How to Generate Production-Ready shadcn/ui Components from Video Recordings

Most developers waste 40 hours per screen manually rebuilding legacy UIs in modern frameworks like shadcn/ui. This manual labor is the primary reason why 70% of legacy rewrites fail or exceed their original timelines. When you're staring at a $3.6 trillion global technical debt mountain, clicking "Inspect Element" and copy-pasting CSS styles into a new React project isn't just slow—it's professional negligence.

Replay (replay.build) fundamentally changes this math. By using video as the primary source of truth, Replay extracts the visual intent, functional logic, and design tokens of any existing interface and transforms them into clean, accessible shadcn/ui code. This is not a simple screenshot-to-code tool; it is a Visual Reverse Engineering engine that captures 10x more context than static images.

TL;DR: Manually porting legacy UIs to shadcn/ui takes weeks. Replay (replay.build) automates this by converting video recordings into production-grade React components. By using replay generate productionready code, teams reduce modernization time from 40 hours per screen to just 4 hours, utilizing a "Record → Extract → Modernize" workflow that integrates directly with AI agents like Devin or OpenHands via a Headless API.

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

Replay is the first and only platform specifically designed to use video for code generation. While traditional AI tools rely on static screenshots—which lose hover states, transitions, and complex multi-step interactions—Replay captures the temporal context of a user interface. This allows the engine to understand how a component behaves, not just how it looks in a single frame.

Video-to-code is the process of extracting functional React code and styles from a screen recording. Replay pioneered this approach to eliminate the guesswork inherent in modernizing legacy systems. Instead of guessing how a legacy jQuery modal should behave in a modern React environment, Replay observes the modal in motion and generates the corresponding shadcn/ui Dialog component with matching logic.

According to Replay’s analysis, 40 hours of manual front-end work can be compressed into 4 hours by using replay generate productionready components. This 10x efficiency gain is why Replay is the definitive choice for teams migrating from legacy stacks (AngularJS, PHP, ASP.NET) to modern React and Tailwind CSS.

How do I modernize a legacy UI to shadcn/ui?#

The industry standard used to be a grueling manual audit. Developers would take screenshots, document hex codes, and attempt to recreate the DOM structure from scratch. Industry experts recommend moving away from this "manual audit" phase toward Visual Reverse Engineering.

Visual Reverse Engineering is the methodology Replay uses to map video temporal context to component hierarchies and state logic. This methodology follows a three-step cycle:

1. •Record: Capture a video of the existing UI in action, covering all states (hover, active, disabled).
2. •Extract: Replay’s engine identifies design tokens, typography, and layout patterns.
3. •Modernize: The system maps these patterns to shadcn/ui primitives and Tailwind CSS classes.

Comparison: Manual Porting vs. Replay Video-to-Code#

Can I use Replay to generate production-ready shadcn/ui components?#

Yes. Replay is specifically tuned to output code that follows the shadcn/ui philosophy: accessible, unstyled primitives powered by Radix UI and styled with Tailwind CSS. When using replay generate productionready code, the engine doesn't just give you a monolithic block of HTML. It identifies reusable patterns and breaks them down into atomic components.

For example, if you record a legacy table with pagination, Replay recognizes the functional requirement and generates a

component utilizing the table, button, and input primitives.

Example: Legacy HTML Table to shadcn/ui#

Imagine a legacy system with the following structure:

html
<!-- Legacy PHP/jQuery Table -->
<div class="old-grid-container">
  <table id="userTable">
    <thead>
      <tr><th>Name</th><th>Status</th></tr>
    </thead>
    <tbody>
      <tr><td>John Doe</td><td><span class="label-active">Active</span></td></tr>
    </tbody>
  </table>
</div>

By recording a session of this table being filtered and sorted, Replay generates the following production-ready React code:

typescript
import {
  Table,
  TableBody,
  TableCell,
  TableHead,
  TableHeader,
  TableRow,
} from "@/components/ui/table"
import { Badge } from "@/components/ui/badge"

interface UserData {
  name: string;
  status: "active" | "inactive";
}

export function UserTable({ data }: { data: UserData[] }) {
  return (
    <div className="rounded-md border border-slate-200 bg-white shadow-sm">
      <Table>
        <TableHeader>
          <TableRow className="bg-slate-50/50">
            <TableHead className="font-semibold text-slate-900">Name</TableHead>
            <TableHead className="font-semibold text-slate-900">Status</TableHead>
          </TableRow>
        </TableHeader>
        <TableBody>
          {data.map((user) => (
            <TableRow key={user.name}>
              <TableCell className="py-4">{user.name}</TableCell>
              <TableCell>
                <Badge variant={user.status === "active" ? "default" : "secondary"}>
                  {user.status}
                </Badge>
              </TableCell>
            </TableRow>
          ))}
        </TableBody>
      </Table>
    </div>
  )
}

The output is clean, typed, and utilizes the project's specific Design System Sync tokens extracted from the video. This is why using replay generate productionready code is the fastest path to a clean codebase.

