Silverlight XAML to React: A 10-Step Migration Guide for Architects

Microsoft officially ended support for Silverlight in October 2021, yet thousands of mission-critical enterprise applications—from high-frequency trading platforms to healthcare patient portals—remain trapped in an obsolete plugin architecture. For the enterprise architect, the "Silverlight problem" isn't just about a dead runtime; it is about a $3.6 trillion global technical debt crisis where 67% of legacy systems lack the original documentation required for a standard rewrite.

The traditional path of manual code translation is a death march. According to Replay's analysis, the average enterprise rewrite takes 18 months, and 70% of these projects either fail or significantly exceed their original timelines. The challenge lies in the fundamental paradigm shift from XAML’s imperative, stateful nature to React’s declarative, functional approach.

TL;DR: Migrating from Silverlight to React is no longer a manual "search and replace" effort. This silverlight xaml react 10step guide leverages Visual Reverse Engineering to bypass missing documentation. By using Replay, architects can reduce manual effort from 40 hours per screen to just 4 hours, achieving a 70% time saving through automated component extraction and design system generation.

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The Architectural Gap: XAML vs. React#

Silverlight was built on the Windows Presentation Foundation (WPF) subset, utilizing XAML for UI definition and C# for logic via the MVVM (Model-View-ViewModel) pattern. React, conversely, uses JSX and a virtual DOM. The migration isn't just a syntax change; it’s a re-architecture of how state flows through the application.

Visual Reverse Engineering is the process of capturing the runtime behavior and visual output of a legacy application through video recordings and metadata analysis to automatically generate modern code equivalents.

Comparison: Manual Migration vs. Replay Automation#

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The Silverlight XAML React 10step Migration Framework#

To successfully navigate this transition, architects must move away from "code-first" thinking and toward "workflow-first" modernization. This silverlight xaml react 10step framework provides a technical roadmap for this transition.

Step 1: Inventory and Workflow Mapping#

Before touching a line of code, you must audit the existing Silverlight footprint. Because 67% of legacy systems lack documentation, you cannot rely on old PDF specs. Start by identifying the "Critical Path" workflows.

Industry experts recommend categorizing screens by complexity:

• •Level 1: Static reports and simple forms.
• •Level 2: Interactive grids with complex filtering.
• •Level 3: Real-time data visualization and complex state-dependent dashboards.

Step 2: Visual Reverse Engineering with Replay#

Traditional migration fails because the source XAML is often a "spaghetti" of nested UserControls. Instead of reading the code, record the application in action. Using Replay, you record real user workflows. Replay’s engine analyzes the visual frames and telemetry to understand the UI hierarchy.

This step bypasses the need for the original source code developers, who have likely left the organization years ago. You are capturing the "as-is" state of the application, which is the only source of truth that matters.

Step 3: Extracting the Design System (The Library)#

Silverlight applications often used custom "Styles" and "ControlTemplates" that are difficult to map to CSS. Replay’s Library feature automatically extracts these visual patterns.

Definition: Design System Extraction is the automated identification of recurring UI patterns (buttons, inputs, modals) from a legacy interface to create a standardized React component library.

Instead of writing CSS from scratch, Replay generates a Tailwind or CSS-in-JS theme that mirrors the legacy branding but utilizes modern responsive principles.

Step 4: Mapping MVVM to React Hooks#

The biggest technical hurdle in the silverlight xaml react 10step process is converting

and into React , , and .

XAML (Legacy):

xml
<Button Content="Submit" Command="{Binding SubmitCommand}" 
        IsEnabled="{Binding IsValid}" />

React (Modernized via Replay):

typescript
import React, { useState, useMemo } from 'react';

const SubmitButton: React.FC<{ onSubmit: () => void }> = ({ onSubmit }) => {
  const [isValid, setIsValid] = useState(false);

  // Replay automates the generation of these functional components
  return (
    <button 
      onClick={onSubmit}
      disabled={!isValid}
      className="px-4 py-2 bg-blue-600 text-white disabled:bg-gray-400"
    >
      Submit
    </button>
  );
};

Step 5: Data Grid and Complex Control Conversion#

Silverlight’s

was incredibly powerful, often handling thousands of rows with complex grouping. Replay identifies these complex structures and maps them to modern React equivalents like TanStack Table or AG Grid. This ensures that the high-density information display required by enterprise users is preserved.

Step 6: API Layer Abstraction#

Most Silverlight apps communicate via WCF (Windows Communication Foundation) or SOAP. Modern React apps require REST or GraphQL.

• •The Strategy: Create a "BFF" (Backend for Frontend) layer.
• •The Implementation: Wrap legacy SOAP services in a Node.js or .NET 8 Web API that serves JSON to your new React frontend.

