Enhance your Composable Frontend Architecture with Micro-Frontends

Why does your organization need Composable Frontend architecture?

One major reason your organization needs a Composable Frontend architecture is that market needs, technology, and customer preferences keep changing. Staying afloat demands agility, and your application must adjust quickly to these changes and meet new trends and customer expectations.

However, using a traditional monolithic frontend architecture makes this nearly impossible. In a monolithic frontend application, all components are tightly coupled, so changes in one part can require extensive updates throughout the application.

For example, updating the source code containing the UI may require you to alter multiple interconnected sections of your parent application, increasing the risk of bugs and leading to longer development times. Additionally, deploying updates often means redeploying the entire frontend, causing potential downtime.

In contrast, newer architectures, such as the Composable Frontend architecture, prioritize modularity. They break down the UI into reusable components, each handling its own logic and display.

This modular approach allows for independent development and updates of specific components without impacting the entire application. It also supports the use of Micro-Frontend architecture, where small, self-contained applications can be developed, tested, and deployed independently by development teams using different tech stacks.

As a result, independent teams can collaborate more effectively, accelerate time to market, enhance reusability, and gain greater flexibility, ensuring your application can quickly adapt to changes and meet customer expectations.

Where do Micro-Frontends come in?

Now that you understand why you need Composable Frontend architecture, the big question is how you can achieve this using Micro-Frontend architecture.

Micro-frontend architecture refers to the use of modular segments of a web application’s frontend that can be developed, tested, and deployed independently. This architectural style follows an approach similar to the microservices architecture by breaking down complex frontend applications into smaller, independent components.

Based on this definition, Micro-Frontends can be used as the building blocks of your Composable Frontend architecture. The whole process is like putting together a puzzle, where each piece is a tiny part of the whole picture.

Strategies for achieving true composability using Micro-Frontends

There are several ways to achieve a truly composable architecture as an approach to frontend development. These methods fall into three main categories: development approach, orchestration methods and communication. Let’s discuss them in the following paragraphs.

The development approach

Let’s say you’re using a monolithic architecture. Depending on its size, you can split the application into manageable pieces in three primary ways: namely, using a vertical split, a horizontal split, or a mixture of both.

You can use the horizontal split approach when you want to divide your application based on the user interface (UI) elements or pages. For example, each of your Micro-Frontends will be responsible for specific UI elements like your header, sidebar, dashboard, product listing, or checkout.

The vertical split approach involves dividing your monolithic application based on business features, which later become Micro-Frontends, each focusing on a specific feature or user journey. For example, let’s say you have a travel booking application; it could have separate Micro-Frontends for search, booking, payment, and user profiles.

Orchestration methods

Unlike microservices, Micro-Frontends have to come together to form the parent application. There are two ways you can achieve this: client-side orchestration and server-side orchestration.

For client-side orchestration, the browser integrates multiple Micro-Frontends using various technology stacks. Common methods include:

• Iframes: A native browser feature that allows for composition by providing a viewport to render each Micro-Frontend.
• Module Federation: A build-time integration approach to orchestration.
• Specialized frameworks: Such as Micro-Frontend-specific frameworks like micro-Ic and single-spa, which focus on managing and integrating micro-frontends.
• Mia-Platform Microfrontend Composer: This Composer is a user-friendly graphical interface, enabling both experts and beginners to configure Micro-Frontends easily without writing code.

These technology stacks, often based on JavaScript frameworks or libraries, work together to seamlessly integrate Micro-Frontends into a cohesive user experience.

Server-side orchestration, on the other hand, involves using the backend server for seamless integration and rendering of the Micro-Frontends into HTML, which is then sent to the browser. This approach offloads the responsibility of integration from the client and minimizes the amount of JavaScript required on the frontend.

Communication

Now, let’s discuss the final approach: setting up how different parts of your application communicate. This step is crucial in Micro-Frontend architecture setups, ensuring that components work together smoothly and effectively. To achieve this, you can use any of the following methods:

• Browser API: Since all Nicro-Frontends are rendered in the same browser, they can access web browser APIs such as Local Storage, IndexDB and other web storage APIs. This allows data to be stored by one Micro-Frontend and retrieved by others.
• Browser events: The browser’s inherent event system enables communication across individual components. For example, using iframes requires using the window object, window.postMessage, to broadcast events to the parent application, which listens for events from iframes and handles them. Custom Events can also enhance communication between components.
• Global state managers: Tools like Redux enable the sharing of data across application components. Most modern frameworks support such state managers, some of which work seamlessly across different frameworks.
• Web servers API: Unlike browser-based methods, server APIs store data on the server, not in the browser. Servers provide endpoints or WebSocket connections to facilitate communication between Micro-Frontends.

How to overcome challenges of using Micro-Frontends

When you attempt to enhance your composable architecture, you might face some challenges. While using Micro-Frontends makes your system more flexible and scalable, it can be tricky to keep all parts looking consistent and manage their dependencies well.

For instance, your different Micro-Frontend applications may use different versions of the same tools, which can cause conflicts or make things look different than expected.

Let’s look at some of these issues as well as their potential solutions.

Style leakage

Managing CSS (Cascading Style Sheets) can be challenging if it is not properly carried out.
Let’s say you have different teams working on a complex e-commerce website: Team A on the homepage, Team B on product details, etc. Then, styles clash when Team C tries to integrate parts from Teams A and B, leading to a visually inconsistent user experience.

In such situations, you can use CSS modules or Shadow DOM for style encapsulation. CSS modules generate unique class names to limit style leakage, while Shadow DOM isolates styles within a web component, ensuring they don’t interfere with other parts of the application.

Global styles and third-party libraries

When you use styles or third-party style libraries that apply styles globally, you may encounter various issues. These issues appear as clashes or inconsistencies in various parts of the project composed of smaller components.

As a solution, it’s better to stick to styles needed only for specific parts of your project. You can achieve this using methods like CSS-in-JS, which allows you to add styles directly to your JavaScript code. This way, you avoid having too many styles affect everything at once, ensuring consistency and preventing unexpected changes.

Dependency management

Managing dependencies between independent modules is a common challenge.
Smaller components might include redundant CSS files, JavaScript libraries, or dependencies, increasing the application’s size and causing performance issues. To avoid this, you can do two things.

• First, use the same tools across your project. For instance, if one team uses Bootstrap for styling, all teams should use Bootstrap. This consistency makes your project lighter and faster.
• Second, keep everything updated. Ensure everyone uses the latest versions of the tools, as updates often fix bugs and improve compatibility. Set rules for how often to update and which versions to use.