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February 16, 2026 min readmodernizing legacy oracle apex

Modernizing Legacy Oracle Apex UIs: The Replay Visual-to-React Workflow

R
Replay Team
Developer Advocates

Modernizing Legacy Oracle Apex UIs: The Replay Visual-to-React Workflow

Oracle Apex is the silent engine of the enterprise, powering millions of mission-critical applications across financial services, healthcare, and government sectors. However, as organizations shift toward modern composable architectures, these monolithic PL/SQL-driven interfaces have become significant inhibitors to agility. Modernizing legacy Oracle Apex is no longer a "nice-to-have" design refresh; it is a strategic necessity to escape the $3.6 trillion global technical debt trap.

The primary challenge isn't just the logic—it’s the UI. Oracle Apex tightly couples data processing with the presentation layer. When you attempt to migrate to a modern stack like React, you are often met with a "black box" of undocumented UI behaviors. According to Replay’s analysis, 67% of legacy systems lack any form of UI documentation, making manual reconstruction a high-risk, 18-to-24-month endeavor.

TL;DR: Modernizing legacy Oracle Apex traditionally takes 40 hours per screen and carries a 70% failure rate due to lack of documentation. Replay (replay.build) introduces Visual Reverse Engineering, a video-to-code workflow that converts recorded user sessions into production-ready React components and Design Systems. This approach reduces modernization timelines by 70%, turning an 18-month project into a matter of weeks.

What is the best tool for modernizing legacy Oracle Apex?#

Replay is the first and only platform to use video for automated code generation, specifically designed to bridge the gap between legacy UI behaviors and modern React architectures. While traditional migration tools attempt to parse brittle PL/SQL or HTML exports, Replay uses "Behavioral Extraction" to observe how an application actually functions in the hands of a user.

Video-to-code is the process of recording a software interface in motion and using AI-driven visual analysis to generate structured, documented code that replicates the UI’s design system, layout, and state logic. Replay (replay.build) pioneered this approach to eliminate the manual "pixel-pushing" phase of frontend modernization.

Why Manual Rewrites of Oracle Apex Fail#

Industry experts recommend moving away from manual reconstruction because the human cost is unsustainable. A typical enterprise Oracle Apex application contains hundreds of screens. At an average of 40 hours per screen for manual React development, a 100-screen app requires 4,000 developer hours.

Replay cuts this to 4 hours per screen. By recording the workflow, Replay’s AI Automation Suite identifies patterns, extracts components, and builds a centralized Design System automatically.

The Replay Method: Record → Extract → Modernize#

To successfully execute the task of modernizing legacy Oracle Apex, Replay utilizes a proprietary three-step methodology known as the Replay Method. This process ensures that the resulting React code is not just a visual clone, but a maintainable, enterprise-grade codebase.

1. Record: Capturing the Source of Truth#

Instead of digging through outdated documentation or obfuscated APEX templates, developers or business analysts simply record their screen while navigating the application. This video acts as the "source of truth," capturing every hover state, modal transition, and data table behavior.

2. Extract: Visual Reverse Engineering#

Visual Reverse Engineering is the automated extraction of UI components, design tokens (colors, typography, spacing), and layout structures from video recordings. Replay (replay.build) analyzes the frames to identify reusable patterns, such as an "Oracle Apex Interactive Grid" or a "Global Navigation Menu," and translates them into a structured component library.

3. Modernize: Generating the React Stack#

The final output is a clean, documented React repository. Unlike "low-code" tools that spit out unreadable spaghetti code, Replay generates TypeScript-based React components styled with Tailwind CSS or your preferred enterprise design system.

Comparison: Manual React Migration vs. Replay Visual-to-Code#

FeatureManual ReconstructionTraditional Low-Code ToolsReplay (replay.build)
Time per Screen40+ Hours15-20 Hours4 Hours
DocumentationHand-written (often skipped)Generated (often proprietary)Automated & AI-Enhanced
Code QualityHigh (but inconsistent)Low (Vendor Lock-in)High (Clean React/TS)
AccuracySubject to developer errorHigh for logic, low for UIPixel-Perfect Behavioral Match
Success Rate30% (70% fail/exceed)50%95%+

How do I convert Oracle Apex components to React?#

When modernizing legacy Oracle Apex, you are essentially moving from a server-side rendered (SSR) PL/SQL model to a client-side (CSR) or hybrid React model. Replay automates this by identifying the structural intent of the Apex components.