Step 7: Implementing the "Flows" Architecture#

In Replay, Flows allow you to visualize the entire application architecture. During this step of the silverlight xaml react 10step process, you map the recorded video segments to specific React routes (using React Router or Next.js). This ensures that the user's mental model of the application remains intact, reducing retraining costs.

For more on this, see Modernizing Legacy UI Workflows.

Step 8: Security and Compliance Hardening#

Silverlight relied on the browser plugin for security, which is now a massive vulnerability. Your React replacement must be built for regulated environments.

• •Ensure the new stack is SOC2 and HIPAA-ready.
• •Implement OpenID Connect (OIDC) or SAML for authentication.
• •Replay offers On-Premise deployment options for organizations in highly sensitive sectors like Defense or Banking.

Step 9: Automated Component Refinement#

Once Replay has generated the initial React components, use the Blueprints editor to refine the code. This is where you inject business logic that couldn't be captured visually.

According to Replay's analysis, the AI-assisted refinement process is 10x faster than manual coding.

typescript
// Refined Blueprint Output
interface GridProps {
  data: TransactionRecord[];
  onRowClick: (id: string) => void;
}

export const TransactionGrid: React.FC<GridProps> = ({ data, onRowClick }) => {
  return (
    <div className="overflow-x-auto border rounded-lg">
      <table className="min-w-full divide-y divide-gray-200">
        <thead className="bg-gray-50">
          <tr>
            <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase">ID</th>
            <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase">Amount</th>
          </tr>
        </thead>
        <tbody className="bg-white divide-y divide-gray-200">
          {data.map((row) => (
            <tr key={row.id} onClick={() => onRowClick(row.id)} className="cursor-pointer hover:bg-gray-50">
              <td className="px-6 py-4 whitespace-nowrap">{row.id}</td>
              <td className="px-6 py-4 whitespace-nowrap">${row.amount}</td>
            </tr>
          ))}
        </tbody>
      </table>
    </div>
  );
};

Step 10: Validation and Parallel Running#

The final step in the silverlight xaml react 10step journey is validation. Because you have the original Replay recordings, you can perform "Visual Regression Testing." Compare the new React screens side-by-side with the original Silverlight recordings to ensure 100% visual and functional parity.

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Overcoming the "Documentation Debt"#

The biggest lie in enterprise software is that the source code is the documentation. In reality, the code often contains "dead" paths, experimental features never used, and workarounds for 2012-era browser bugs.

Replay treats the user experience as the specification. By recording the workflows, you are documenting the business intent, not just the technical implementation. This is critical when migrating from Silverlight, as many XAML features (like

) have no direct 1-to-1 code equivalent in React but have clear visual equivalents.

The Cost of Delay#

Every month a Silverlight application remains in production, the risk of a "Zero-Day" exploit in the legacy runtime increases. Furthermore, finding developers willing to maintain C#/XAML Silverlight code is becoming nearly impossible. The talent pool has shifted entirely to TypeScript and React.

By following the silverlight xaml react 10step approach, you aren't just changing a tech stack; you are future-proofing your human capital.

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Frequently Asked Questions#

Can we migrate Silverlight to React if we lost the original source code?#

Yes. This is the primary advantage of using Replay. By utilizing Visual Reverse Engineering, Replay analyzes the application's runtime behavior and UI output to generate React components and documented workflows, making the original source code secondary to the migration process.

How does Replay handle complex Silverlight DataGrids?#

Replay’s AI Automation Suite identifies the structure of complex tabular data and interactive elements. It then maps these to modern, accessible React components using libraries like TanStack Table, preserving the sorting, filtering, and grouping logic inherent in the original UI.

Is the code generated by Replay maintainable?#

Absolutely. Unlike "black-box" transpilers of the past, Replay generates clean, human-readable TypeScript and React code that follows modern best practices. The output includes a documented Design System (Library) and clear architectural flows, ensuring your internal team can take full ownership of the codebase.

What about Silverlight WCF services?#

While Replay focuses on the frontend modernization, the silverlight xaml react 10step guide recommends an abstraction layer. You can continue to call legacy WCF services through a proxy or use Replay’s documentation of data shapes to accelerate the creation of a modern RESTful API.

How long does a typical Silverlight to React migration take with Replay?#

While a manual rewrite of a 100-screen application might take 18–24 months, Replay typically reduces this to weeks or a few months. Most organizations see an average of 70% time savings, moving from 40 hours per screen to approximately 4 hours.

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Conclusion: The Architect's Mandate#

The migration from Silverlight XAML to React is an inevitability, not an option. The risk of maintaining legacy plugins in a modern security environment is a liability no enterprise can afford. By adopting a silverlight xaml react 10step strategy centered on Visual Reverse Engineering, you transform a high-risk rewrite into a predictable, automated evolution.

Don't let your legacy systems become the anchor that stalls your digital transformation. Leverage the power of Replay to turn your recordings into a modern, scalable React future.

Ready to modernize without rewriting? Book a pilot with Replay