When to use a Micro Frontend Architecture?

Micro Frontends is an architectural style for building web apps by decomposing the UI into smaller, self-contained, and independently deployable modules.

Traditionally, web applications are built as monoliths, where the entire frontend is tightly coupled and developed as a single bundle. This can lead to challenges such as difficulty in scaling development teams, slower release cycles, and potential conflicts when multiple teams work on the same code base.

What are Micro Frontends?

Micro Frontends is an architectural style for building web applications by decomposing the user interface (UI) into smaller, self-contained, and independently deployable modules. Just as microservices divide back-end functionality into single responsibility services, micro frontends aim to achieve similar modularity for the frontend.

Micro Frontend principles

Micro Frontends advocate the following principles:

Decomposition

Break the UI into smaller parts, often aligned with functional or feature boundaries. Each part can be developed, tested, and deployed independently. See the subtle art of decoupling systems.

Isolation

Each micro frontend is isolated from the others, usually running in its own runtime or sandbox. This isolation helps prevent conflicts between different parts of the UI and enables using different technologies or versions for different sections.

Independent Deployment

Micro frontends can be deployed separately from one another. This allows for faster release cycles and the ability to update or fix specific parts of the application without affecting the entire UI.

Team Autonomy

Different teams can work on different micro frontends simultaneously. This enhances team autonomy and enables smaller teams to work more independently, making development more scalable. See the section about team autonomy.

Technology Agnostic

Each micro frontend can be built using different technologies (e.g., React, Vue, Angular, etc.) based on what’s best suited for that particular part of the UI.

Consistent UX

While micro frontends allow for technology diversity, efforts should be made to ensure a consistent user experience across different parts of the application.

Routing and Composition

A common challenge with micro frontends is routing and composition—how to combine different micro frontends to form a cohesive user experience. Various strategies and tools are used for handling this, such as client-side routing, server-side routing, and edge-side composition.

Micro Frontends disadvantages

Micro Frontends come with certain disadvantages and challenges that need to be carefully considered before adopting this architectural approach:

Complexity

Micro Frontends introduce additional complexity to the development process. Coordinating communication between different micro frontends, managing shared state, and handling cross-cutting concerns like styling and theming can be challenging.

Increased Network Requests

Having multiple micro frontends might result in more network requests, potentially impacting the overall performance of the application. This can be mitigated using techniques like lazy loading and efficient caching strategies.

Overhead

Each micro frontend typically requires its own runtime and dependencies. This can lead to increased memory usage and slower initial load times due to multiple JavaScript bundles needing to be downloaded.

Integration and Routing

Integrating different micro frontends to create a cohesive user experience can be complex, especially when dealing with routing and navigation. Careful planning and implementation are needed to avoid issues like broken links or inconsistent navigation.

Shared State and Communication

Managing shared state and communication between micro frontends can be challenging. Without proper strategies in place, you might face issues related to data consistency, synchronization, and security.

Testing and Debugging

Testing and debugging become more complex when dealing with multiple independent micro frontends. Ensuring that each micro frontend functions correctly on its own and in collaboration with others requires additional effort.

Versioning and Compatibility

Micro frontends might use different technologies, frameworks, and versions. Ensuring compatibility and managing version updates can become intricate, potentially leading to conflicts and integration challenges.

Tooling and Infrastructure

Setting up proper tooling and infrastructure to support micro frontends can be time-consuming and require expertise. This includes building pipelines, deployment strategies, and monitoring solutions.

Learning Curve

Adapting to the micro frontend approach might require a learning curve for developers who are not familiar with the concept. New team members might need time to understand the architecture and the specific practices involved.

Security Concerns

Isolation between micro frontends is crucial, but maintaining proper security boundaries and preventing data leakage between different parts of the application can be complex.

Increased Initial Setup Time

Compared to a monolithic architecture, setting up the initial structure and communication mechanisms for micro frontends can take more time and effort.

Vendor Lock-in

Some approaches and tools used for micro frontends might result in vendor lock-in, making it difficult to switch to different technologies or architectures in the future.

Conclusion

In summary, while Micro Frontends can address certain challenges in frontend development, they also introduce their own set of challenges and considerations. It’s important to carefully assess the specific needs of your project, the expertise of your development team, and the trade-offs between modularity and complexity before deciding to adopt this architectural approach.