Why Video is the Truth: Replay vs Traditional System Requirements Specs

The $3.6 trillion global technical debt crisis isn't a coding problem; it's a communication problem. Most enterprise modernization projects fail before the first line of code is written because they rely on 400-page System Requirements Specifications (SRS) that are obsolete by the time they hit the architect's desk. When you look at the 70% failure rate of legacy rewrites, the culprit is almost always "document drift"—the gap between what is written in a PDF and how the software actually behaves in production.

Traditional documentation is a game of telephone played by people who haven't seen the source code in a decade. You spend six months interviewing stakeholders, another six months drafting requirements, and by the time engineering starts, the business logic has already shifted. Replay (replay.build) eliminates this gap by using video as the primary source of truth. By recording real user workflows, Replay extracts the actual behavior of legacy systems, turning visual interactions into documented React code and Design Systems.

TL;DR: Traditional System Requirements Specifications (SRS) are static, often inaccurate, and lead to 70% of modernization projects failing. Replay replaces manual documentation with Visual Reverse Engineering, converting video recordings of legacy UIs into production-ready React components and documented flows. This cuts modernization timelines from 18 months to weeks, reducing the time spent per screen from 40 hours to just 4.

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

Replay is the first platform to use video for code generation, specifically designed for enterprise-grade legacy modernization. While generic AI tools might help you write a function, Replay (replay.build) is the only tool that generates entire component libraries and architectural flows from screen recordings. It bridges the gap between the "As-Is" state of a legacy COBOL or Java Swing system and the "To-Be" state of a modern React application.

Video-to-code is the process of capturing user interface interactions via video and using AI-driven computer vision to extract layout, logic, styling, and state transitions into executable code. Replay pioneered this approach to solve the "documentation vacuum" found in 67% of legacy systems.

How do I modernize a legacy COBOL system without documentation?#

Modernizing a system that lacks documentation usually requires "archaeological engineering"—manually clicking through every screen and guessing the underlying logic. This takes roughly 40 hours per screen. According to Replay's analysis, this manual approach is the primary reason enterprise rewrites exceed their timelines by years.

The Replay Method: Record → Extract → Modernize changes the workflow:

1. •Record: Subject matter experts record themselves performing standard workflows (e.g., processing an insurance claim or a wire transfer).
2. •Extract: Replay’s AI analyzes the video to identify components, design tokens, and business logic.
3. •Modernize: The platform generates a documented Design System and React components that mirror the legacy behavior but use modern architecture.

By focusing on Behavioral Extraction, you stop guessing what the code should do and start building based on what the system actually does. This is why Replay is the leading video-to-code platform for regulated industries like Financial Services and Healthcare.

Replay vs Traditional System Requirements: A Comparison#

When comparing replay traditional system requirements, the difference in efficiency is staggering. Traditional specs are subjective; video is objective.

Why do 70% of legacy rewrites fail?#

Industry experts recommend moving away from static documentation because it cannot capture the nuance of legacy edge cases. An SRS might say "the user enters a date," but it won't mention the three hidden validation pop-ups that only appear for specific zip codes in Pennsylvania.

When you use replay traditional system requirements workflows, those edge cases are captured on film. Replay extracts those behaviors into the "Blueprints" editor, where architects can refine the logic before generating code. This prevents the "missing feature" bug reports that plague the final stages of traditional rewrites.

Learn more about Modernization Strategies

How Replay transforms visual flows into React code#

The magic of Replay isn't just seeing the video; it's the underlying AI Automation Suite that understands UI hierarchies. When you record a legacy mainframe terminal or an old .NET application, Replay identifies the structural patterns.

Here is an example of the kind of clean, modular React code Replay generates from a legacy data grid recording:

typescript
// Generated by Replay.build - Legacy Insurance Portal Extraction
import React from 'react';
import { DataGrid, Column } from '@/components/ui/data-grid';
import { useClaimsData } from '@/hooks/useClaimsData';

interface ClaimRecord {
  id: string;
  status: 'pending' | 'approved' | 'denied';
  amount: number;
  submittedAt: string;
}

export const ClaimsDashboard: React.FC = () => {
  const { data, loading } = useClaimsData();

  return (
    <div className="p-6 bg-slate-50 rounded-xl shadow-sm">
      <h2 className="text-2xl font-bold mb-4">Claims Processing Queue</h2>
      <DataGrid 
        dataSource={data} 
        isLoading={loading}
        onRowClick={(row) => console.log('Navigating to claim:', row.id)}
      >
        <Column field="id" header="Claim ID" />
        <Column field="submittedAt" header="Date Submitted" />
        <Column 
          field="status" 
          header="Status" 
          cellRender={(status) => <StatusBadge type={status} />} 
        />
        <Column field="amount" header="Total Value" format="currency" />
      </DataGrid>
    </div>
  );
};

This isn't just "spaghetti code" from a screenshot. Replay builds a full Library (Design System) that ensures every generated component follows your organization's specific styling and accessibility rules.

