Replay for Building E-Commerce Apps From UI Video: A 2026 Scalable UI Step-by-Step Guide

TL;DR: Replay lets you build scalable e-commerce UI directly from screen recordings, using AI to understand user behavior and generate production-ready code.

The future of UI development is here, and it's driven by video. Stop manually translating design mockups and user flows into code. Instead, record a video of your desired e-commerce experience, and let Replay generate the working UI for you. This guide walks you through building a scalable e-commerce application using Replay in 2026.

Why Video-to-Code is the Future for E-Commerce UI#

E-commerce development is complex. You're dealing with product listings, shopping carts, checkout flows, user accounts, and more. Traditionally, this involves:

1. •Designing mockups in Figma or similar tools.
2. •Writing code to match the designs.
3. •Testing the UI and iterating based on user feedback.

This process is time-consuming and prone to errors. Screenshot-to-code tools offer some improvements, but they lack the crucial element of understanding behavior. They can only generate static UI based on visuals. Replay takes a different approach. By analyzing video, Replay understands user intent and generates code that reflects the dynamic behavior of the UI.

💡 Pro Tip: Use clear, well-lit videos for best results with Replay. Avoid shaky camera movements and ensure all UI elements are visible.

Building Your E-Commerce UI with Replay: A Step-by-Step Guide#

This guide will walk you through building a basic e-commerce product listing page and adding a product to the shopping cart using Replay. We'll assume you have a basic understanding of React and TypeScript.

Step 1: Recording Your UI Flow#

The first step is to record a video of the desired UI flow. This video should demonstrate how a user would interact with your e-commerce application. For example:

1. •Navigate to the product listing page.
2. •Browse through the products.
3. •Select a product to view its details.
4. •Add the product to the shopping cart.

Speak clearly and narrate your actions as you record the video. This helps Replay understand your intent. For example, say "Now I'm adding this item to the cart".

📝 Note: Replay works best with clean and intuitive UI designs. Focus on creating a smooth and logical user experience in your video.

Step 2: Uploading and Processing the Video in Replay#

Once you have recorded your video, upload it to Replay. Replay's AI engine will analyze the video, identify UI elements, and understand the user interactions. This process may take a few minutes depending on the length of the video and the complexity of the UI.

Step 3: Reviewing and Refining the Generated Code#

After Replay has processed the video, you'll be presented with the generated code. This code will typically include:

• •React components for each UI element.
• •TypeScript interfaces for data models.
• •Event handlers for user interactions.
• •Basic styling using CSS-in-JS or similar techniques.

Review the generated code carefully and make any necessary refinements. You may need to adjust the styling, add missing functionality, or optimize the code for performance.

⚠️ Warning: While Replay generates functional code, it's essential to review and optimize it for production use. Pay attention to performance, security, and accessibility.

Step 4: Integrating with Supabase#

Replay offers native integration with Supabase, a popular open-source Firebase alternative. This allows you to easily connect your UI to a backend database and manage your e-commerce data.

To integrate with Supabase, follow these steps:

1. •Create a Supabase project and obtain your API keys.
2. •In Replay, configure the Supabase integration by providing your API keys and database URL.
3. •Replay will automatically generate code to fetch and update data from your Supabase database.

Here's an example of how you might fetch product data from Supabase using the generated code:

typescript
// Generated by Replay
import { createClient } from '@supabase/supabase-js';

const supabaseUrl = process.env.NEXT_PUBLIC_SUPABASE_URL;
const supabaseKey = process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY;

if (!supabaseUrl || !supabaseKey) {
  throw new Error('Supabase URL and key must be provided');
}

const supabase = createClient(supabaseUrl, supabaseKey);

export const getProducts = async () => {
  const { data, error } = await supabase
    .from('products')
    .select('*');

  if (error) {
    console.error('Error fetching products:', error);
    return [];
  }

  return data;
};

// Example usage in your component
const ProductList = async () => {
  const products = await getProducts();

  return (
    <div>
      {products.map((product) => (
        <div key={product.id}>
          <h2>{product.name}</h2>
          <p>{product.description}</p>
        </div>
      ))}
    </div>
  );
};

export default ProductList;

Step 5: Implementing Shopping Cart Functionality#

Replay can also generate code for shopping cart functionality. This includes:

• •Adding products to the cart.
• •Removing products from the cart.
• •Updating the quantity of products in the cart.
• •Calculating the total price of the cart.

The generated code will typically use local storage or cookies to persist the cart data. For a more scalable solution, you can integrate with a backend service to store the cart data in a database.

Here's an example of how you might add a product to the cart using local storage:

typescript
// Function to add a product to the cart
const addToCart = (product) => {
  // Get the current cart from local storage
  const cart = JSON.parse(localStorage.getItem('cart') || '[]');

  // Check if the product is already in the cart
  const existingProduct = cart.find((item) => item.id === product.id);

  if (existingProduct) {
    // If the product is already in the cart, increase the quantity
    existingProduct.quantity += 1;
  } else {
    // If the product is not in the cart, add it to the cart with a quantity of 1
    cart.push({ ...product, quantity: 1 });
  }

  // Save the updated cart to local storage
  localStorage.setItem('cart', JSON.stringify(cart));
};

// Example usage in your component
const ProductDetails = ({ product }) => {
  return (
    <div>
      <h2>{product.name}</h2>
      <p>{product.description}</p>
      <button onClick={() => addToCart(product)}>Add to Cart</button>
    </div>
  );
};

export default ProductDetails;

Step 6: Styling and Customization#

Replay allows you to inject custom stylesheets to customize the look and feel of your e-commerce UI. You can use CSS, Sass, or any other CSS preprocessor. Simply upload your stylesheet to Replay, and it will automatically apply the styles to the generated code.

This feature is crucial for ensuring that your UI matches your brand identity and provides a consistent user experience.

Step 7: Creating Product Flow Maps#

Replay's Product Flow Maps provide a visual representation of the user journey through your e-commerce application. This helps you understand how users navigate your site and identify potential bottlenecks or areas for improvement.

The Product Flow Maps are automatically generated based on the video analysis. You can customize the maps to highlight specific user flows and track key metrics.

Scaling Your E-Commerce Application#

Replay helps you build a solid foundation for your e-commerce application. To scale your application, consider the following:

• •Optimize your code for performance: Use techniques like code splitting, lazy loading, and caching to improve the loading speed and responsiveness of your UI.
• •Implement a robust backend: Use a scalable backend architecture like microservices to handle increasing traffic and data volumes.
• •Use a content delivery network (CDN): Distribute your static assets across a CDN to improve loading speed for users around the world.
• •Monitor your application: Use monitoring tools to track performance metrics and identify potential issues before they impact your users.

Frequently Asked Questions#

Is Replay free to use?#

Replay offers a free tier with limited features. Paid plans are available for more advanced features and higher usage limits. Check the Replay pricing page for the latest information.

How is Replay different from v0.dev?#

While both tools aim to generate code from visual inputs, Replay distinguishes itself by using video as the source of truth. This allows Replay to understand user behavior and generate dynamic UI, whereas v0.dev typically relies on static screenshots or design specifications. Replay also offers native Supabase integration and Product Flow Maps for a more comprehensive e-commerce development experience.

What kind of applications can I build with Replay?#

Replay can be used to build a wide range of applications, including e-commerce sites, dashboards, landing pages, and mobile apps. Any application with a clear UI and user flow can benefit from Replay's video-to-code capabilities.

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