component-based architecture, JSX syntax, and concepts like state management and lifecycle methods.
• React's virtual DOM, coupled with an optimized rendering process, better serves complex SPAs with frequent UI updates. HTMX shows higher performance in apps with sufficient server-rendered HTML. Another use case is adding interactive features to traditional web apps.
  
  

Popular modern frontend architecture types

Over the last ten years, frontend architecture has evolved much, leaving us developers with a variety of options. Let’s zoom in on those new ways to arrange high-level structures that proved effective and find out in which cases they ensure the best results for Fintech companies.

2014: Isomorphic architecture

Due to fast initial page loads and seamless user experience, this type of architecture is an excellent choice for building trading and online banking platforms and financial analytics dashboards. 

Isomorphic web architecture allows for the type of JavaScript app you can run both on the client- and the server-side. After the client loads an HTML uploading the JavaScript app to the browser, the app starts running like a SPA. However, unlike with SPA, the server handles the first render. On the user side, it looks like this: once a user has typed in the web app address, the server starts by completely rendering HTML for search engine crawlers to analyze the web pages (this makes your web apps’ SEO work.) The final result is a SPA web app with an already rendered page and JS bundles.

• + Isomorphic web architecture is responsive and ensures prompt data updates and a multitude of UI/UX options. Loaded server is not a hindrance to quick rendering, as the processed code is transferred to the client.
• + This type of architecture lets users immediately see the content in the browser and provides great routing, linking capabilities, and SEO.
• - A limited tech stack allows you to use only JS frameworks and tools.

2015: Micro frontend

This modular approach employs frontend app decomposition, where it’s split into “micro-apps.” These apps work together, appearing on a single page for the end-user, but each is an independent entity. This way, the team can run development and deployment independently, too. 

• + Micro frontend is highly scalable, which makes it a sensible choice for enterprise customers. You can build huge software parts in parallel, leveraging the help of several teams.
• + High customization potential makes micro frontend an excellent fit for building personal finance management apps.
• + High flexibility and easy integration with existing systems can translate to a seamless payment experience in payment gateways.
• - One big drawback is that this approach can overcomplicate the app and result in code duplication.

2015: Progressive web apps (PWAs) 

A PWA combines the features of a web platform (through the technologies it's built on) and a platform-specific app (similar user experience). Basically, it’s an SPA plus services running in the browser. This approach allows you to pack your web app with offline experiences and ensure background synchronization, all while ensuring app security with HTTPS. 

To the end user, this type of app appears as a pop-up message on the website with a suggestion to add the app to the device’s OS launch screen. Once the user accepts, the app is added.

• + Windows and Android support PWA.
• + Remote updates are available.
• + Easy and secure installation for an end user.
• - The offline functionality of PWA architecture is not available on iOS.
• - Certain browsers (like Firefox) and OS don’t support PWA.
• - PWA is efficient if the business is stable and has established expectations from the app, so it’s not a great option for startups.

2019: Island architecture 

The islands architecture was developed and popularized by Astro, a web framework for content-driven websites. It encourages small, specialized fragments of interactivity within server-rendered web pages through partial (or selective) hydration.

These “islands” produce progressively enhanced HTML, providing this enhancement in a specific manner. There are a number of entry points, in contrast to a single app handling full-page rendering. You can deliver the script for each of these interactivity “islands” independently, and hydrate it in the same way, unlike in JS-based frameworks, leaving the rest of the page static HTML.

• + Islands ensure higher frontend performance by stirring away from monolithic JS patterns and automatically combing the redundant JS out of the page. 
• + Astro islands let developers keep getting the most out of their favorite UI components and frameworks.
• + You can embed SPAs.
• - Compatible with a very limited number of tools.
• - Poor choice for highly interactive apps.
• - Every page change triggers a refresh.

Fintech businesses providing multiple services (payments, banking, analytics, etc.) use islands architecture to enable the autonomous operation of each service and ensure its communication with other parts of the app when needed.

What’s next in frontend development

Right now, our team can’t wait till the May release of React 19 to check out new features. As for further perspective, there’s something we want to share, too.

• Our view is that AI isn’t likely to replace humans in the next few decades. Freeing up resources by automating simple tasks — yes. Wiping out developer jobs — no. AI will make sure more exciting tasks are left for humans, offering its full potential for innovation to those who can leverage it.
• The same applies to no-code and low-code platforms: their wider adoption is an impetus to get to the next level as a professional and a leg-up for achieving more complex and impressive results in frontend development.

As a Startup Studio & Innovation Lab, we keep abreast of the latest trends and hone our development skills using a time-tested tech stack. If you need a tech partner with extensive experience in the financial domain to build cost-efficient, robust, and scalable Fintech solutions, we are ready to help. Let us know what data-rich, cloud-native, and AI/ML-based solutions we can develop to accelerate your startup’s growth.