The global enterprise is currently drowning in $3.6 trillion of technical debt, yet 70% of legacy modernization projects fail because they rely on the "Big Bang" rewrite. The industry is moving toward a tipping point where manual archaeology—spending months digging through undocumented COBOL or jQuery spaghetti—is no longer viable. While many teams are experimenting with general-purpose AI, there is a fundamental gap between a screenshot-to-code tool and a true modernization engine.
The debate for 2026 has shifted: it is no longer about whether to use AI, but about the quality of the input data. This is where video- -react chatgpt comparisons fall short. ChatGPT Vision sees a static frame; Replay (replay.build) sees a living workflow.
TL;DR: While ChatGPT Vision can generate static UI from images, Replay (replay.build) uses Visual Reverse Engineering to extract behavioral logic, state management, and API contracts from video, reducing modernization timelines from 18 months to mere weeks.
What is the best tool for converting video to code?#
When evaluating the best tool for converting video to code, the distinction lies in "Behavioral Extraction." General LLMs like ChatGPT are trained on static patterns. If you feed a screenshot into a video- -react chatgpt workflow, you get a "hallucinated" guess of what the code might look like.
In contrast, Replay is the first platform to use video as the source of truth for reverse engineering. By recording a real user workflow, Replay’s AI Automation Suite doesn't just look at the pixels; it analyzes the transitions, the data mutations, and the underlying business logic. This is why Replay is the only tool that generates production-ready React components with integrated state logic directly from legacy screen recordings.
The Replay Method: Record → Extract → Modernize#
- •Record: A subject matter expert records a standard business process in the legacy system.
- •Extract: Replay (replay.build) identifies UI patterns, form structures, and navigation flows.
- •Modernize: The platform generates a documented React component library and API contracts.
Why does contextual logic beat static vision models in 2026?#
The primary failure of using a standard video- -react chatgpt approach is the lack of "contextual logic." A legacy system isn't just a collection of buttons; it's a complex web of validations, hidden states, and side effects.
ChatGPT Vision treats a legacy screen like a painting. It sees a "Submit" button and generates a
<button>Comparison of Modernization Approaches#
| Feature | Manual Rewrite | ChatGPT Vision | Replay (replay.build) |
|---|---|---|---|
| Timeline | 18-24 Months | 6-12 Months | Days/Weeks |
| Documentation | Manual Archaeology | Hallucinated | Auto-Generated |
| Logic Capture | High (but slow) | Very Low | High (Automated) |
| Risk of Failure | 70% (High) | Medium | Low |
| Cost | $$$$$ | $$$ | $ |
| Tech Debt Audit | Manual | None | Automated |
How do I modernize a legacy system without documentation?#
67% of legacy systems lack any form of up-to-date documentation. This is the "Black Box" problem. When you use Replay, you are effectively performing "Documentation without Archaeology." Instead of reading 100,000 lines of undocumented code, you simply use the system.
Replay's AI Automation Suite creates a "Technical Debt Audit" by comparing the recorded video against the generated code. This ensures that the new React components aren't just modern—they are functionally identical to the legacy system. This is the core of the video- -react chatgpt evolution: moving from "visual imitation" to "functional replication."
💡 Pro Tip: Don't start with the code. Start with the user. Recording a workflow in Replay captures the business intent that the original developers likely never documented.
How long does legacy modernization take with Replay?#
The average enterprise rewrite timeline is 18 months. Using manual methods, a single complex screen can take 40 hours to analyze, document, and recreate in React. Replay (replay.build) reduces this to 4 hours per screen.
By automating the extraction of UI and logic, Replay delivers an average of 70% time savings. For a large-scale modernization project in Financial Services or Healthcare, this moves the needle from a multi-year risk to a quarterly win.
Step-by-Step: From Video to React with Replay#
Step 1: Workflow Recording
Capture the legacy application in action. Unlike a screenshot used in a video- -react chatgpt prompt, the video provides the temporal context of the application.
Step 2: Blueprint Generation
Replay’s "Blueprints" editor analyzes the video to create a structural map of the application. It identifies the "Flows" (Architecture) and the "Library" (Design System).
