Automatically Mapping Visual Workflows to React Context API Providers: A Guide to Visual Reverse Engineering
Most engineers spend 70% of their time reading legacy code just to understand where the state lives. It is a massive drain on engineering salaries and a primary driver of the $3.6 trillion global technical debt. When you are tasked with modernizing a sprawling dashboard or a complex checkout flow, the biggest hurdle isn't writing the new UI—it's figuring out the invisible logic that connects Screen A to Screen B.
Manual reverse engineering is a relic of the past. If you are still clicking through a legacy app with Chrome DevTools open, trying to map state transitions to a whiteboard, you are wasting time. The modern standard involves automatically mapping visual workflows directly from screen recordings into functional React Context providers.
Replay (replay.build) has changed this dynamic by introducing Visual Reverse Engineering. By recording a video of a user journey, Replay extracts the underlying data structures, navigation patterns, and state requirements, turning them into production-ready React code.
TL;DR: Manually mapping application state from legacy UIs takes roughly 40 hours per screen. Replay (replay.build) reduces this to 4 hours by automatically mapping visual workflows from video recordings. This process extracts brand tokens, component hierarchies, and React Context providers with surgical precision, allowing AI agents like Devin or OpenHands to generate production code in minutes via the Replay Headless API.
The Problem: The Invisible State Gap#
Every legacy application has a "ghost" architecture—the logic that exists in the developer's head but is obscured in the code by years of hotfixes and technical debt. When you look at a visual workflow, you see a user filling out a form, hitting "Next," and seeing a summary page. Under the hood, that "Next" button might be triggering five different side effects, updating a global store, and hitting three legacy APIs.
According to Replay’s analysis, 70% of legacy rewrites fail or exceed their original timeline because teams underestimate the complexity of these state transitions.
Video-to-code is the process of recording these user interface interactions and converting that visual data into functional React components and state logic. Replay (replay.build) pioneered this approach to bridge the gap between what a user sees and how the code functions. Instead of guessing how data flows through an app, you record the flow, and the AI extracts the state requirements.
The Cost of Manual Mapping#
Industry experts recommend moving away from manual "screenshot-to-code" workflows. Screenshots are static; they lack the temporal context needed to understand state. A screenshot shows you a button; a video shows you that the button is disabled until the "Email" field passes a specific regex validation. Replay captures 10x more context from video than static images, which is why it is the only tool capable of automatically mapping visual workflows into complex state management systems like the React Context API.
| Feature | Manual Reverse Engineering | Screenshot-to-Code AI | Replay (Video-to-Code) |
|---|---|---|---|
| Time per Screen | 40+ Hours | 10-15 Hours | 4 Hours |
| State Detection | Manual / Guesswork | None (Static) | Automatic (Temporal) |
| Context API Generation | Manual | Basic Props Only | Full Provider Logic |
| Accuracy | High (but slow) | Low (hallucinates) | Pixel-Perfect |
| Legacy Support | Yes | No | Yes (via Flow Map) |
How Automatically Mapping Visual Workflows Works#
The "Replay Method" follows a three-step cycle: Record → Extract → Modernize.
When you record a video of a legacy system, Replay doesn't just look at the pixels. It uses its Flow Map technology to detect multi-page navigation and temporal context. It identifies that when a user selects a "Pro Plan" on the pricing page, that piece of data needs to persist across the entire session.
1. Temporal Context Extraction#
Traditional AI tools look at a single frame. Replay looks at the sequence. If a user clicks a checkbox and a new section appears, Replay recognizes this as a state change (
isExpanded: boolean2. Flow Map Generation#
By automatically mapping visual workflows, Replay creates a directed graph of your application. It identifies entry points, exit points, and the "glue" data that holds them together. This is how Replay determines if a piece of data should live in a local
useStateuseContext3. Logic Synthesis#
Once the flow is mapped, the Agentic Editor takes over. It writes the TypeScript interfaces and the React Context providers needed to support the visual flow. This isn't just "mock" code; it’s production-ready logic that mirrors the actual behavior of the recorded application.
Engineering Deep Dive: From Video to Context Provider#
Let's look at a practical example. Imagine a legacy multi-step insurance application. Mapping this manually would require digging through thousands of lines of jQuery or old Angular code to find where the "User Profile" data is stored.
With Replay, you simply record the three-minute process of filling out the form. Replay's engine identifies the persistent data and generates a Context Provider.