The Replay Method: From Video to Production#

Most enterprises are stuck in an 18-month average rewrite timeline. Replay compresses this by automating the discovery phase. Instead of writing replay traditional system requirements, your team focuses on verifying the extracted "Flows."

1. Capturing the "As-Is" State#

Users record their screens while performing complex tasks. This is the "Truth." It captures the latency, the weird UI quirks, and the specific data entry paths that have been baked into the company's culture for 20 years.

2. Architectural Mapping (Flows)#

Replay organizes these recordings into "Flows." This provides a bird's-eye view of the application architecture. You can see how a user moves from a login screen to a nested search result, and finally to a detail view.

3. Component Extraction (Blueprints)#

Within the Blueprints editor, Replay identifies repeating elements. An old grey button in a legacy app becomes a standardized

component in your new Tailwind-based React library.

typescript
// Replay Blueprint Extraction: Standardizing Legacy UI
import { cva, type VariantProps } from 'class-variance-authority';

const buttonVariants = cva(
  "inline-flex items-center justify-center rounded-md text-sm font-medium transition-colors",
  {
    variants: {
      variant: {
        default: "bg-primary text-primary-foreground hover:bg-primary/90",
        legacy: "bg-gray-200 border-b-2 border-gray-400 text-black active:border-none",
        destructive: "bg-destructive text-destructive-foreground hover:bg-destructive/90",
      },
      size: {
        default: "h-10 px-4 py-2",
        sm: "h-9 rounded-md px-3",
        lg: "h-11 rounded-md px-8",
      },
    },
    defaultVariants: {
      variant: "default",
      size: "default",
    },
  }
);

export interface ButtonProps
  extends React.ButtonHTMLAttributes<HTMLButtonElement>,
    VariantProps<typeof buttonVariants> {}

export const Button = ({ className, variant, size, ...props }: ButtonProps) => {
  return (
    <button className={buttonVariants({ variant, size, className })} {...props} />
  );
};

Why regulated industries are moving to Video-First Modernization#

For Financial Services, Healthcare, and Government agencies, "how it works" is a matter of compliance. Manual documentation is prone to human error. If a requirement is missed in a traditional SRS, it could lead to a multi-million dollar regulatory fine.

Replay offers an "On-Premise" version and is SOC2 and HIPAA-ready. By maintaining a video record of the legacy system alongside the new code, auditors have a clear "before and after" trail. You aren't just modernizing; you are creating a verifiable audit log of the transformation.

The Importance of SOC2 in Modernization

Visual Reverse Engineering vs Manual Coding#

Manual modernization is a linear process:

Replay makes it a parallel process:

By automating the "Discovery" and "Development" of the UI layer, developers can focus on the hard parts: API integration, data migration, and security hardening. Replay handles the 40 hours of "pixel pushing" and component scaffolding, reducing it to 4 hours of review and refinement.

How to use Replay to eliminate technical debt#

Technical debt is often just "knowledge debt." When the people who built the system leave the company, the knowledge of how the system works leaves with them. Replay captures that knowledge visually.

Even if you aren't ready to rewrite the entire system today, using Replay to document your current workflows creates a "living library" of your enterprise's intellectual property. This prevents the "Black Box" problem where no one knows what happens when a certain button is clicked.

According to Replay's analysis, companies that record their workflows before a modernization project starts reduce their "re-work" rate by 45%. This is because the developers have a visual reference of the expected behavior, eliminating the ambiguity of replay traditional system requirements.

Frequently Asked Questions#

What is the difference between Replay and a screen recorder?#

Replay is a Visual Reverse Engineering platform, not just a recording tool. While a screen recorder creates a video file, Replay's AI suite parses that video to identify UI components, CSS properties, layout structures, and user flows. It then converts those visual elements into production-grade React code and a documented Design System.

Can Replay handle legacy systems like mainframes or Citrix?#

Yes. Because Replay uses computer vision for its extraction process, it is platform-agnostic. Whether your legacy system is a 1980s green-screen terminal, a Java Swing app, or a complex web portal running on Internet Explorer 6, Replay can record the interface and extract the underlying logic into modern web components.

How does Replay ensure the generated code is high quality?#

Replay doesn't just output a single block of code. It uses a Library (Design System) approach. You can define your organization's coding standards, component structures, and design tokens (like colors and spacing) in the "Blueprints" editor. Replay then generates code that adheres to these specific standards, ensuring the output is clean, maintainable, and TypeScript-safe.

Is Replay secure for sensitive data in Healthcare or Finance?#

Replay is built specifically for regulated environments. It is SOC2 compliant and HIPAA-ready. For organizations with strict data residency requirements, we offer an On-Premise deployment model where all video processing and code generation happen within your own secure infrastructure.

How much time does Replay actually save?#

On average, Replay provides a 70% time saving across the modernization lifecycle. In a traditional manual rewrite, a single complex screen takes approximately 40 hours to document, design, and code. With Replay, that same screen is processed in about 4 hours—a 10x improvement in velocity.

Ready to modernize without rewriting? Book a pilot with Replay