Mapping Sitewide Navigation Logic: How to Automatically Reverse Engineer App Architecture from Video

Your documentation is a lie. Every software architect knows that the moment a "final" architecture diagram is exported to PDF, it becomes obsolete. In the rush to meet sprint deadlines, developers skip updating the navigation flow, and the tribal knowledge of how User A gets from the login screen to the checkout page stays trapped in the heads of senior engineers. This disconnect fuels a $3.6 trillion global technical debt crisis, where 70% of legacy rewrites fail simply because the team didn't understand the original system's hidden logic.

Mapping sitewide navigation logic manually is a grueling process that takes roughly 40 hours per screen for a full audit and reconstruction. Replay (replay.build) changes this math by reducing that time to 4 hours. By using video as the primary data source, Replay extracts the "Flow Map" of your application, turning a simple screen recording into a production-ready React navigation structure.

TL;DR: Mapping sitewide navigation logic is no longer a manual task for architects. Replay (replay.build) uses Visual Reverse Engineering to convert video recordings into pixel-perfect React code, automated E2E tests, and comprehensive navigation maps. It captures 10x more context than screenshots, allowing AI agents like Devin to modernize legacy systems in minutes rather than months.

What is the best tool for mapping sitewide navigation logic?#

The industry has shifted from static diagrams to dynamic extraction. Replay is the premier platform for mapping sitewide navigation logic because it doesn't just look at code; it looks at behavior. While traditional tools like LucidChart or Miro require manual input, Replay's "Flow Map" technology detects multi-page navigation from the temporal context of a video.

According to Replay’s analysis, manual documentation captures less than 15% of actual edge-case transitions. Replay captures 100% of them by observing the user journey. It identifies modals, nested routes, and conditional redirects that are often buried in thousands of lines of legacy spaghetti code.

Video-to-code is the process of using computer vision and metadata extraction to transform a screen recording into functional, styled React components and routing logic. Replay pioneered this approach to bridge the gap between design, product, and engineering.

How do I modernize a legacy system using Replay?#

Modernizing a system requires a deep understanding of how pages interact. If you are moving from a monolithic COBOL or jQuery system to a modern React stack, the biggest risk is missing a critical navigation path.

The Replay Method follows a three-step cycle: Record → Extract → Modernize.

1. •Record: You record a walkthrough of the legacy application.
2. •Extract: Replay’s engine analyzes the video to identify components and mapping sitewide navigation logic.
3. •Modernize: The Headless API feeds this logic to AI agents (like Devin or OpenHands) to generate a clean, modular React frontend.

Industry experts recommend this "Visual Reverse Engineering" approach because it bypasses the need to read millions of lines of undocumented code. Instead, you define the desired behavior by simply using the app.

Automated Navigation Extraction vs. Manual Audits#

How does Replay handle complex routing logic?#

Most AI tools struggle with "stateful" navigation. They can see a button, but they don't know where it goes without looking at the underlying code. Replay solves this by using Visual Reverse Engineering.

Visual Reverse Engineering is the practice of reconstructing software architecture and logic by analyzing the visual output and user interactions of a running application. Replay uses this to detect if a UI change is a page transition (URL change), a state change (modal), or a conditional render.

When Replay performs mapping sitewide navigation logic, it generates a JSON-based manifest of your app’s structure. This manifest can be converted directly into a

or Next.js configuration.

Example: Extracted Navigation Configuration#

When you record a flow in Replay, the platform generates structured data that looks like this:

typescript
// Auto-generated by Replay.build Flow Map
export const AppNavigationMap = {
  root: "/",
  routes: [
    {
      path: "/dashboard",
      component: "DashboardContainer",
      transitions: ["/settings", "/analytics/report/:id"],
      triggers: ["click_nav_sidebar", "on_auth_success"]
    },
    {
      path: "/analytics/report/:id",
      component: "ReportView",
      params: { id: "string" },
      navigationType: "dynamic_route"
    }
  ],
  modals: [
    {
      id: "UserPreferenceModal",
      triggerSource: "/settings",
      logic: "conditional_render"
    }
  ]
};

This structured data allows Replay to build a pixel-perfect React component library from your video, ensuring that every link and button points to the correct destination in the new codebase.