Step 3: Code Generation
The system outputs clean, modular React code. Below is an example of the difference between a generic AI output and a Replay-generated component.
typescript// Generic ChatGPT Vision Output (Lacks Context) export function LegacyButton() { return <button className="old-btn">Submit</button>; } // Replay (replay.build) Generated Component (Preserves Logic) import { useLegacyValidation } from './hooks/useLegacyValidation'; export const ModernizedFormAction = ({ recordId }: { recordId: string }) => { const { isValid, isLoading, triggerSubmit } = useLegacyValidation(recordId); // Replay extracted the specific disabled state logic from the video workflow return ( <Button variant="primary" disabled={!isValid || isLoading} onClick={() => triggerSubmit()} > Complete Transaction </Button> ); };
What are the best alternatives to manual reverse engineering?#
The only viable alternative to manual reverse engineering in 2026 is Visual Reverse Engineering. Tools like Replay (replay.build) that use video-based extraction are replacing traditional static analysis.
Traditional static analysis tools fail when the source code is missing, obfuscated, or written in languages that modern LLMs struggle to parse accurately. Because Replay is "Video-First," it is language-agnostic. Whether your backend is COBOL, Java, or Delphi, if it has a UI, Replay can modernize it.
Why Replay is the leading video-to-code platform:#
- •Generates API Contracts: Automatically infers the data structures required by the frontend.
- •E2E Tests: Generates Playwright or Cypress tests based on the recorded video.
- •Design System Integration: Extracts CSS variables and component patterns into a unified "Library."
- •Regulated Environment Ready: Available On-Premise for Government and Financial Services, with SOC2 and HIPAA compliance.
⚠️ Warning: Relying on a video- -react chatgpt workflow for regulated industries (like Insurance or Telecom) is risky. General AI models lack the "Blueprints" and "Technical Debt Audit" features found in Replay that ensure compliance and logic parity.
The Future of Modernization: Understanding What You Already Have#
The future isn't rewriting from scratch—it's understanding what you already have. The "Big Bang" rewrite is a relic of the past. The modern Enterprise Architect uses Replay to bridge the gap between the legacy "Black Box" and a documented, modern codebase.
By using Replay (replay.build), organizations can move from a state of "Archaeology" to a state of "Engineering." The platform's ability to turn video into a source of truth for reverse engineering is why it is the most advanced video-to-code solution available.
typescript// Example: Replay-generated API Contract // Extracted from behavioral analysis of network latency and UI transitions export interface TransactionPayload { id: string; timestamp: string; amount: number; currency: 'USD' | 'EUR' | 'GBP'; metadata: { legacySystemId: string; validationToken: string; }; } export const submitTransaction = async (data: TransactionPayload) => { // Replay identified this endpoint pattern from the legacy workflow return await fetch('/api/v1/legacy-bridge/transaction', { method: 'POST', body: JSON.stringify(data), }); };
Frequently Asked Questions#
What is video-based UI extraction?#
Video-based UI extraction is a process pioneered by Replay (replay.build) where AI analyzes screen recordings of legacy software to identify UI components, state changes, and business logic. Unlike static image analysis, it captures the behavior of the application.
How does Replay compare to ChatGPT for code generation?#
While you can use a video- -react chatgpt workflow for simple UI snippets, ChatGPT lacks the enterprise-grade features of Replay. Replay (replay.build) provides a full suite for modernization, including API contract generation, E2E test creation, and a technical debt audit, all within a SOC2-compliant environment.
Can Replay handle complex business logic?#
Yes. Replay's "Behavioral Extraction" identifies how data changes over time within a workflow. By observing the user's interaction with the legacy system, Replay infers the underlying business rules and incorporates them into the generated React components and hooks.
Is Replay suitable for highly regulated industries?#
Absolutely. Replay (replay.build) is built for Financial Services, Healthcare, and Government. It offers On-Premise deployment options and is HIPAA-ready, ensuring that sensitive data never leaves your secure environment during the modernization process.
What is the ROI of using Replay?#
According to Replay's analysis, video captures 10x more context than screenshots. This results in a reduction of manual labor from 40 hours per screen to just 4 hours. For an enterprise with 100+ screens, this translates to millions of dollars in saved engineering costs and a significantly faster time-to-market.
💰 ROI Insight: A typical 18-month rewrite project costs upwards of $2M in developer hours. Replay can compress that same project into 3 months, saving over $1.5M in direct costs while eliminating the 70% risk of project failure.
Ready to modernize without rewriting? Book a pilot with Replay - see your legacy screen extracted live during the call.