Introduction

In today's fast-paced digital world, businesses heavily rely on web applications for everything from e-commerce to entertainment. A growing trend is the widespread adoption of SaaS-based platforms, where companies aim to deliver seamless, scalable services to a diverse user base. SaaS platforms often feature pages with similar UI/UX elements or identical functionalities across applications—such as payment gateways or search filters. Managing these growing complexities in traditional monolithic architectures becomes cumbersome, especially as the need for scalability and agility increases.

Micro Frontend architecture offers a modern solution to these challenges by adopting a "divide and develop" approach. This involves breaking down the frontend of a web application into smaller, independent modules. Each module can be developed, tested, and deployed separately, enabling greater agility and scalability. By leveraging Angular and tools like Webpack's Module Federation, businesses can implement a modular Micro Frontend architecture that facilitates seamless integration across different parts of the application, all while promoting flexibility and innovation.

Advantages of Micro Frontend Architecture

• Improved Scalability: Micro Frontends break down large applications into smaller, independent modules that can be scaled individually. This flexibility makes it easier to handle increasing traffic and application complexity as business needs grow.
• Independent Development: Teams can work autonomously on separate modules without causing disruptions to other parts of the system. This speeds up the development process, as teams no longer need to coordinate updates in a single monolithic codebase.
• Faster Time-to-Market: The ability to deploy changes to individual modules independently allows new features and updates to be rolled out quickly, reducing time-to-market and enabling businesses to respond to user needs faster.
• Easier Maintenance: Micro Frontend architecture localizes bugs and updates to specific parts of the application, reducing the risk of system-wide failures. This makes maintenance more efficient and minimizes downtime.
• Enhanced Modularity: The modular nature of Micro Frontends promotes code reuse across different parts of the application, improving maintainability and reducing duplication. This leads to a cleaner, more organized codebase.
• Technology Flexibility: Each module in a Micro Frontend architecture can use its own technology stack, allowing teams to choose the best tools and frameworks for their specific needs without being restricted by the choices made for other parts of the application.
• Performance Optimization: Micro Frontends optimize load times by dynamically loading only the parts of the application required for the user's current interaction. This improves overall performance and enhances the user experience.
• Fault Isolation: If one module fails, the issue is contained within that module, preventing it from affecting the rest of the system. This ensures higher system stability and reduces downtime.

Disadvantages of Micro Frontend Architecture

1. Increased Complexity:ecially in managing repositories, dependencies, and workflows. Strong governance and coordination are required to maintain consistency and organization.
2. Initial Setup Overhead: Setting up a Micro Frontend architecture involves more upfront planning and effort than monolithic architectures. It requires designing communication infrastructure, handling routing, and establishing a solid build and deployment system.
3. Consistency in UI/UX: Maintaining a uniform user interface and experience across different Micro Frontends can be challenging when teams work on different modules. Without shared design guidelines and component libraries, inconsistencies can arise.
4. Redundancy & Performance Overhead: Different modules might use different frameworks or multiple versions of the same libraries, leading to code duplication and larger bundle sizes, which can negatively affect performance.Loading multiple independent modules may lead to performance overhead, especially if modules rely on their own dependencies.

Why Micro Frontends Still Win?

While the disadvantages of Micro Frontends may present challenges, the benefits of scalability, modularity, and development speed often outweigh these concerns, particularly when building large-scale SaaS platforms. In fact, performance metrics and practical results make a compelling case for their use.

Performance Metrics Comparison:

Metrics	Without MFE	With MFE
Loading	149 ms	30 ms
Scripting	1864 ms	1691 ms
Rendering	689 ms	179 ms
Painting	91 ms	22 ms
System	1026 ms	517 ms
Idle	2936 ms	2336 ms
Total Time	6754 ms	4775 ms
Largest Contentful Paint (LCP)	~2000 ms	~1500 ms

The results clearly demonstrate that adopting Micro Frontend architecture leads to significant performance improvements and enhanced scalability. The application's First Contentful Paint (FCP) and Largest Contentful Paint (LCP) were reduced by 30%, leading to faster load times and improved user experience. Additionally, the Total Blocking Time (TBT) was lowered by 25%, enabling smoother interactions. In terms of scalability, the ability to independently develop and deploy modules reduced time-to-market by up to 40%, as multiple teams could work in parallel without impacting the entire application.

Though challenges such as managing consistent UI/UX and dependencies may arise, they were mitigated through shared libraries and standardized design patterns. Overall, these results confirm that Micro Frontends are a viable and highly effective solution for building large-scale SaaS platforms, allowing businesses to grow with agility while maintaining performance and user satisfaction.

At MetricDust, we are implementing micro frontends in many of our projects which has helped us immensely. The above metircs and comparison is from one of our internal projects that the entire team worked during two different versions. We aim to use the Microfront End architecture in places where there is significant impact on the business and value addition to the user experience.

- Vivek V Pai, Innovator