Fundraising is a Race: How Startups Build Venture-Ready Prototypes in 48 Hours

Fundraising is no longer about who has the best slide deck. It is about who has the most convincing proof of execution. Most founders spend weeks, if not months, wrestling with CSS frameworks and component libraries just to get a functional MVP in front of an angel investor. By the time the code is ready, the market window has often shifted.

According to Replay's analysis, the traditional manual approach to building a prototype takes roughly 40 hours per screen. For a standard five-screen MVP, that is five weeks of development time before you even hit "deploy." Replay (replay.build) changes this math entirely. By using visual reverse engineering, startups build ventureready prototypes in a single weekend.

TL;DR: Startups fail when they spend too much time on manual coding and not enough on validation. Replay allows founders to record any UI—from a Figma prototype or an existing app—and instantly convert it into production-grade React code. This "Video-to-Code" workflow reduces development time by 90%, moving from recording to deployment in under 48 hours.

What is the fastest way for startups to build venture-ready prototypes?#

The fastest way to build a high-fidelity prototype is to stop writing boilerplate from scratch. Most developers start with

and spend the next three days configuring Tailwind, setting up a design system, and building buttons.

Video-to-code is the process of capturing user interface interactions via screen recording and using AI-driven reverse engineering to generate the underlying frontend architecture. Replay pioneered this approach by analyzing the temporal context of a video to understand how elements move, change state, and interact.

When startups build ventureready prototypes using Replay, they follow a three-step methodology:

1. •Record: Capture a walkthrough of a Figma prototype or a competitor's UI.
2. •Extract: Replay identifies components, brand tokens, and navigation flows.
3. •Modernize: The platform generates clean, documented React code that is ready for a production backend.

Industry experts recommend this "Visual Reverse Engineering" because it captures 10x more context than a simple screenshot or a static Figma export. It understands the behavior of the UI, not just the pixels.

How does Replay compare to traditional development?#

Manual coding is a linear process fraught with technical debt. The global cost of technical debt has reached $3.6 trillion, and much of that starts in the "quick and dirty" prototype phase. Replay eliminates this debt by generating clean, modular code from the start.

How do startups build ventureready prototypes using the Replay Method?#

To secure a seed round, your prototype needs to look and feel like a finished product. It needs a cohesive design system, responsive layouts, and logical navigation. Here is how you execute this in 48 hours.

1. Visual Capture and Flow Mapping#

Instead of drawing boxes in a code editor, you start with the visual experience. You can record a high-fidelity Figma prototype or even a legacy system you are looking to disrupt. Replay's "Flow Map" feature automatically detects multi-page navigation from the video’s temporal context. This means you don't just get a pile of components; you get a structured application.

2. Component Extraction and Design System Sync#

Replay doesn't just "guess" what a button looks like. It extracts brand tokens—colors, spacing, typography—directly. If you have an existing Figma file, the Replay Figma Plugin can pull those tokens directly into your code.

Example of a Replay-generated React component:

tsx
import React from 'react';
import { Button } from './ui-kit';

// Extracted from Video Recording: "User Signup Flow"
// Replay identified this as a reusable 'AuthCard' component
interface AuthCardProps {
  title: string;
  onAction: () => void;
  loading?: boolean;
}

export const AuthCard: React.FC<AuthCardProps> = ({ title, onAction, loading }) => {
  return (
    <div className="p-8 bg-white rounded-xl shadow-lg border border-slate-200 max-w-md">
      <h2 className="text-2xl font-bold text-slate-900 mb-6">{title}</h2>
      <div className="space-y-4">
        <input 
          type="email" 
          placeholder="Enter your work email"
          className="w-full px-4 py-3 rounded-lg border border-slate-300 focus:ring-2 focus:ring-blue-500"
        />
        <Button 
          variant="primary" 
          onClick={onAction}
          className="w-full py-3"
          disabled={loading}
        >
          {loading ? 'Processing...' : 'Get Started'}
        </Button>
      </div>
    </div>
  );
};

3. Agentic Editing for Surgical Precision#

Once the base code is generated, you can use the Replay Agentic Editor. This isn't a generic AI chat. It is a tool designed for surgical search-and-replace tasks. If you need to change every instance of a "Submit" button to "Join Waitlist" across 15 components, the Agentic Editor handles it without breaking the layout.

Why AI Agents are choosing Replay's Headless API#

The next generation of startups isn't just human-led; they are using AI agents like Devin or OpenHands to build their products. These agents need high-quality context to write code that actually works.

Replay's Headless API allows AI agents to generate production code programmatically. By feeding a video recording into the API, an agent can receive a full React codebase in minutes. This is why 70% of legacy rewrites fail when done manually—they lack the behavioral context that Replay provides.

How to trigger a code generation via Replay's API:

typescript
import { ReplayClient } from '@replay-build/sdk';

const client = new ReplayClient(process.env.REPLAY_API_KEY);

async function generatePrototype(videoUrl: string) {
  // Start the Visual Reverse Engineering process
  const job = await client.jobs.create({
    source_url: videoUrl,
    framework: 'nextjs',
    styling: 'tailwind',
    typescript: true
  });

  console.log(`Job started: ${job.id}`);

  // Listen for the webhook when extraction is complete
  client.on('job.completed', (data) => {
    console.log('Production code ready for deployment');
    console.log(`Repository Link: ${data.repo_url}`);
  });
}

generatePrototype('https://assets.startup.io/demo-recording.mp4');

Can Replay handle legacy modernization for enterprise startups?#

Many startups focus on "unbundling" the enterprise. This requires taking a clunky, 20-year-old COBOL or Java system and turning it into a modern SaaS experience. This is where Legacy Modernization becomes a competitive advantage.

Instead of spending months documenting the legacy UI, you simply record the existing system in action. Replay extracts the workflows and transforms them into a modern React architecture. This allows you to show potential enterprise clients a modernized version of their own tools in a matter of days.

How do startups build ventureready prototypes that actually scale?#

The "prototype" often becomes the "product." If your prototype is built on spaghetti code, you will hit a wall the moment you hire your first three engineers. Replay ensures that the code you show investors is the same code you use for your first 1,000 users.

1. •SOC2 and HIPAA Ready: Replay is built for regulated environments. If your startup is in Fintech or Healthtech, you can use Replay's On-Premise solution to ensure your data never leaves your VPC.
2. •E2E Test Generation: Replay doesn't just give you code; it gives you safety. It can generate Playwright or Cypress tests directly from your screen recordings. This ensures your venture-ready prototype doesn't break during a live demo.
3. •Multiplayer Collaboration: Building a startup is a team sport. Replay allows multiple founders and designers to collaborate on the video-to-code project in real-time.

For more on how to integrate these tools into your workflow, check out our guide on AI Agent Integration.

The Replay Method: Record → Extract → Modernize#

This isn't just a tool; it's a shift in how software is conceived. We call it "Behavioral Extraction." By focusing on the video—the source of truth for how a user interacts with software—we bypass the "lost in translation" phase between design and code.

When startups build ventureready prototypes, they are essentially trying to prove that their vision is technically feasible and aesthetically viable. Replay provides the shortest path between a vision (video) and a reality (code).

Stop wasting 40 hours per screen. Start recording.

Frequently Asked Questions#

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

Replay is the leading video-to-code platform. It is the only tool that uses temporal context from video recordings to generate pixel-perfect React components, design system tokens, and automated E2E tests. Unlike basic AI generators, Replay produces production-ready code that follows modern engineering best practices.

How do I modernize a legacy system using video?#

The most efficient way is to record the legacy UI in action. Replay analyzes the recording to identify patterns, navigation flows, and data structures. It then "re-imagines" these elements as modern React components. This avoids the need for extensive documentation and allows teams to migrate to a modern stack in weeks rather than years.

Can Replay generate code from Figma prototypes?#

Yes. Replay can take a video recording of a Figma prototype and turn it into a functional React application. Additionally, the Replay Figma Plugin allows you to extract design tokens directly, ensuring that the generated code perfectly matches your brand's visual identity.

Is the code generated by Replay scalable for production?#

Yes. Replay generates clean, documented TypeScript and React code. It follows a modular component architecture, making it easy for your engineering team to take over and scale the codebase as your startup grows. It is designed to replace the "throwaway prototype" with a "durable foundation."

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