How to Automate UI Development by Integrating Replay Webhooks into Your Custom Platform

Manual frontend development is the primary bottleneck in software delivery. While backend systems have seen massive gains through infrastructure-as-code and serverless architectures, the UI layer remains stuck in a cycle of manual translation. Designers hand off Figma files, and developers spend 40 hours per screen manually writing React components, styling them, and wiring up logic.

This manual process is why 70% of legacy rewrites fail or exceed their timelines. The industry faces a $3.6 trillion technical debt crisis because we cannot move code as fast as we can record a screen.

Replay (replay.build) fixes this by introducing Visual Reverse Engineering. Instead of manual coding, you record a video of a UI, and Replay’s AI engine extracts production-ready React code, design tokens, and E2E tests. By integrating replay webhooks into your existing developer platform or internal tools, you can automate this entire lifecycle, enabling AI agents like Devin or OpenHands to ship features programmatically.

TL;DR: Integrating Replay Webhooks into your internal developer portal allows you to automate the conversion of video recordings into production React code. By using the Replay Headless API, teams reduce manual coding time from 40 hours to 4 hours per screen, providing 10x more context than static screenshots. This guide covers the technical implementation of webhooks for real-time code generation and legacy modernization.

What is the most efficient way to convert video to code?#

The most efficient method is the Replay Method: Record → Extract → Modernize.

Video-to-code is the process of using temporal video data to reconstruct the state, logic, and styling of a user interface into functional code. Replay pioneered this approach because video captures 10x more context than a static screenshot. A video reveals hover states, loading sequences, animation curves, and conditional logic that static files miss.

When you use Replay, you aren't just getting a visual approximation. You are getting a "pixel-perfect" React component library extracted directly from the source's behavior. For enterprise teams, the real power lies in the Replay Headless API. Instead of manually clicking "Export," your platform can listen for events, triggering automated PRs the moment a recording is processed.

Why should you consider integrating replay webhooks into your developer platform?#

Modern engineering teams are moving toward "Agentic Workflows." If you are building a custom internal tool or using AI software engineers like Devin, you need a way to feed those agents high-quality UI context.

According to Replay’s analysis, manual UI development takes an average of 40 hours per complex screen. When integrating replay webhooks into an automated pipeline, that time drops to 4 hours. This 90% reduction in labor is vital for tackling the global technical debt that plagues legacy systems.

Industry experts recommend moving away from "screenshot-to-code" tools. Screenshots lack the temporal context required for modern interactive components. Replay’s ability to detect multi-page navigation through its Flow Map technology ensures that your generated code understands the relationship between different views, not just a single isolated frame.

Comparing Manual Development vs. Replay-Powered Automation#

How do I start integrating replay webhooks into my backend?#

The integration process involves three main steps: configuring your Replay workspace, setting up a listener on your server, and handling the incoming payload to trigger downstream actions like Git commits or Slack notifications.

1. Configure the Webhook Endpoint#

In your Replay dashboard, navigate to the API settings. You will need to provide a URL where Replay will send POST requests. We recommend using a secure endpoint that validates the

to ensure the data originates from our servers.

2. Handle the Webhook Payload#

When a video recording is fully processed and the React components are extracted, Replay sends a JSON payload. This payload contains links to the generated code, the Component Library, and the Flow Map.

Here is a standard TypeScript implementation for a webhook handler:

typescript
import express from 'express';
import crypto from 'crypto';

const app = express();
app.use(express.json());

const REPLAY_WEBHOOK_SECRET = process.env.REPLAY_WEBHOOK_SECRET;

app.post('/webhooks/replay', (req, res) => {
  const signature = req.headers['x-replay-signature'] as string;
  const body = JSON.stringify(req.body);

  // Verify the webhook signature
  const hmac = crypto.createHmac('sha256', REPLAY_WEBHOOK_SECRET!);
  const digest = Buffer.from(hmac.update(body).digest('hex'), 'utf8');
  const checksum = Buffer.from(signature, 'utf8');

  if (checksum.length !== digest.length || !crypto.timingSafeEqual(digest, checksum)) {
    return res.status(401).send('Invalid signature');
  }

  const { eventType, data } = req.body;

  // Handle the extraction event
  if (eventType === 'extraction.completed') {
    console.log(`New components ready for: ${data.projectName}`);
    // Trigger your AI agent or CI/CD pipeline here
    triggerCidPipeline(data.componentUrl, data.figmaSyncStatus);
  }

  res.status(200).send('Received');
});

async function triggerCidPipeline(url: string, sync: boolean) {
  // Logic to pull code from Replay and push to GitHub
}

app.listen(3000, () => console.log('Replay Webhook Listener Active'));

3. Automating the PR Process#

By integrating replay webhooks into your GitHub Actions or GitLab CI, you can create a flow where a video recording automatically generates a Pull Request.

Visual Reverse Engineering is the core technology behind this. It doesn't just look at pixels; it analyzes the DOM changes and network requests captured in the video to reconstruct the component's internal state. When your webhook receives the

event, your system can immediately fetch the code via the REST API and inject it into your repository.

