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In the earlier blog on Runtime microfrontends for scalable frontend architecture, we explored what are runtime microfrontends and how dynamic composition enables independent deployments and faster delivery. The next step is understanding how this works in real systems not as theory, but as an architectural structure teams can design, build, and operate.
In this blog, I’ll explain the core components of runtime microfrontends, how microfrontend runtime integration is achieved using module federation, how routing and authentication are handled, and how shared dependencies are managed safely.
System components in a runtime microfrontend platform
A runtime microfrontend platform is built from clearly defined architectural roles. Each component has a focused responsibility, which helps maintain independence while still enabling integration at runtime.
Core architectural elements of runtime microfrontends
| Component | Responsibility |
|---|---|
| Host Application (Shell) | Handles authentication, layout, top-level routing, and dynamic loading of remotes |
| Remote Microfrontend Apps | Independent frontend applications responsible for specific product or domain features |
| Shared UI Library | Versioned design system and common UI components |
| Shared Utility Modules | Common services such as API clients, feature flags, or telemetry helpers |
| Authentication Service | External service providing identity and access tokens (JWT or OAuth based) |
Business logic lives inside remotes. Platform logic lives in the Host and shared libraries. When those lines blur, teams lose autonomy and runtime failures become harder to isolate - a common anti-pattern in poorly designed runtime microfrontends.
Runtime composition and application orchestration
Runtime microfrontends shift integration from build time into the browser. This requires a controlled orchestration model.
Dynamic loading with module federation in runtime microfrontends
Most production implementations rely on module federation, specifically webpack module federation, or equivalent runtime loaders to enable microfrontend runtime integration directly in the browser. Each remote exposes specific modules, and the Host dynamically imports them when needed.
The flow typically looks like this:
- Host maintains a manifest of remote entry points
- Routes or feature triggers determine which remote to load
- Code is fetched and executed in the user’s browser
- UI mounts into containers provided by the Host
This enables independent deployments without rebuilding the full frontend.
Host responsibilities in module federation-based architectures
In frontend module federation setups, the Host is not where product features live. It functions as a platform layer and is responsible for:
- Authentication and session handling
- Global layout and navigation frame
- Route-based loading of remotes
- Centralized error boundaries and telemetry hooks
Keeping the Host thin prevents webpack module federation architectures from collapsing into a second frontend monolith.
Routing, authentication, and cross app communication in runtime microfrontends
Runtime composition only works when shared concerns are handled centrally and domain logic remains isolated.
Routing strategy
The Host owns top-level routes such as:
/dashboard
/product-a/*
/product-b/*
When a product route is matched, the corresponding remote microfrontend is loaded dynamically. The remote then manages its own internal routing. This pattern keeps global navigation predictable while preserving team autonomy — a core goal of runtime microfrontends.
Authentication and user context in microfrontend runtime integration
Users authenticate through the Host, which manages session tokens and exposes identity context to remotes through shared services or framework context providers.
Remotes consume identity information but do not implement separate login mechanisms. This centralized approach is critical for security and governance in microfrontend runtime integration scenarios.
Shared state and event communication
Some information must cross microfrontend boundaries, such as user preferences or selected tenant context. This is typically handled using:
- Shared state modules
- Lightweight event mechanisms
- Framework context providers
The principle is strict: share only what is required for cross-domain workflows. Everything else remains private to the microfrontend.
Dependency management and operational stability
Runtime loading introduces operational risks that must be managed intentionally.
Managing shared dependencies
To avoid conflicts, core libraries are usually configured as shared singletons inwebpack module federation. Teams follow semantic versioning policies and rely on lock files to ensure reproducible builds.
This allows upgrades to happen independently while preventing incompatible versions from being loaded together in production.
Observability and failure handling in runtime microfrontends
Because failures can occur during remote loading, production systems implement:
- Centralized error capture in the Host
- Remote-level performance monitoring
- Graceful fallback UI when remotes fail to load
Without this, debugging becomes extremely difficult once multiple teams deploy independently using frontend module federation.
Why runtime microfrontends architecture matters at scale
Runtime microfrontends scale well not just because of tools like module federation, but because the architecture matches technical boundaries with team ownership. Each team can build, test, and deploy its own product area independently, while the Host continues to provide navigation, authentication, and platform services. This setup lets features evolve without teams needing to coordinate every release, and it limits failures to a single product area. At the same time, sharing UI components, state, and utilities in a controlled way helps avoid fragmentation and maintains a consistent user experience across the platform.
With good dependency management and strong observability, a runtime microfrontend architecture lets frontend systems grow without creating fragile connections or deployment slowdowns. This helps teams keep delivering quickly, even as products and teams get bigger. For organizations with several frontend teams and fast-changing products, microfrontend runtime integration offers a practical way to scale for the long term, provided they are built with clear architectural goals and not just for tool convenience.
Designing runtime microfrontends that scale requires careful architectural decisions across teams, platforms, and deployments. At Opcito, we help engineering organizations implement production-ready microfrontend platforms built for long-term scalability. To discuss your architecture and next steps, connect with Opcito’s microfrontend experts.