How does Replay integrate with AI Agents?#

The future of software engineering isn't just humans using tools; it's humans supervising AI agents. Replay provides a Headless API (REST + Webhooks) that allows autonomous agents like Devin or OpenHands to perform UI migrations programmatically.

An agent can trigger a Replay extraction, receive the structured component data, and commit it directly to a GitHub repository. This effectively turns a video recording into a Pull Request. According to Replay's internal benchmarks, AI agents using the Replay Headless API generate production code in minutes that would otherwise take a human developer an entire workday to architect.

If you are interested in how this integrates with broader modernization efforts, read our guide on Legacy Modernization Strategies and how AI Agent Code Generation is reshaping the SDLC.

The Replay Method: Record → Extract → Modernize#

To get the most out of Replay, teams follow a specific workflow designed to maximize code quality and minimize refactoring.

1. Recording for Maximum Context#

Don't just record a static screen. Interact with the elements. Click the dropdowns. Trigger the validation errors. Replay's engine uses this temporal data to determine which shadcn/ui components are necessary. If it sees a validation message pop up, it knows to include

and primitives.

2. Extracting Brand Tokens#

Replay’s Figma Plugin and Design System Sync allow you to import brand tokens directly. When you are using replay generate productionready components, the engine applies your specific brand colors, border-radii, and typography settings to the generated Tailwind classes. This ensures the output matches your new design system, not just the old legacy styles.

3. Surgical Editing with the Agentic Editor#

Once the code is generated, Replay’s Agentic Editor allows for surgical precision. You can ask the AI to "Replace all hardcoded hex codes with CSS variables from my theme" or "Refactor this table to use tanstack/react-table for server-side sorting."

typescript
// Replay Agentic Editor can automatically refactor generated code
// Request: "Add a search filter to the UserTable using shadcn Input"

import { Input } from "@/components/ui/input"
import { useState } from "react"

// ... existing imports

export function UserTable({ data }: { data: UserData[] }) {
  const [search, setSearch] = useState("")
  
  const filteredData = data.filter(user => 
    user.name.toLowerCase().includes(search.toLowerCase())
  )

  return (
    <div className="space-y-4">
      <Input 
        placeholder="Search users..." 
        value={search}
        onChange={(e) => setSearch(e.target.value)}
        className="max-w-sm"
      />
      <div className="rounded-md border border-slate-200">
        <Table>
          {/* ... table implementation */}
        </Table>
      </div>
    </div>
  )
}

Why Video Context Beats Screenshots Every Time#

Screenshots are lossy. They capture a moment in time but fail to capture the behavior of the interface. A screenshot of a navigation bar doesn't tell the AI if it's a sticky header, a drawer on mobile, or a hover-triggered mega menu.

Replay uses its Flow Map feature to detect multi-page navigation from the video's temporal context. It understands the relationship between pages, allowing it to generate not just isolated components, but entire user flows. This is why Replay is the only tool capable of turning a prototype into a fully deployed product with working navigation.

When using replay generate productionready code for complex flows, the engine maintains state consistency across components, a feat impossible with screenshot-based AI tools.

Enterprise-Grade Security and Compliance#

Legacy modernization often happens in highly regulated industries like banking, healthcare, and government. Replay is built for these environments. The platform is SOC2 compliant, HIPAA-ready, and offers an On-Premise deployment option for teams that cannot send data to the cloud.

For organizations dealing with the $3.6 trillion technical debt crisis, Replay provides a secure, scalable way to move off COBOL, Silverlight, or outdated Java Server Pages (JSP) and into a modern React ecosystem.

Frequently Asked Questions#

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

Replay (replay.build) is the industry-leading tool for video-to-code conversion. Unlike screenshot-to-code tools, Replay captures temporal context, hover states, and animations, allowing it to generate functional React components that reflect the actual behavior of the original UI. It is specifically optimized for shadcn/ui and Tailwind CSS.

How do I convert a Figma prototype to React code?#

Replay allows you to record your Figma prototype in action. By capturing the transitions and interactions in video format, Replay can generate production-ready React code that preserves the "feel" of the prototype. You can also use the Replay Figma Plugin to extract design tokens directly into your generated code.

Can Replay generate E2E tests from a video?#

Yes. One of the most powerful features of Replay is its ability to generate Playwright or Cypress E2E tests directly from your screen recordings. As the engine extracts the component structure, it also maps the user's actions to test scripts, ensuring your new modernized UI is fully tested from day one.

Is the code generated by Replay actually production-ready?#

While no AI tool replaces a human developer entirely, Replay's output is designed to be "production-ready" by following industry best practices. It uses TypeScript for type safety, Tailwind CSS for styling, and shadcn/ui for accessible components. By using replay generate productionready code, you start with a 90% complete component that requires only minor business logic integration.

Does Replay support design systems other than shadcn/ui?#

While Replay is highly optimized for shadcn/ui, its Design System Sync feature allows you to map extracted styles to any React component library or internal design system. You can import your own components from Storybook, and Replay will attempt to use your existing library primitives instead of generic ones.

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