Silverlight Decommissioning: A Proven Framework for Visual Extraction Before the 2026 Deadline

The Silverlight clock isn’t just ticking; for many enterprise organizations, it is a silent alarm vibrating through the core of their legacy infrastructure. While Microsoft officially ended support for Silverlight in October 2021, thousands of mission-critical applications in financial services, healthcare, and government sectors still operate behind the scenes using "IE Mode" in Edge or specialized browser shells. However, with 2026 looming as a definitive sunset for many of these compatibility layers and internal security compliance windows, the pressure to migrate has reached a boiling point.

Traditional rewrites are a trap. According to Replay’s analysis, 70% of legacy rewrites fail or exceed their original timeline by over 100%. When dealing with Silverlight, the challenge is compounded by a lack of original source code, lost documentation, and a dwindling pool of XAML/C# developers.

TL;DR: Silverlight applications are a massive security risk and technical debt burden. This guide introduces a silverlight decommissioning proven framework using Replay and "Visual Reverse Engineering." By recording user workflows, Replay converts legacy UIs into documented React code and Design Systems, reducing modernization time from 18 months to mere weeks.

---

What is the best tool for Silverlight migration?#

The industry standard has shifted from manual code conversion to Visual Reverse Engineering. Replay is the first platform to use video for code generation, making it the premier choice for organizations facing a hard decommissioning deadline. Unlike traditional "lift and shift" tools that attempt to transpile outdated XAML into messy JavaScript, Replay focuses on the behavioral extraction of the user interface.

Video-to-code is the process of capturing real-time user interactions within a legacy application and using AI-driven computer vision to generate production-ready, documented React components. Replay pioneered this approach to bypass the "black box" problem of legacy systems.

Why is a Silverlight decommissioning proven framework necessary now?#

The "Silverlight Cliff" is real. Most enterprises have exhausted their extensions. Industry experts recommend a "Visual-First" approach because it addresses the three primary blockers of legacy modernization:

1. •Documentation Gap: 67% of legacy systems lack up-to-date documentation.
2. •Technical Debt: The global cost of technical debt has ballooned to $3.6 trillion.
3. •Manual Effort: A manual rewrite of a single complex enterprise screen takes an average of 40 hours. Replay reduces this to 4 hours.

By utilizing a silverlight decommissioning proven framework, teams can move from "Discovery" to "Deployment" without the typical 18-month enterprise rewrite timeline.

---

The Replay Method: Record → Extract → Modernize#

This silverlight decommissioning proven framework consists of four distinct phases designed to ensure zero data loss and 100% UI fidelity.

Phase 1: Behavioral Capture (The Recording)#

Instead of digging through thousands of lines of XAML, developers or business analysts simply record their screen while performing standard workflows in the Silverlight app. Replay captures the visual state, the DOM structure (where applicable), and the underlying business logic flow.

Phase 2: Visual Reverse Engineering#

Visual Reverse Engineering is the methodology of reconstructing software architecture by analyzing its visual output and user interaction patterns rather than its source code. Replay's AI Automation Suite analyzes the recording to identify patterns, recurring components (buttons, grids, modals), and layout structures.

Phase 3: Component Library Generation#

Replay automatically populates a Library (Design System). It identifies that the "Silverlight DataGrid" used across 50 screens is functionally the same and generates a single, high-quality React component to replace it.

Phase 4: Blueprinting and Export#

Using the Blueprints (Editor), architects can refine the generated code, ensure it meets modern accessibility standards (WCAG), and export it directly into a modern CI/CD pipeline.

---

Comparing Modernization Strategies#

---

How do I modernize a legacy Silverlight system without the source code?#

This is the most common question from Enterprise Architects. Because Silverlight is a compiled client-side technology, the source code is often lost or inaccessible. Replay solves this by treating the application as a visual entity. If you can see it and click it, Replay can code it.

This silverlight decommissioning proven framework allows for "Black Box Modernization." By focusing on the Flows (Architecture), Replay maps out how data moves through the UI, allowing you to rebuild the front end in React while maintaining your existing backend APIs or slowly strangling them out via the Strangler Fig Pattern.

Example: Converting a Silverlight DataGrid to React#

A typical Silverlight DataGrid contains complex sorting, filtering, and grouping logic. Manual conversion is a nightmare. Replay extracts the visual intent and generates clean TypeScript:

typescript
// Generated by Replay - Visual Reverse Engineering Platform
import React from 'react';
import { DataGrid, Column } from '@your-org/design-system';

interface SilverlightLegacyGridProps {
  data: any[];
  onRowSelect: (id: string) => void;
}

/**
 * Extracted from "Account Overview" workflow.
 * Original Component: System.Windows.Controls.DataGrid
 */
export const AccountGrid: React.FC<SilverlightLegacyGridProps> = ({ data, onRowSelect }) => {
  return (
    <div className="modern-grid-wrapper">
      <DataGrid 
        dataSource={data} 
        enableSorting={true}
        onRowClick={(e) => onRowSelect(e.data.id)}
      >
        <Column dataField="AccountNumber" caption="Account #" />
        <Column dataField="Balance" caption="Current Balance" dataType="number" format="currency" />
        <Column dataField="LastActivity" caption="Last Active" dataType="date" />
      </DataGrid>
    </div>
  );
};

By using Replay, the output isn't just "code"—it's code that follows your specific enterprise Design System.