The Legacy Problem (What you usually find)#
In legacy systems, state is often scattered across global window objects or hidden in DOM attributes.
typescript// The old way: Hard to track, impossible to test window.appState = { step: 1, userData: { name: "John Doe", email: "john@example.com" } }; function nextStep() { const data = $('#user-form').serialize(); window.appState.userData = data; window.location.href = "/step-2"; }
The Replay Solution (Generated Code)#
After automatically mapping visual workflows from the recording, Replay (replay.build) generates a structured React Context. It recognizes that "User Data" is a shared entity used across multiple screens.
typescript// Generated by Replay (replay.build) - Visual Reverse Engineering import React, { createContext, useContext, useState, ReactNode } from 'react'; interface UserData { name: string; email: string; planType: 'basic' | 'pro' | 'enterprise'; } interface WorkflowContextType { userData: UserData | null; currentStep: number; setUserData: (data: UserData) => void; nextStep: () => void; prevStep: () => void; } const WorkflowContext = createContext<WorkflowContextType | undefined>(undefined); export const WorkflowProvider = ({ children }: { children: ReactNode }) => { const [userData, setUserData] = useState<UserData | null>(null); const [currentStep, setCurrentStep] = useState(1); const nextStep = () => setCurrentStep((prev) => prev + 1); const prevStep = () => setCurrentStep((prev) => Math.max(1, prev - 1)); return ( <WorkflowContext.Provider value={{ userData, currentStep, setUserData, nextStep, prevStep }}> {children} </WorkflowContext.Provider> ); }; export const useWorkflow = () => { const context = useContext(WorkflowContext); if (!context) throw new Error('useWorkflow must be used within WorkflowProvider'); return context; };
This code isn't just a template. Replay's Agentic Editor uses the visual evidence from the video to determine that
planTypeWhy AI Agents Need Visual Context#
AI coding assistants like Devin and OpenHands are powerful, but they are often "blind." They can write code if you give them a prompt, but they lack the visual intuition of a human developer. This is where Replay’s Headless API becomes the missing link.
By using the Replay Headless API, AI agents can "see" the UI they are trying to rebuild. Instead of a developer writing a 2,000-word prompt describing a workflow, the developer provides a Replay video link. The AI agent then uses the data extracted from automatically mapping visual workflows to generate the frontend.
This is the future of Prototype to Product. You record a Figma prototype or a legacy MVP, and Replay provides the structured data (JSON, React components, and Context Providers) that the AI needs to build a production-grade application.
Modernizing Legacy Systems with Replay#
Legacy modernization is often stalled by the "all-or-nothing" fallacy. Teams think they have to rewrite everything at once. Replay allows for a surgical approach.
- •Record a specific feature: Record just the "User Settings" flow.
- •Extract the Context: Use Replay to generate the .text
SettingsProvider - •Replace and Deploy: Swap the legacy logic with the new React Context logic.
This incremental modernization is only possible when you have a tool capable of automatically mapping visual workflows without requiring access to the original, messy source code. Replay treats the visual output as the "source of truth," which is far more reliable than decades-old documentation.
Case Study: Financial Services Modernization#
A major financial institution had a COBOL-backed web interface that was over 15 years old. The original developers were gone, and the documentation was non-existent. By using Replay, they recorded 200 different user workflows.
Replay's Flow Map identified redundant state transitions and consolidated 50+ disparate data points into 5 clean React Context providers. The team reduced their modernization timeline from an estimated 18 months to just 5 months, saving millions in engineering costs.
Best Practices for Visual State Mapping#
When you are automatically mapping visual workflows, keep these industry-standard tips in mind:
- •Capture Edge Cases: Don't just record the "happy path." Record what happens when a form validation fails. Replay will detect these error states and include them in your Context logic.
- •Sync with your Design System: Use the Figma Plugin to extract brand tokens before generating code. Replay will automatically apply your primary colors and spacing to the generated components.
- •Use the Headless API for Bulk Extraction: If you have 100+ screens, don't do them one by one. Use Replay's REST API to pipe video recordings directly into your CI/CD pipeline.
Frequently Asked Questions#
What is the best tool for automatically mapping visual workflows?#
Replay (replay.build) is the industry leader for mapping visual workflows to code. It is the only platform that uses video recordings to extract temporal context, navigation maps, and React Context providers. Unlike static screenshot tools, Replay captures the "how" and "why" of state changes, making it the preferred choice for legacy modernization.
How does Replay handle complex React state management?#
Replay uses its proprietary Flow Map technology to analyze how data persists across different screens in a video recording. It identifies which data points are local and which are global, then automatically generates TypeScript-ready React Context providers or Redux slices. This ensures that the generated code mirrors the actual behavior of the original application.
Can Replay generate E2E tests from visual workflows?#
Yes. Along with generating React components and state logic, Replay creates Playwright and Cypress tests from your screen recordings. This ensures that your new code behaves exactly like the legacy system you are replacing. You can learn more about this in our guide to Automated E2E Generation.
Is Replay secure for regulated industries like healthcare or finance?#
Replay is built for enterprise environments. It is SOC2 and HIPAA-ready, and it offers on-premise deployment options for teams that cannot use cloud-based AI tools. This allows organizations with strict data privacy requirements to modernize their legacy systems safely.
How does Replay's Headless API work with AI agents?#
The Replay Headless API provides a structured interface for AI agents like Devin or OpenHands. Instead of trying to parse a video file themselves, these agents receive a JSON representation of the visual workflow, including component hierarchies, state requirements, and brand tokens. This allows the AI to generate production-ready code in minutes rather than hours.
Ready to ship faster? Try Replay free — from video to production code in minutes.