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February 19, 2026 min readsemantic state mapping using

Semantic State Mapping: Using Visual Evidence to Document 500+ Hidden Component Transitions

R
Replay Team
Developer Advocates

Semantic State Mapping: Using Visual Evidence to Document 500+ Hidden Component Transitions

Legacy systems are not static repositories of code; they are archaeological sites of undocumented intent. When an enterprise attempts to modernize a 15-year-old insurance portal or a complex banking dashboard, they aren't just fighting outdated syntax—they are fighting the "ghost in the machine." These systems often contain hundreds of undocumented state transitions where a button click triggers a cascade of visual changes that no living developer fully understands.

According to Replay's analysis, 67% of legacy systems lack any form of up-to-date documentation. This "documentation debt" is a primary driver of the $3.6 trillion global technical debt currently paralyzing enterprise innovation. When you can't see the logic, you can't migrate the logic. This is where semantic state mapping using visual evidence transforms a multi-year nightmare into a streamlined architectural exercise.

TL;DR: Manual reverse engineering of legacy UI states takes approximately 40 hours per screen and has a 70% failure rate in large enterprises. Semantic state mapping using Replay’s visual reverse engineering platform automates the discovery of hidden component transitions, reducing modernization timelines from 18 months to mere weeks by converting video recordings directly into documented React code and Design Systems.


The Crisis of Undocumented State Transitions#

The average enterprise rewrite timeline stretches to 18 months, yet 70% of these projects either fail or significantly exceed their budgets. Why? Because developers spend 80% of their time performing "forensic engineering"—manually clicking through old UIs, taking screenshots, and trying to guess the underlying conditional logic.

Video-to-code is the process of capturing these real-world user interactions and programmatically translating the visual changes into functional, documented code structures.

When dealing with 500+ hidden transitions—think of nested modals, multi-step forms with conditional validation, and dynamic data tables—manual mapping is impossible. Industry experts recommend moving away from manual "discovery phases" and toward automated visual evidence gathering.

The Cost of Manual Discovery vs. Replay#

MetricManual Reverse EngineeringSemantic State Mapping (Replay)
Time Per Screen40 Hours4 Hours
Documentation Accuracy45-60% (Human Error)99% (Visual Evidence)
Average Project Timeline18-24 Months4-8 Weeks
Cost Per Component$4,000 - $6,000$400 - $600
Tech Debt GeneratedHigh (Manual Guesswork)Low (Clean React Output)

What is Semantic State Mapping Using Visual Evidence?#

Semantic state mapping using visual evidence is a methodology where an AI-driven engine analyzes video recordings of a legacy application to identify "semantic markers"—visual cues that represent a change in the application's underlying logic.

Instead of just seeing a "blue button turning grey," a semantic mapper identifies a

text
Transition: IDLE -> LOADING
. It recognizes that the appearance of a spinner and the disabling of a form field are not two separate events, but a single atomic state change.

Definition: Semantic State Mapping#

Semantic State Mapping is the architectural process of correlating visual UI changes (diffs) with logical state transitions (Finite State Machines) to recreate application behavior in a modern framework without access to the original source code.

By leveraging Replay, architects can record a single "Flow" of a user journey. The platform's AI Automation Suite then parses every frame, identifies the components involved, and maps the transitions. This eliminates the need for developers to write boilerplate state logic from scratch.


Implementing Semantic State Mapping Using Replay#

To document 500+ transitions, you need a deterministic way to capture "Visual Evidence." In a typical legacy modernization project, the "source of truth" isn't the messy COBOL or jQuery backend—it's the UI the user actually interacts with.

Step 1: Recording the Visual Evidence#

Using Replay, an analyst records a "Flow." This isn't just a screen recording; it's a metadata-rich capture of the DOM's visual state. As the user navigates a complex insurance claim form, Replay tracks every hover state, validation error, and modal trigger.

Step 2: Extracting the Component Library#

Before you can map states, you need the atoms. Replay's Library feature automatically clusters visual patterns into a unified Design System. If the legacy app has 50 different versions of a "Submit" button, Replay identifies the semantic "Submit Button" component and its variants.

Step 3: Mapping the Transitions#

This is where semantic state mapping using visual intelligence becomes critical. The platform analyzes the "Flow" and generates a state chart.

Consider the following legacy logic captured from a 2008-era ERP system. The original code might look like this mess of jQuery:

javascript
// Legacy Spaghetti Logic (Undocumented) $('#submit-btn').on('click', function() { $(this).addClass('is-loading'); $('.error-msg').hide(); $.ajax({ url: '/api/v1/save', success: function(data) { if(data.status === 'ok') { window.location.href = '/success'; } else { $('#error-container').show().text(data.message); $('#submit-btn').removeClass('is-loading'); } } }); });

When performing semantic state mapping using Replay, the platform ignores the messy jQuery and focuses on the visual outcome. It sees:

  1. State A (Initial): Button active, no errors.
  2. State B (Pending): Button shows spinner, input fields read-only.
  3. State C (Error): Red text appears, button returns to active.

Replay then generates clean, modern TypeScript/React code that represents this logic as a Finite State Machine (FSM).

typescript
// Modernized React Component generated by Replay import React, { useState } from 'react'; import { Button, Alert, TextField } from './ui-library'; type FormState = 'IDLE' | 'LOADING' | 'ERROR' | 'SUCCESS'; export const ClaimSubmission: React.FC = () => { const [status, setStatus] = useState<FormState>('IDLE'); const [error, setError] = useState<string | null>(null); const handleSubmit = async () => { setStatus('LOADING'); try { await saveClaim(); // Logic abstracted from Replay Flow setStatus('SUCCESS'); } catch (e) { setError(e.message); setStatus('ERROR'); } }; return ( <div> {status === 'ERROR' && <Alert type="error">{error}</Alert>} <TextField disabled={status === 'LOADING'} /> <Button loading={status === 'LOADING'} onClick={handleSubmit} > Submit Claim </Button> </div> ); };

Scaling to 500+ Transitions: The "Flows" Architecture#

Documenting five transitions is a task; documenting 500 is a strategy. In large-scale enterprise environments—especially in regulated sectors like Financial Services or Government—consistency is the highest priority.

According to Replay's analysis, manual documentation of 500 transitions would take roughly 20,000 man-hours. By semantic state mapping using automated visual evidence, this is reduced to roughly 2,000 hours, most of which is spent on architectural review rather than manual data entry.

The Replay Blueprint Workflow#

  1. Capture: Record all 500+ transitions across different user roles (Admin, User, Guest).
  2. Analyze: Use Replay's Blueprints to visualize the "Architecture of the App." This creates a node-based map of how screens connect.
  3. Standardize: Export the visual evidence into a standardized React Component Library.
  4. Verify: Use the "Visual Regression" tool in Replay to ensure the new React component behaves exactly like the legacy recording.

Architects often struggle with "edge cases"—those transitions that only happen once in a thousand sessions. Because Replay captures real user workflows, these edge cases are documented automatically. You are no longer building for the "happy path"; you are building for the actual path.

For more on how to structure these migrations, see our guide on Legacy Modernization Strategies.


Why Visual Evidence Trumps Source Code#

In many legacy modernization projects, the source code is a liability. It is filled with "dead code," workarounds for IE6, and business logic that is no longer relevant. If you simply "translate" the code, you translate the technical debt.

By performing semantic state mapping using visual evidence, you perform a "clean room" implementation. You are documenting what the user sees and needs, not what the old code does.

Key Advantages of the Replay Approach:#

  • SOC2 & HIPAA Compliance: Replay is built for regulated environments. You can modernize sensitive healthcare or financial systems on-premise without exposing data to the public cloud.
  • Design System Integrity: Instead of "eye-balling" the CSS, Replay extracts the exact tokens (colors, spacing, typography) from the recording. Learn how to build a design system from video here.
  • AI Automation Suite: The platform's AI doesn't just guess; it uses deterministic visual diffing to ensure that every state transition in the new React app matches the legacy system's behavior.

Technical Deep Dive: Mapping Complex Data Grids#

One of the hardest things to document is the state of a complex data grid. Sorting, filtering, pagination, and inline editing can create thousands of possible state combinations.

When semantic state mapping using Replay, the engine identifies the "Grid" as a complex component. It maps the visual change of a header click to a

text
SORT_CHANGE
event. It recognizes that the "loading skeleton" that appears for 200ms is a transition state.

typescript
// Replay-generated DataGrid State Logic interface GridState { sortBy: string; order: 'asc' | 'desc'; page: number; view: 'list' | 'compact'; } const gridTransitions = { onHeaderClick: (column: string) => { // Replay identified this visual pattern across 14 different screens updateState({ sortBy: column, order: toggleOrder() }); }, onPageChange: (newPage: number) => { updateState({ page: newPage }); } };

This level of detail ensures that the modernized application doesn't just "look" like the old one—it "feels" like it, maintaining user productivity and reducing retraining costs.


The Path to 70% Time Savings#

The move from 18 months to weeks is not magic; it's the result of eliminating the "Discovery" bottleneck. In the traditional model, developers are the bottleneck. They must read, interpret, and rewrite.

With Replay, the bottleneck is removed.

  1. Product Owners record the workflows.
  2. Replay AI generates the documentation and base code.
  3. Architects review the "Flows" and "Blueprints."
  4. Developers refine the high-value business logic.

This shift allows teams to focus on innovation rather than archaeology. As technical debt continues to grow at an exponential rate, the ability to perform semantic state mapping using automated tools will become a requirement for any enterprise that wishes to remain competitive.


Frequently Asked Questions#

What is the difference between semantic state mapping and screen scraping?#

Screen scraping simply captures text or data from a UI. Semantic state mapping using visual evidence goes much deeper; it identifies the intent and logic behind visual changes. It doesn't just see a table; it understands the relationship between a filter input and the resulting data change, allowing it to generate functional React state logic rather than just static text.

How does Replay handle highly customized legacy components that don't follow modern standards?#

Replay’s AI Automation Suite is designed specifically for "non-standard" UIs found in legacy environments. It uses visual pattern recognition to cluster similar-looking elements into components, even if the underlying HTML is a mess of

text
<div>
and
text
<table>
tags. It then maps the transitions based on visual diffs, ensuring that the behavior is captured regardless of how poorly the original code was written.

Can Replay be used in secure, air-gapped, or highly regulated environments?#

Yes. Replay is built for enterprise-grade security. It is SOC2 compliant and HIPAA-ready. For organizations with strict data residency requirements, such as Government or Financial Services, Replay offers on-premise deployment options, ensuring that your "visual evidence" and source code never leave your secure perimeter.

Does the generated React code require significant refactoring?#

Replay generates "clean-room" React code and TypeScript definitions. While developers will still need to hook up the actual API endpoints (as Replay captures the visual side of the transition), the UI logic, component structure, and state transitions are 90% production-ready. This is what leads to the 70% average time savings in modernization projects.


Ready to modernize without rewriting? Book a pilot with Replay and see how visual reverse engineering can transform your legacy systems into modern React applications in weeks, not years.

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