How to Implement CSS in Micro Front-End

web, internet, symbol-1045994.jpg

Micro Frontends have grown in popularity recently as a software design strategy that promotes scalability, modularity, and autonomous development inside frontend applications.

Micro Frontends allow teams to operate independently on different areas of a bigger product by splitting monolithic frontend software into smaller, self-contained parts.

In this article, we’ll look at the concept of Micro Frontends and how CSS fits into this architectural approach.

Understanding Micro Frontends

Micro Frontends bring the principles of microservices to frontend programming. All components of an application in a traditional monolithic frontend architecture are tightly connected, making scaling, deployment, and maintenance difficult.

Micro Frontends address this issue by splitting the frontend into loosely linked, independent modules, each responsible for a specific functionality or feature.

Each Micro Frontend is a separate entity with its dedicated team, technological stack, and development lifecycle.

These modules can be created using a variety of frameworks, languages, and libraries, allowing teams to select the best technology for their individual needs. This strategy encourages flexibility, faster development, and easier maintenance.

The Role of CSS in Micro Frontends

CSS is essential in Micro Frontends because it ensures uniform design, layout, and user experience across multiple modules.

In a micro frontend architecture, CSS may be separated within distinct modules or distributed globally among several modules.

Although each Micro Frontend module might have its own CSS files, a cohesive and unified design system is required to maintain a consistent user interface (UI) and branding throughout the program.

CSS in Micro Frontends can be approached in several ways:

  • Shared CSS Files: One solution is a central CSS file containing shared styles all Micro Frontend modules utilize.

    This file can be incorporated into each module to ensure the application has a uniform appearance and feel.

    This method, however, may result in competing styles and increased connectivity across modules, thereby restricting the autonomous creation and deployment advantages associated with Micro Frontends.

  • Scoped CSS: Scoping CSS within each Micro Frontend module is another technique. This entails enclosing CSS styles within certain component or module borders to prevent styles from leaking or interfering with other modules.

    Scoped CSS is possible with CSS-in-JS libraries, such as styled-components or CSS modules, which allow styles to be locally scoped to a specific component or module.

    This method encourages modularity and lowers the probability of style clashes.

  • Design System and Component Libraries: A design system is a collection of reusable components, patterns, and rules that maintain uniformity across an application or company.

    A shared design system or component library in Micro Frontends aids in the maintenance of a consistent UI and branding.

    CSS styles can be defined in the design system and imported into Micro Frontend modules. This method allows for consistent styling and promotes code reusability.

Some benefits of CSS in Micro Frontends

CSS in Micro Frontends offers several benefits:

  1. Scalability: CSS can assist in managing the expansion of a Micro Frontend architecture. Teams with a well-structured CSS codebase can extend the app’s functionality by introducing or altering modules without affecting overall UI consistency.
  1. Modularity: CSS scoping approaches like CSS or CSS-in-JS libraries make module isolation and encapsulation easier. Every module can have its own CSS styles, which reduces the possibility of style clashes and allows for independent creation and implementation.
  1. Consistency: A shared design system or component library offers a unified user interface across all Micro Frontend components. Teams may establish a cohesive user experience across the application using predefined CSS styles and design concepts.
  1. Reusability: CSS styles defined in a design system or component library can be shared across several Micro Frontend modules. This encourages code reuse, saves duplication, and allows uniform branding and styling.

Programming languages and frameworks using CSS in micro frontends

  • JavaScript with Frontend Frameworks:

React: React is a popular JavaScript library for developing user interfaces. React can be used alongside CSS, including CSS modules or CSS-in-JS libraries, to construct reusable and modular components within Micro Frontend modules.

Angular: Angular is a TypeScript-based framework for building web apps. Angular includes its styling system, allowing developers to use CSS or other styling solutions such as SASS or SCSS to style Its components.

Vue.js: Vue.js is a progressive JavaScript framework that can be used with CSS to develop interactive and scalable user interfaces. Vue.js offers numerous stylistic options, including CSS modules, scoped CSS, or CSS-in-JS libraries like Vue Styled Components.

Backend Languages and Frameworks

  • Node.js: Node.js, a JavaScript runtime environment, can be used on the backend to develop server-side APIs or manage server-side rendering in a Micro Frontend architecture. CSS can be used to style server-rendered components or pages.
  • Python: Python, a versatile programming language, can be utilized with CSS in Micro Frontend systems. Frameworks like Django or Flask can handle backend functionality, while CSS is utilized for frontend styling.
  • Ruby: Ruby is another prominent programming language used in web development. Frameworks like Ruby on Rails or Sinatra can be used with CSS to create Micro Frontend applications.

CSS-in-JS Libraries

  • Styled-components: Styled-components is a popular CSS-in-JS package that allows developers to write CSS styles directly in their JavaScript code. This approach can be used with any JavaScript framework to style Micro Frontend modules.
  • Emotion: Emotion is another CSS-in-JS package that provides a robust and versatile approach to defining and maintaining CSS styles in JavaScript. It can be used with JavaScript frameworks to style Micro Frontend components.

Challenges and Best Practices

While CSS in Micro Frontends has many advantages, it also has certain drawbacks:

  1. CSS Style Conflicts: Because multiple teams work on distinct modules, there could be a chance that CSS styles will clash. Effective communication, defining style norms, and regular team involvement can all help address this issue.
  1. Performance Considerations: Using many CSS files from various Micro Frontend modules can result in larger file sizes and more network calls. CSS minification, code splitting, and bundling are all strategies that can help improve performance.

Best practices to make the most of CSS in Micro Frontends

  • Create a Shared Design System or Component Library: Create a shared design system or component library that provides common styles, UI patterns, and branding requirements. This provides uniformity and makes CSS integration easier among Micro Frontend modules.
  • Use Scoped CSS: To isolate styles within module boundaries, use scoped CSS techniques such as CSS modules or CSS-in-JS libraries. This encourages modularity and lowers the likelihood of stylistic clashes.
  • Communicate and Collaborate: Promote regular communication and collaboration among teams working on various Micro Frontend components. This helps to align CSS styles, resolve conflicts, and keep a consistent user interface.
  • Optimize Performance: Use optimization strategies like code splitting, CSS minification, and bundling to ensure fast CSS file delivery and improve overall application performance.


CSS is crucial in Micro Frontends, enhancing scalability, modularity, and UI consistency. This enables teams to create flexible, maintainable, visually appealing front-end applications by adopting shared design systems and promoting collaboration.

If you find this article thrilling, discover extra thrilling posts like this on Learnhub Blog; we write a lot of tech-related topics from Cloud computing to Frontend Dev, Cybersecurity, AI and Blockchain. Take a look at How to Build Offline Web Applications. 


Leave a Comment

Your email address will not be published. Required fields are marked *