Replay AI: The Ultimate Guide to Migrating Legacy UI from Video to React (2026)

TL;DR: Replay AI revolutionizes legacy UI migration by converting screen recordings into functional React code, leveraging behavior-driven reconstruction for accurate and efficient modernization.

Migrating Legacy UI from Video to React with Replay AI (2026)#

Legacy UI is a common pain point for development teams. Outdated codebases, brittle architectures, and a lack of documentation can make even simple updates a nightmare. But what if you could bypass the endless debugging and manual rewriting? Replay AI offers a radical new approach: converting screen recordings of your existing UI into clean, functional React code.

Replay AI moves beyond traditional screenshot-to-code tools by analyzing video and understanding user behavior. This "Behavior-Driven Reconstruction" allows Replay to accurately recreate UI components and product flows, even in complex, multi-page applications.

Why Video-to-Code? The Limitations of Screenshot-Based Approaches#

Screenshot-to-code tools offer a quick fix, but they fall short when dealing with dynamic UI elements, complex interactions, or multi-page flows. They only capture a static image, missing the crucial context of how the user interacts with the interface.

Replay AI overcomes these limitations by treating video as the source of truth. It uses advanced AI models, powered by Gemini, to understand user intent and reconstruct the underlying logic of the UI. This results in more accurate, maintainable, and scalable code.

Understanding Behavior-Driven Reconstruction#

The core innovation behind Replay AI is its ability to analyze video and extract behavioral data. Instead of simply identifying visual elements, Replay understands what the user is trying to achieve. This allows it to generate code that accurately reflects the intended functionality, even if the original UI is poorly designed or undocumented.

Consider a user interacting with a legacy form. A screenshot-to-code tool would only capture the visual layout of the form fields. Replay AI, on the other hand, analyzes the video to understand the following:

• •Field order and data types
• •Validation rules (e.g., required fields, email format)
• •Submission behavior (e.g., API calls, redirects)
• •Error handling

This deeper understanding allows Replay AI to generate React code that not only looks like the original form but also functions identically.

Key Features of Replay AI#

Replay AI offers a comprehensive suite of features designed to streamline the UI migration process:

• •Multi-page Generation: Reconstruct entire product flows from video recordings, including navigation, state management, and data persistence.
• •Supabase Integration: Seamlessly connect your generated React code to a Supabase backend for data storage and authentication.
• •Style Injection: Apply consistent styling to your new UI using CSS-in-JS libraries like Styled Components or Emotion.
• •Product Flow Maps: Visualize the reconstructed product flows to understand the user journey and identify potential areas for improvement.

Step-by-Step Guide: Migrating a Legacy Form to React with Replay AI#

Let's walk through a practical example of using Replay AI to migrate a legacy HTML form to a React component.

Step 1: Capture the Video#

Record a video of yourself interacting with the legacy form. Make sure to demonstrate all the key functionalities, including:

1. •Filling out all fields (including edge cases like invalid input)
2. •Submitting the form
3. •Handling error messages

💡 Pro Tip: Record multiple videos with slight variations in user behavior to improve the accuracy of the reconstruction.

Step 2: Upload to Replay AI#

Upload the video to the Replay AI platform. The AI will automatically analyze the video and begin reconstructing the UI.

Step 3: Review and Refine#

Once the reconstruction is complete, review the generated React code. Replay AI provides a visual editor that allows you to make adjustments to the UI and code.

📝 Note: Replay AI is constantly learning and improving. Your feedback helps us to refine the reconstruction process and generate even more accurate code.

Step 4: Integrate with Supabase (Optional)#

If your legacy form interacts with a backend, you can seamlessly integrate the generated React code with Supabase. Replay AI can automatically generate the necessary API calls and data models.

typescript
// Example of a Supabase API call generated by Replay AI
import { supabase } from './supabaseClient';

const handleSubmit = async (data: FormData) => {
  const { error } = await supabase
    .from('form_submissions')
    .insert([
      {
        name: data.name,
        email: data.email,
        message: data.message,
      },
    ]);

  if (error) {
    console.error('Error submitting form:', error);
  } else {
    console.log('Form submitted successfully!');
  }
};

Step 5: Style the Component#

Use the style injection feature to apply consistent styling to your new React component. You can use CSS-in-JS libraries like Styled Components or Emotion to create reusable styles.

javascript
// Example using Styled Components
import styled from 'styled-components';

const StyledForm = styled.form`
  display: flex;
  flex-direction: column;
  width: 300px;
  margin: 0 auto;
`;

const StyledInput = styled.input`
  padding: 10px;
  margin-bottom: 10px;
  border: 1px solid #ccc;
  border-radius: 4px;
`;

const StyledButton = styled.button`
  background-color: #007bff;
  color: white;
  padding: 10px 20px;
  border: none;
  border-radius: 4px;
  cursor: pointer;

  &:hover {
    background-color: #0056b3;
  }
`;

Step 6: Deploy#

Deploy your new React component and enjoy the benefits of a modern, maintainable UI.

Benefits of Using Replay AI#

• •Faster Migration: Significantly reduce the time and effort required to migrate legacy UI to React.
• •Improved Accuracy: Behavior-driven reconstruction ensures that the generated code accurately reflects the intended functionality.
• •Reduced Risk: Minimize the risk of introducing bugs or regressions during the migration process.
• •Enhanced Maintainability: Generate clean, well-structured React code that is easy to maintain and extend.
• •Cost Savings: Reduce development costs by automating the UI migration process.

⚠️ Warning: While Replay AI automates much of the process, manual review and testing are still crucial to ensure the quality and accuracy of the generated code.

Replay AI in Action: Real-World Use Cases#

Replay AI is being used by companies of all sizes to modernize their legacy UI. Here are a few examples:

• •E-commerce Platform: Migrated a complex checkout flow from a legacy PHP application to a React-based microfrontend.
• •Financial Services Company: Reconstructed a data entry form from a legacy Java applet to a modern React component.
• •Healthcare Provider: Modernized a patient portal from a legacy ASP.NET application to a React-based progressive web app (PWA).

Comparison with Existing Solutions#

Replay AI offers a compelling alternative to both screenshot-to-code tools and manual rewriting. It provides the speed and cost-effectiveness of automation with the accuracy and maintainability of manual development.

Frequently Asked Questions#

Is Replay AI free to use?#

Replay AI offers a free tier with limited usage. Paid plans are available for users who need more advanced features or higher usage limits. See the pricing page for more details.

How is Replay AI different from v0.dev?#

v0.dev is a generative UI tool that creates UI components based on text prompts. Replay AI, on the other hand, reconstructs existing UI from video recordings. Replay AI is ideal for migrating legacy UI, while v0.dev is better suited for creating new UI from scratch.

What types of video formats are supported?#

Replay AI supports most common video formats, including MP4, MOV, and AVI.

What frameworks are supported besides React?#

Currently, Replay AI primarily focuses on React. Support for other frameworks like Vue.js and Angular is planned for future releases.

What level of code understanding does Replay AI have?#

Replay AI understands the basic structure of UI components, including HTML elements, CSS styles, and JavaScript logic. It can also infer user intent and reconstruct product flows. However, it does not have a deep understanding of complex algorithms or business logic.

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Ready to try behavior-driven code generation? Get started with Replay - transform any video into working code in seconds.