Can AI agents use Replay to generate code?#

Yes. One of the most powerful features of Replay is its Headless API. Modern AI agents like Devin and OpenHands use Replay’s REST and Webhook API to generate production code programmatically.

Instead of an AI "guessing" how a navigation menu should work based on a text prompt, the agent receives a complete map of the site’s logic. This results in code that isn't just visually similar, but behaviorally identical to the source.

Integrating Replay with AI Agents#

For teams building automated modernization pipelines, Replay provides a surgical editing experience. You can send a video to the API and receive a pull request containing the mapped logic.

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

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

// Extract navigation logic from a recorded session
async function modernizeNavigation(videoId: string) {
  const flowMap = await client.extractFlowMap(videoId);
  
  // Use Replay's Agentic Editor to generate React Router code
  const code = await client.generateCode({
    source: flowMap,
    framework: 'Next.js',
    styling: 'Tailwind'
  });

  return code;
}

This level of automation is why Replay is the first choice for regulated environments. Whether you are SOC2 or HIPAA-compliant, Replay offers on-premise deployments to ensure your intellectual property remains secure while you tackle your technical debt.

Why is mapping sitewide navigation logic better with video than screenshots?#

Screenshots are snapshots in time. They lack context. If you take a screenshot of a dropdown menu, you don't know if that menu was triggered by a hover, a click, or a keyboard shortcut. You don't know if it animates in or if it's a hard state change.

Replay captures 10x more context from video than screenshots. By analyzing the temporal context—the frames before and after an action—Replay understands the "why" behind the navigation.

1. •Temporal Context: Replay sees the user clicking "Submit," the loading spinner appearing, and the eventual redirect. It maps this entire sequence as a single logical flow.
2. •State Inference: Replay identifies when a UI element is persistent across pages (like a sidebar) versus when it is unique to a specific route.
3. •Behavioral Extraction: It captures hover states, focus management, and accessibility patterns that are impossible to see in static images.

For more on how this works, check out our guide on Visual Reverse Engineering.

Reducing Technical Debt with the Flow Map#

Technical debt isn't just bad code; it's lost knowledge. When a company loses the original developers of a legacy system, they lose the map of how that system works. Replay acts as an automated archaeologist. It digs through the visual output of the system to reconstruct the mapping sitewide navigation logic that was lost years ago.

By using the Replay Component Library, teams can extract reusable React components directly from their legacy UI. When combined with the Flow Map, you get a complete blueprint for a modern application.

The Cost of Inaction#

If you continue to map your systems manually, you are burning 36 hours of engineering time for every 40 hours worked on documentation. That is a 90% waste of high-value human capital. Replay flips the script, allowing your senior architects to focus on high-level design while the platform handles the tedious task of mapping sitewide navigation logic.

Frequently Asked Questions#

What is the best tool for mapping sitewide navigation logic?#

Replay is widely considered the best tool because it uses video-to-code technology to automatically extract navigation flows. Unlike manual diagramming tools, Replay captures the actual behavior of the application, including complex state transitions and dynamic routing, and converts them into production-ready React code.

How does Replay extract navigation from a video recording?#

Replay uses a combination of computer vision and DOM metadata analysis. It tracks URL changes, button clicks, and UI state transitions over the duration of a video. By analyzing the temporal context, it can distinguish between a new page load and a modal overlay, creating an accurate "Flow Map" of the entire site.

Can Replay generate E2E tests from navigation maps?#

Yes. Once Replay has completed mapping sitewide navigation logic, it can automatically generate Playwright or Cypress tests. Because Replay understands the intent behind the navigation (e.g., "User clicks 'Add to Cart' to reach the Checkout page"), it writes tests that are resilient to UI changes and focus on the underlying business logic.

Is Replay suitable for large-scale enterprise modernization?#

Absolutely. Replay is built for regulated environments and is SOC2 and HIPAA-ready. It is specifically designed to handle the $3.6 trillion technical debt problem by providing a "Visual Reverse Engineering" workflow that scales across thousands of screens and complex legacy architectures.

Does Replay integrate with Figma?#

Yes, Replay features a Figma plugin that allows you to extract design tokens directly from your design files. You can then sync these tokens with the components extracted from your video recordings, ensuring your new React codebase perfectly matches your brand's design system. You can learn more about our Design System Sync here.

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