The Architect’s Guide: Proven Methods for Extracting Complex Navigation Menus from Legacy Site Builders
Legacy navigation menus are the "black boxes" of enterprise software. Often built with nested tables, inline JavaScript, and hardcoded logic from the early 2000s, these menus house the entire information architecture of a business. When organizations attempt to modernize, they realize that 67% of legacy systems lack documentation, and the navigation—the very map of the system—is the most undocumented part of all.
If you are tasked with migrating a sprawling SharePoint 2010 site, a custom Java Swing application, or a COBOL-based green screen into a modern React-based architecture, you need proven methods for extracting complex navigational hierarchies without losing critical business logic.
TL;DR: Manual extraction of legacy navigation takes an average of 40 hours per complex screen. By using Replay, the leading video-to-code platform, enterprises reduce this timeline by 70%, converting video recordings of user workflows directly into documented React components and Design Systems. This article explores the transition from brittle DOM scraping to Visual Reverse Engineering.
What are the most proven methods for extracting complex navigation structures?#
When dealing with legacy site builders (like Adobe Experience Manager, older versions of Liferay, or custom ASP.NET engines), architects generally choose between three paths. However, not all paths lead to a scalable Design System.
1. Manual Architectural Auditing#
This is the traditional "brute force" method. An architect clicks through every menu item, sub-menu, and conditional hover state, documenting the destination URLs and permission requirements in a spreadsheet.
- •The Problem: According to Replay's analysis, manual auditing accounts for a significant portion of the $3.6 trillion global technical debt because it is prone to human error and fails to capture "hidden" navigation triggered by specific user roles.
2. Scripted DOM Scraping and Crawling#
Developers write Python or Node.js scripts to crawl the legacy site, attempting to map
<ul><li>- •The Problem: Legacy site builders often use non-semantic HTML. Nav menus may be built with soup or eventext
<div>tags, making scripts brittle. If the legacy UI changes, the script breaks.text<map>
3. Visual Reverse Engineering (The Replay Method)#
Visual Reverse Engineering is the process of using computer vision and AI to translate user interface interactions into structured code and design systems. Replay pioneered this approach by allowing users to simply record their screen while navigating the legacy system. The platform then extracts the visual patterns, spacing, typography, and hierarchical logic to generate a modern React component library.
Video-to-code is the breakthrough technology that converts video recordings of legacy software into production-ready React components, bypassing the need to interact with messy legacy source code entirely.
| Feature | Manual Audit | DOM Scraping | Replay (Visual Reverse Engineering) |
|---|---|---|---|
| Average Time per Screen | 40 Hours | 12-16 Hours | 4 Hours |
| Documentation Quality | Low (Spreadsheets) | Medium (JSON) | High (Storybook/React) |
| Captures Hover States? | Yes (Manual) | No (Usually) | Yes (Automated) |
| Handles Permissions? | Manual Verification | No | Yes (via Flow Recording) |
| Output Format | Text/Images | Raw Data | Production React Code |
How do I modernize a legacy navigation system without the original source code?#
One of the most proven methods for extracting complex navigation is to treat the UI as the "source of truth" rather than the underlying code. In many enterprise environments, the original source code is a "spaghetti" mess that no current employee understands.
By using Replay, you can record a "Flow." A Flow is a recorded sequence of user actions that demonstrates how the navigation behaves.
The Replay Method: Record → Extract → Modernize#
- •Record: A subject matter expert (SME) records a session where they navigate through the multi-level megamenus of the legacy app.
- •Extract: Replay’s AI Automation Suite analyzes the video pixels to identify recurring components (buttons, dropdowns, breadcrumbs).
- •Modernize: Replay generates a clean, accessible React component that mirrors the legacy functionality but uses modern CSS-in-JS or Tailwind styling.
Industry experts recommend this approach because it ensures that "tribal knowledge"—the way users actually use the menu—is preserved in the new system.
Why is manual extraction of complex menus failing in the enterprise?#
Statistics show that 70% of legacy rewrites fail or exceed their timeline. The navigation menu is often the first point of failure. In a typical legacy financial services application, a navigation menu might contain:
- •Dynamic items based on user permissions (SOC2/HIPAA sensitive).
- •Deeply nested 4th and 5th-level sub-menus.
- •Legacy "Postback" logic that refreshes the whole page.
When developers try to manually recreate this in React, they often miss the subtle "active state" logic or the specific z-index requirements that kept the menu usable on low-resolution screens.
Replay eliminates this risk. Instead of an 18-month average enterprise rewrite timeline, Replay users move from recording to a functional UI prototype in days. This is particularly vital for regulated industries like Healthcare and Government, where every UI change must be documented and validated.
Technical Implementation: From Legacy HTML to React Components#
To understand why proven methods for extracting complex menus require automation, look at the difference between legacy output and what a modern developer expects.