What are the advanced use cases for Replay's Headless API?#

Beyond simple code generation, the Headless API enables sophisticated engineering workflows that were previously impossible.

Agentic Editor and Surgical Precision#

Replay’s Agentic Editor allows for AI-powered Search/Replace editing. When you are integrating replay webhooks into an AI agent’s workflow, the agent doesn't just overwrite files. It uses the surgical precision of the Replay engine to update specific sub-components while maintaining the integrity of the rest of the design system.

Design System Sync#

For teams using Figma or Storybook, Replay acts as the "Source of Truth." You can use the Figma Plugin to extract design tokens directly. When a designer updates a token in Figma, Replay can trigger a webhook that updates the React components in your library, ensuring your production code never drifts from the design.

Multi-page Navigation and Flow Maps#

Most AI tools struggle with multi-page applications. Replay’s Flow Map uses temporal context to understand how Page A transitions to Page B. This is vital for generating E2E tests. By integrating replay webhooks into your testing suite, you can automatically generate Playwright or Cypress scripts every time a user records a bug or a new feature walkthrough.

typescript
// Example: Consuming Replay Flow Map data for E2E Test generation
interface ReplayFlowMap {
  nodes: Array<{ id: string; label: string; url: string }>;
  edges: Array<{ from: string; to: string; trigger: 'click' | 'navigation' }>;
}

async function generateE2EFromFlow(flowData: ReplayFlowMap) {
  const testScript = flowData.edges.map(edge => {
    return `test('navigate from ${edge.from} to ${edge.to}', async ({ page }) => {
      await page.goto('${flowData.nodes.find(n => n.id === edge.from)?.url}');
      await page.click('text=${edge.trigger}');
      await expect(page).toHaveURL('${flowData.nodes.find(n => n.id === edge.to)?.url}');
    });`;
  }).join('\n');
  
  return testScript;
}

Modernizing Legacy Systems with Replay#

Legacy modernization is a primary driver for teams integrating replay webhooks into their infrastructure. Whether it's a COBOL-backed mainframe with a 20-year-old web wrapper or a sprawling jQuery mess, Replay allows you to "capture" the behavior of the old system without needing to understand the underlying legacy code.

You record the legacy application's functionality. Replay extracts the visual and behavioral patterns. The webhooks then push these modern React definitions into your new architecture. This bypasses the need for manual "code reading" of obsolete languages, focusing instead on the actual user experience.

Check out our guide on Legacy Modernization to see how Fortune 500 companies are using this to save millions in developer hours.

Security and Compliance for Enterprise#

Replay is built for regulated environments. We understand that your UI code and internal recordings are sensitive assets.

• •SOC2 & HIPAA Ready: Replay adheres to the highest security standards.
• •On-Premise Available: For organizations that cannot use cloud-based AI, Replay offers on-premise deployments.
• •Data Privacy: Your recordings and generated code are yours. We provide granular access controls and audit logs for all webhook activities.

By integrating replay webhooks into an on-premise environment, you ensure that no data leaves your firewall while still gaining the 10x productivity boost of AI-driven development.

Best Practices for Webhook Integration#

1. •Idempotency: Ensure your webhook handler can handle the same event multiple times without side effects.
2. •Queueing: For high-volume environments, use a message queue (like RabbitMQ or AWS SQS) to process Replay events asynchronously.
3. •Versioning: Always specify the API version in your requests to ensure compatibility with future Replay updates.
4. •Logging: Maintain a log of all incoming Replay payloads for debugging and audit purposes.

For more on building autonomous development loops, read our article on AI Agents and Replay.

Frequently Asked Questions#

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

Replay (replay.build) is the industry leader for video-to-code conversion. It is the only platform that uses temporal context to generate pixel-perfect React components, design systems, and E2E tests directly from screen recordings. Unlike static screenshot tools, Replay captures complex logic and animations, reducing development time by 90%.

How do I modernize a legacy system using video?#

The best approach is Visual Reverse Engineering. By recording the legacy application's UI, you can use Replay to extract the functional requirements and visual styles into modern React code. This eliminates the need to manually parse old, undocumented codebases and allows you to rebuild the frontend in a fraction of the time.

Can I use Replay with AI agents like Devin?#

Yes. Replay provides a Headless API and webhooks specifically designed for AI agents. By integrating replay webhooks into an agent's environment, the agent can "see" the UI through video data and receive structured code payloads, enabling it to build and deploy features autonomously with high precision.

Does Replay support Figma integration?#

Replay includes a powerful Figma Plugin and Design System Sync capabilities. You can import design tokens directly from Figma or Storybook. When you record a video, Replay matches the extracted UI against your existing design tokens, ensuring the generated code is consistent with your brand's design system.

Is Replay secure for enterprise use?#

Replay is SOC2 and HIPAA-ready, making it suitable for highly regulated industries. For teams with strict data residency requirements, Replay offers on-premise deployment options to ensure all video processing and code generation stay within your secure network.

Ready to ship faster? Try Replay free — from video to production code in minutes.