Creating Seamless User Experiences: A Comprehensive Guide to Micro Frontend Architectural Patterns
The must-know patterns if you’re looking to start building micro frontends
Micro frontends are a relatively new architectural pattern that has gained popularity in recent years. It involves breaking down a large web application into smaller, independent front-end applications, each responsible for a specific part of the UI. Micro frontends can offer many benefits, such as improved scalability, faster development times, and better resource management. However, building a micro frontend architecture can be challenging, and choosing the right architectural pattern is crucial for success.
In this article, we will explore some of the best patterns for building micro frontends, so let’s get down to it, shall we?
Component Library
This one is probably the most known pattern, and while it might sound simple, the value it adds definitely makes it a great one.
Creating a shared library of components that can be used across multiple micro frontends is an essential part of building a micro frontend architecture. This approach ensures consistency in design, functionality, and user experience and reduces duplicated effort.
For example, you might create a library of components for buttons, forms, navigation menus, and other UI elements that can be used across multiple applications. This approach saves developers time and effort, after all, they don’t have to go and create them themselves from scratch.
What’s even better, using a component library enables teams to work more efficiently and at a faster pace. After all, the design and implementation of each component are consistent, and developers can work on different micro frontends with less friction, resulting in a more productive team.
This is exactly the approach that tools such as Bit enable. By adopting a composable, modularity-first design for your components, and independently storing, testing, and documenting atomic units of UI instead of entire apps at once, your app scales better, and is infinitely more maintainable. This guide will show you how.
💡 Also, check out this video for building Micro frontends in React:
Route-Based Micro Frontends
Route-based micro frontends rely on routing to determine which micro frontend is responsible for handling which URL, and delegates the rendering of content to the appropriate micro frontend. This approach allows different teams to work on different parts of the application, and developers can focus on their areas of expertise.
Of course, this means exactly what you’re thinking, these are all individual applications, which means they have separate servers and potentially, different databases.
In the end, I’m a strong believer that practicality should always trump theory, so take the above statement with a grain of salt and contextualize it within your reality.
For example, if you have an e-commerce site, the product listing and checkout process could be separate micro frontends. When a user navigates to the product listing page, the micro frontend that is responsible for displaying the product listings is loaded, and when the user clicks the “add to cart” button and is redirected to the checkout page, the checkout micro frontend is loaded.
This approach helps ensure that each micro frontend is lightweight, efficient, and easy to manage, allowing teams to focus on specific tasks.
💡 This is once again where Bit can help. Bit lets you easily share and manage reusable UI components across different micro frontends, making it easier to maintain consistency and improve development efficiency. Find out more here.
Let’s be honest, it might sound strange and it might require some reverse proxy magic from your friendly DevOps, but it’s definitely a nice way to keep codebases separate.
Event-Driven Micro Frontends
Event-driven micro frontends use a shared event bus to coordinate communication between micro frontends and trigger events to notify other micro frontends of updates or changes. This approach ensures that each micro frontend can communicate with the other, which is essential for building a cohesive web application.
Think of this pattern as one you can implement and use with pretty much any other architectural pattern listed here. After all, micro frontends are independent applications, they need a way to talk to each other if you expect them to share information.
Granted, you could share the database, and have them all pull data from the same source, but that would make it very inefficient. This alternative however, makes them very reactive and efficient.
Still struggling to understand this one? Think of the following example: if a user adds a product to their shopping cart, an event is triggered that notifies the checkout micro frontend to update the cart summary. The checkout micro frontend can then use this information to calculate shipping costs and tax information.
This approach ensures that each micro frontend is responsible for its specific task and reduces chances for coupling.
Iframe-Based Micro Frontends
If you’re trying to integrate micro frontends built with different technologies into the same app (like having some of them written with React, others with Vue and a few with Svelte), then this pattern can save you a lot of headaches.
Iframe-based micro frontends involve embedding micro frontends in separate iframes, which can be loaded and rendered independently of each other. This approach provides isolation and reduces the risk of conflicts between micro frontends.
You could say that Iframe-based micro frontends are useful for building web applications that require a high degree of modularity and independence.
Heck, given how independent they are from each other, you could potentially use different UI frameworks for each one and the user would be none the wiser.
If you’re doing this, Bit can help by providing “universal” components that can be directly used on any React-based meta framework (like Next and Remix) without having to change any code. Here is a handy tutorial showing you how that works.
The problem with this approach though, is that sharing data between iframes is not a trivial task. For architectures like this one, a great complement is the event-based communication, since it can use an external event bus that is not affected by the iframes.
Server-Side Composition
One potential problem with micro frontends when loaded dynamically in front of the user, is that this person can end up witnessing the loading steps for the website.
Think of a single page that integrates multiple micro frontends, they might load gradually due to a poor internet connection, and when that happens the user experience goes down the drain.
Server-side composition, however, is here to solve this problem. It involves using server-side rendering to assemble the HTML and components of multiple micro frontends into a single page. This approach reduces the complexity of client-side code and provides better control over the page layout and structure.
For example, if a user navigates to a page with multiple micro frontends, the server can render the HTML and components of each micro frontend and assemble them into a single page that is delivered to the user’s browser. This approach ensures that the user sees a fully rendered page immediately, rather than waiting for each micro frontend to load separately.
Did you like what you read? Consider subscribing to my FREE newsletter where I share my 2 decades’ worth of wisdom in the IT industry with everyone. Join “The Rambling of an old developer” !
Client-Side Composition
On the other side of the spectrum, you can also have very complex web apps that use tons of micro frontends. In such a scenario, going with a server-side rendered approach might take too long and hurt the UX as well.
An alternative approach, is to use client-side composition.
Client-side composition involves using client-side scripting to assemble the HTML and components of multiple micro frontends into a single page. This approach can provide a seamless user experience and can improve performance by loading micro frontends as needed (if done intelligently, and especially, preemptively).
For instance, when a user navigates to a page with multiple micro frontends, the client-side scripting can present a pre-loaded, not fully interactable UI and load each micro frontend as needed, based on the user’s interactions.
This approach ensures that the user sees a seamless, dynamic page that responds to their actions, without the need to refresh the entire page. Additionally, client-side composition can improve performance, as micro frontends can be loaded and rendered on-demand, reducing the amount of data that needs to be transferred between the server and the client the first time around.
If you have no idea how to start building your micro frontends, you can check out Bit. It allows you to quickly build, share and reuse components, all while improving the developer experience and their performance. This article shows you how you can easily build micro frontends using Bit.
Conclusion
Micro frontends are great, they offer a big range of benefits, including improved scalability, faster development times, and better resource management. However, building a micro frontend architecture can be challenging, and choosing the right architectural pattern is crucial for success.
Each of the patterns described here offers unique advantages and disadvantages, depending on the project’s specific requirements. Some of them are meant to help you organize the work, and others are there to solve communication problems.
Therefore, it is essential to consider the project’s specific requirements and constraints and choose the pattern that best meets your project’s goals.
Which one is your favorite? And if you consider that I’ve left something out, please leave a note in the comments, I’d love to know what patterns you’re using!
Build Microfrontends with reusable components
Bit’s open-source tool help 250,000+ devs to build apps with components.
Turn any UI, feature, or page into a reusable component — and share it across your applications. It’s easier to collaborate and build faster.
Split apps into components to make app development easier, and enjoy the best experience for the workflows you want:
