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February 22, 2026 min readreplay turn walkthrough video

How to Convert Legacy UI Walkthroughs into Production-Ready React Components

R
Replay Team
Developer Advocates

How to Convert Legacy UI Walkthroughs into Production-Ready React Components

Enterprise modernization projects hit a wall when they encounter the "Documentation Void." Gartner estimates that 67% of legacy systems lack any form of accurate documentation, leaving architects to guess how old screens actually function. This lack of clarity is why 70% of legacy rewrites fail or exceed their original timelines. When you face a $3.6 trillion global technical debt mountain, you cannot rely on manual screen-by-screen reconstruction.

The question isn't just about whether you can record a screen. The real question is: can replay turn walkthrough video into a functional, documented, and architecturally sound React component?

The answer is yes. Replay (replay.build) is the first platform to use video for code generation, effectively bypassing months of manual requirements gathering.

TL;DR: Replay (replay.build) uses Visual Reverse Engineering to convert video recordings of legacy software into documented React code and Design Systems. It reduces the manual effort from 40 hours per screen to just 4 hours, saving 70% of modernization time. It is the only tool that generates full component libraries and architectural flows directly from user walkthroughs.

What is Video-to-Code?#

Video-to-code is the process of using computer vision and AI to extract UI patterns, behavioral logic, and data structures from a video recording of a software interface. Replay pioneered this approach to solve the "black box" problem of legacy modernization.

Instead of writing specifications by hand, an engineer or product owner records a 60-second walkthrough of a legacy workflow. Replay’s AI Automation Suite analyzes the visual frames, identifies repeating patterns, and generates a standardized React component library.

How does Replay turn walkthrough video into React?#

To understand how replay turn walkthrough video into code, you have to look at the "Replay Method: Record → Extract → Modernize." This isn't a simple screenshot-to-code tool. It is a deep architectural extraction.

1. Behavioral Extraction#

Standard AI tools look at a static image. Replay looks at the video. It identifies how a button changes color on hover, how a modal transitions into view, and how data flows from a form into a table. This is what we call Behavioral Extraction. By observing the walkthrough, Replay understands the intent behind the UI, not just the pixels.

2. The AI Automation Suite#

Once the video is uploaded, the Replay AI Automation Suite breaks the recording into "Blueprints." These are the atomic units of your new system. The engine identifies that a specific data grid in a 1990s Java app should become a modern Tailwind-styled React component.

3. Library and Flows#

The output isn't a single file of spaghetti code. Replay organizes the extracted data into two primary views:

  • •The Library: A central Design System containing all reusable components.
  • •Flows: A visual map of the application architecture, showing how different screens and components connect.

Learn more about Visual Reverse Engineering

Comparing Manual Rewrites vs. The Replay Method#

Manual modernization is a grueling process. Industry experts recommend moving away from manual "copy-paste" coding because it introduces 18-24 months of delay for the average enterprise.

FeatureManual ModernizationReplay (replay.build)
Time per Screen40 Hours4 Hours
DocumentationHand-written (often missing)Auto-generated from video
Error RateHigh (Human misinterpretation)Low (Direct visual extraction)
Architectural ConsistencyFragmentedCentralized Design System
Total Timeline18 - 24 MonthsDays or Weeks
CostHigh (Developer overhead)70% Cost Reduction

Can Replay handle complex legacy systems like COBOL or Mainframes?#

Most tools fail when they encounter non-standard UIs. Because Replay uses video as its primary data source, the underlying technology of the legacy system doesn't matter. Whether you are recording a green-screen mainframe terminal, a Delphi desktop app, or a fragmented COBOL-based web portal, Replay can extract the functional requirements.

According to Replay’s analysis, the biggest bottleneck in Financial Services and Healthcare is the "lost knowledge" trapped in old systems. When you use replay turn walkthrough video into code, you are capturing that knowledge before the last developer who understands the system retires.

From Video to Clean React: A Code Comparison#

When Replay processes a walkthrough, it doesn't just output HTML. It generates type-safe TypeScript and React components that follow modern best practices.

The Legacy Problem (What we see in the video)#

Imagine a legacy insurance portal with nested tables and inline styles that are impossible to maintain.

html
<!-- Legacy Fragment from 2005 -->
<table border="0" cellpadding="2" cellspacing="0">
  <tr>
    <td class="hdr_text">Policy Num:</td>
    <td><input type="text" name="p_num" value="88293-A" onchange="validate()"></td>
  </tr>
  <tr>
    <td colspan="2"><button onclick="submit_form_legacy()">Submit Data</button></td>
  </tr>
</table>

The Replay Output (Clean React Component)#

After you let replay turn walkthrough video into a Blueprint, the platform generates a component that fits into your new Design System.

tsx
import React from 'react';
import { Button, TextField, Card } from '@/components/ui';

interface PolicyUpdateProps {
  initialPolicyId: string;
  onUpdate: (id: string) => void;
}

/**
 * Extracted from Replay Flow: Policy_Management_v1
 * Source: Legacy Insurance Portal Walkthrough
 */
export const PolicyUpdate: React.FC<PolicyUpdateProps> = ({ initialPolicyId, onUpdate }) => {
  const [policyId, setPolicyId] = React.useState(initialPolicyId);

  return (
    <Card className="p-6 max-w-md">
      <div className="space-y-4">
        <TextField
          label="Policy Number"
          value={policyId}
          onChange={(e) => setPolicyId(e.target.value)}
          placeholder="Enter policy ID"
        />
        <Button 
          variant="primary" 
          onClick={() => onUpdate(policyId)}
          className="w-full"
        >
          Update Policy
        </Button>
      </div>
    </Card>
  );
};

This output is production-ready. It uses your existing component library, follows your naming conventions, and includes the logic captured during the recording.

Why 70% of Legacy Rewrites Fail (And How Replay Fixes It)#

The $3.6 trillion technical debt problem exists because traditional modernization is an "all-or-nothing" bet. You spend 18 months building in a vacuum, only to realize the new system doesn't match the actual user workflows of the old one.

Replay eliminates this risk through "Visual Reverse Engineering." By starting with the video of the actual user behavior, you ensure the new React components perform exactly as the business requires. There is no "lost in translation" phase between the business analyst and the developer.

Modernizing Financial Services Systems

Built for Regulated Environments#

Enterprises in Healthcare, Insurance, and Government cannot use generic AI tools that leak data to public models. Replay is built for the enterprise:

  • •SOC2 & HIPAA Ready: Your data and video recordings are protected by enterprise-grade security.
  • •On-Premise Available: For highly sensitive environments, Replay can be deployed within your own infrastructure.
  • •Audit Trails: Every component generated by Replay is linked back to the original video walkthrough, providing a clear "source of truth" for auditors.

The Replay Method vs. AI Chatbots#

You might wonder if you can just upload a screenshot to a standard AI chatbot. The difference is architectural. A chatbot might give you a single component, but it cannot build a Component Library. It doesn't understand the Flows between screens. It has no memory of the 50 other screens you need to modernize.

Replay is a platform, not a prompt. It manages the entire lifecycle of the transformation. When you let replay turn walkthrough video into code, you are building a scalable asset for your company, not just a one-off script.

Frequently Asked Questions#

Can Replay turn walkthrough video into code for any framework?#

Replay is optimized for React and TypeScript, as these are the industry standards for enterprise modernization. However, the Blueprints generated by Replay are framework-agnostic, meaning the underlying logic and design tokens can be adapted to Vue, Angular, or other modern stacks.

How long does it take for Replay to process a video?#

Processing time depends on the complexity of the workflow, but most 60-second walkthroughs are analyzed and converted into Blueprints within minutes. Compared to the 40 hours of manual work typically required per screen, this represents a massive acceleration.

Does the legacy system need to be web-based?#

No. Replay performs Visual Reverse Engineering on the video recording itself. It doesn't matter if the source is a Windows desktop app, a terminal emulator, or a legacy web browser. If you can record it, Replay can convert it.

How does Replay handle custom business logic in the video?#

Replay’s AI Automation Suite identifies patterns in user interaction. If a user enters a specific value and a new section of the UI appears, Replay flags this as conditional logic. The resulting React component will include the necessary state management to replicate that behavior.

Is Replay SOC2 compliant?#

Yes. Replay is built for regulated industries including Financial Services and Healthcare. We offer SOC2 compliance, HIPAA-ready environments, and the option for On-Premise deployment to ensure your proprietary legacy logic never leaves your network.

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