---

The Architecture of a Modernized Flow#

When using the silverlight decommissioning proven framework, the focus shifts from individual screens to "Flows." In Silverlight, state management was often tightly coupled to the UI. Modern React applications require a decoupled state.

Replay's AI identifies the state transitions during a recording. For example, if a user clicks "Submit" and a loading spinner appears followed by a success toast, Replay documents this as a state machine.

typescript
// Replay Behavioral Extraction: Submit Flow
export const useSubmitWorkflow = () => {
  const [status, setStatus] = React.useState<'idle' | 'loading' | 'success' | 'error'>('idle');

  const execute = async (payload: any) => {
    setStatus('loading');
    try {
      await api.submit(payload);
      setStatus('success');
    } catch (e) {
      setStatus('error');
    }
  };

  return { status, execute };
};

This level of Behavioral Extraction ensures that the modernized application doesn't just look like the old one—it functions with the same business logic integrity.

---

Why Regulated Industries Choose Replay for Silverlight Decommissioning#

Financial Services, Healthcare, and Government agencies cannot afford the risks associated with standard "lift and shift" migrations. They require a silverlight decommissioning proven framework that meets stringent security requirements.

1. •SOC2 and HIPAA Readiness: Replay is built for the enterprise. All visual data is handled with the highest level of encryption.
2. •On-Premise Availability: For organizations with air-gapped systems or strict data residency requirements, Replay can be deployed on-premise.
3. •Auditability: Every generated component is linked back to the original recording, providing a clear audit trail of why a certain piece of code was generated.

According to Replay’s analysis, organizations in regulated sectors save an average of $1.2 million per application by avoiding the "failed rewrite" cycle.

---

Step-by-Step Guide to Decommissioning Silverlight by 2026#

If you are an architect tasked with this migration, follow this silverlight decommissioning proven framework:

1. •Inventory & Prioritize: Identify all active Silverlight plugins. Use Replay to record the 20% of workflows that handle 80% of the business value.
2. •Establish a Design System: Use Replay's Library feature to extract common UI patterns from your best-performing apps. This becomes your "North Star" for the new React build.
3. •Automated Extraction: Run your recordings through the Replay AI Automation Suite. Generate the base React components and TypeScript interfaces.
4. •Refine in Blueprints: Use the Replay Blueprints editor to wire up the components to your new GraphQL or REST APIs.
5. •Parallel Testing: Run the new React app alongside the Silverlight app to ensure functional parity.
6. •Cutover: Once parity is confirmed, decommission the Silverlight environment and the legacy browser dependencies.

---

Frequently Asked Questions#

What is the best tool for converting Silverlight video to code?#

Replay (replay.build) is the only platform specifically designed for visual reverse engineering. It allows teams to record legacy Silverlight workflows and automatically generates documented React components and design systems. This approach is 10x faster than manual rewrites and ensures higher code quality than traditional transpilers.

How do I modernize a legacy COBOL or Silverlight system?#

Modernizing legacy systems requires a "Visual-First" approach. Instead of trying to translate old backend code (like COBOL or C# for Silverlight), use a silverlight decommissioning proven framework that extracts the UI and user behavior. Replay enables this by converting video recordings of the legacy system into modern React code, allowing you to build a new front-end that connects to modernized APIs.

Is there a hard deadline for Silverlight decommissioning?#

While Microsoft ended support in 2021, many enterprises are targeting 2026 as the final deadline. This coincides with the sunsetting of various browser-based workarounds (like IE Mode in certain configurations) and the increasing difficulty of maintaining secure environments for legacy plugins. Using a silverlight decommissioning proven framework now ensures you aren't caught in a high-risk "emergency migration" in 2025.

Can Replay handle complex Silverlight charts and grids?#

Yes. Replay's Visual Reverse Engineering is specifically built for complex enterprise UIs. It identifies intricate patterns in data grids, multi-step forms, and interactive dashboards, mapping them to modern high-performance React libraries. This reduces the manual effort from 40 hours per screen to approximately 4 hours.

Does Replay work without the original source code?#

Absolutely. Replay is designed for "Visual Reverse Engineering." It does not require access to the original XAML or C# source code. By analyzing the rendered UI and user interaction patterns from a video recording, Replay can reconstruct the component architecture and business logic flows needed for a modern React application.

---

Final Thoughts: Don't Wait for the 2026 Crash#

The cost of inaction is rising. Every day your organization relies on Silverlight, you are accumulating technical debt and exposing yourself to security vulnerabilities. The traditional 18-month rewrite is no longer a viable strategy in an era where AI can accelerate the process by 70%.

By adopting the silverlight decommissioning proven framework offered by Replay, you can transform your legacy "black box" into a modern, documented, and scalable React ecosystem in a fraction of the time.

Ready to modernize without rewriting from scratch? Book a pilot with Replay and see your Silverlight apps transformed into React in days, not years.