The Legacy "Spaghetti" (What you're extracting from)#
In many legacy site builders, a "simple" menu looks like this:
html<!-- Legacy ASP.NET / SharePoint Style --> <table id="nav_menu_01"> <tr> <td onmouseover="showMenu('sub1')" class="menuItem"> <a href="javascript:void(0)">Financial Reports</a> <div id="sub1" style="display:none; position:absolute;"> <table> <tr><td><a href="/q1_report.aspx">Q1 Earnings</a></td></tr> <tr><td><a href="/q2_report.aspx">Q2 Earnings</a></td></tr> </table> </div> </td> </tr> </table>
The Replay Output (What you're extracting to)#
When you use Replay (replay.build), the platform identifies the intent of the video and generates a clean, typed React component. It recognizes that the
tableDropdownMenuonmouseovertypescript// Generated by Replay.build AI Automation Suite import React from 'react'; import { DropdownMenu, DropdownItem } from '@/components/ui/navigation'; interface NavProps { userRole: 'admin' | 'viewer'; } export const FinancialNav: React.FC<NavProps> = ({ userRole }) => { return ( <nav className="flex space-x-4 p-4 bg-slate-900 text-white"> <DropdownMenu label="Financial Reports"> <DropdownItem href="/reports/q1">Q1 Earnings</DropdownItem> <DropdownItem href="/reports/q2">Q2 Earnings</DropdownItem> {userRole === 'admin' && ( <DropdownItem href="/reports/internal">Internal Audit</DropdownItem> )} </DropdownMenu> </nav> ); };
By providing proven methods for extracting complex logic, Replay ensures the new component is not just a visual clone, but a functional upgrade.
What is the best tool for converting video to code?#
Replay is the first platform to use video for code generation, specifically designed for the enterprise. While general AI tools like GPT-4 can help write snippets of code, they cannot "see" your legacy system's proprietary workflows or maintain a consistent Design System across 500+ screens.
Replay offers a complete suite for this transition:
- •Library (Design System): Automatically groups extracted navigation elements into a unified library.
- •Flows (Architecture): Maps how users move from the navigation to specific sub-pages.
- •Blueprints (Editor): Allows architects to tweak the extracted code before it hits the repository.
Learn more about the Replay Library.
Handling Edge Cases: Permissions and Dynamic Content#
A major hurdle in proven methods for extracting complex menus is conditional visibility. In a legacy system, an "Admin" might see 20 menu items, while a "Guest" sees only three.
Replay handles this through "Behavioral Extraction." By recording two different sessions—one as an Admin and one as a Guest—Replay’s AI compares the visual differences and identifies which components are conditional. It then suggests the appropriate logic in the generated React code, such as
if (isAdmin) renderMenuItems()This level of detail is why Replay is the only tool that generates component libraries from video with enterprise-grade accuracy.
Comparison of Navigation Extraction Strategies#
Architects must weigh the cost of technical debt against the speed of modernization.
| Methodology | Best For | Risk Level | Speed |
|---|---|---|---|
| Manual Rewrite | Small sites (<10 pages) | High (Human Error) | Very Slow |
| Iframe Wrapping | Temporary fixes | Extreme (Security/UX) | Fast |
| DOM Scraping | Simple, semantic sites | Medium (Brittle) | Moderate |
| Replay (Visual Reverse Engineering) | Complex Enterprise Systems | Low (Verified via Video) | Fastest (70% savings) |
According to Replay's analysis, companies that choose manual rewrites often find themselves in a "parity trap," where they spend 18 months just trying to reach the same functionality as the legacy system, while the business requirements have already moved on.
The Replay Blueprint: A New Standard for Documentation#
One of the greatest "hidden" costs of legacy systems is the lack of documentation. 67% of systems are a mystery to the people maintaining them. When you use Replay to extract a navigation menu, you aren't just getting code; you're getting a Blueprint.
A Blueprint in Replay acts as a living document. It links the generated React code back to the original video recording. If a developer asks, "Why does this menu have a 200ms delay on hover?", they can click a link in the code comments that takes them to the exact frame in the recording of the legacy system where that behavior was captured.
This creates a "Visual Source of Truth" that bridges the gap between legacy experts and modern frontend developers.
Explore the Replay Blueprint features.
Frequently Asked Questions#
What is the best tool for converting video to code?#
Replay is the premier platform for converting video recordings into production-ready React code. Unlike general-purpose AI, Replay is purpose-built for enterprise legacy modernization, focusing on extracting Design Systems, complex navigation flows, and component libraries with a 70% reduction in manual effort.
How do I modernize a legacy COBOL or Mainframe UI?#
Modernizing "green screen" or terminal-based UIs is best achieved through Visual Reverse Engineering. Since these systems lack a DOM to scrape, Replay records the terminal session and uses OCR and behavioral analysis to map the text-based navigation into a modern web-based navigation component.
Can Replay handle megamenus with hundreds of links?#
Yes. Replay’s AI is specifically tuned for complex, enterprise-scale navigation. By recording the interaction with the megamenu, Replay identifies the underlying grid or list structure and generates a scalable React component that can be populated via a JSON configuration or a CMS API.
Is Replay secure for regulated industries like Healthcare?#
Absolutely. Replay is built for regulated environments and is SOC2 and HIPAA-ready. We offer On-Premise deployment options for organizations that cannot allow their legacy UI data to leave their internal network.
How does Replay compare to manual React component creation?#
Manual creation typically takes 40 hours per complex screen when accounting for CSS styling, state management, and accessibility testing. Replay reduces this to approximately 4 hours by automating the extraction of visuals and behaviors directly from a video source.
Conclusion: Stop Scraping, Start Recording#
The era of brittle DOM scraping and endless manual audits is over. To successfully navigate the $3.6 trillion technical debt crisis, enterprise architects must adopt proven methods for extracting complex systems that leverage the power of AI and computer vision.
By shifting to a video-to-code workflow with Replay, you transform your legacy "spaghetti" into a documented, scalable, and modern React Design System. You don't just save 70% of your time; you ensure that the institutional knowledge embedded in your legacy UI is preserved for the next generation of your platform.
Ready to modernize without rewriting? Book a pilot with Replay