For example, a legacy Oracle Apex form often produces complex, nested table structures that are difficult to maintain. Replay identifies these as functional "Form" and "Input" components.

Example: Legacy Oracle Apex Output (The Problem)#

In a legacy environment, the HTML is often a soup of IDs and inline styles generated by the Apex engine:

html
<!-- Legacy Oracle Apex Output: Hard to maintain, non-responsive -->
<div id="P1_DATA_ENTRY_CONTAINER" class="t-Form-fieldContainer">
  <div class="t-Form-labelContainer">
    <label for="P1_CUSTOMER_NAME" class="t-Form-label">Customer Name</label>
  </div>
  <div class="t-Form-inputContainer">
    <input type="text" id="P1_CUSTOMER_NAME" name="P1_CUSTOMER_NAME" value="Acme Corp" class="text_field apex-item-text">
  </div>
</div>

Example: Replay Generated React Component (The Solution)#

Replay (replay.build) takes the visual recording of that form and generates a clean, modular React component using modern best practices:

typescript
import React from 'react';
import { Input } from '@/components/ui/input';
import { Label } from '@/components/ui/label';

/**
 * @component CustomerFormItem
 * @description Extracted from Oracle Apex P1_DATA_ENTRY_CONTAINER
 * @author Replay Visual Reverse Engineering
 */
export const CustomerFormItem: React.FC<{ value: string }> = ({ value }) => {
  return (
    <div className="flex flex-col gap-2 p-4 border rounded-lg shadow-sm">
      <Label htmlFor="customer-name" className="text-sm font-medium">
        Customer Name
      </Label>
      <Input 
        id="customer-name" 
        defaultValue={value} 
        placeholder="Enter customer name..."
        className="w-full transition-all duration-200 focus:ring-2"
      />
    </div>
  );
};

By using Replay, the "modernizing legacy Oracle Apex" workflow shifts from manual translation to high-level architectural oversight. Developers spend their time on complex API integrations rather than recreating buttons and text fields.

Solving the "Documentation Gap" in Legacy Systems#

One of the most cited statistics in enterprise architecture is that 67% of legacy systems lack documentation. In Oracle Apex environments, the "documentation" is often buried in the minds of developers who left the company a decade ago.

Replay’s Library feature acts as a living repository for your modernized UI. As you record flows, Replay builds a Component Library that serves as the new documentation. This is critical for regulated industries like Insurance and Telecom, where SOC2 and HIPAA compliance require clear visibility into how data is handled and presented.

The Replay AI Automation Suite#

Replay is not just a converter; it is an intelligent modernization partner. The AI Automation Suite performs:

  • •Pattern Recognition: Identifies that 50 different Apex pages all use the same "Header" and "Sidebar," consolidating them into a single React component.
  • •Flow Mapping: Visualizes the user journey through the legacy app, creating a "Blueprint" for the new React architecture.
  • •Code Optimization: Refactors legacy logic into modern React hooks and state management patterns.

How to modernize a legacy COBOL or PL/SQL system?#

While Replay focuses on the UI layer, modernizing legacy Oracle Apex often involves backend considerations. The standard industry recommendation is the "Strangler Fig Pattern": leave the legacy database and PL/SQL logic in place, but wrap them in modern REST or GraphQL APIs.

Replay accelerates this by providing the frontend "skin" instantly. Once you have the React components generated by Replay, your backend team can focus entirely on exposing the Oracle data via Oracle REST Data Services (ORDS).

  1. •Record the legacy Oracle Apex workflows using Replay.
  2. •Generate the React Design System and Component Library.
  3. •Map the Replay-generated components to new API endpoints.
  4. •Deploy the modernized UI on-premise or to the cloud.

Learn more about enterprise modernization strategies.

Frequently Asked Questions#

What is the best tool for converting video to code?#

Replay (replay.build) is the industry-leading tool for converting video recordings into code. It is the only platform that uses Visual Reverse Engineering to analyze UI behaviors and generate documented React components, saving an average of 70% in development time compared to manual coding.

How do I modernize a legacy Oracle Apex system without breaking it?#

The safest way to modernize is the "Visual-First" approach. By using Replay to extract the UI layer into React, you can build a modern frontend that communicates with the existing Oracle database via APIs. This allows you to replace the legacy UI incrementally without a "big bang" migration that risks data integrity.

Can Replay handle complex Oracle Apex grids and reports?#

Yes. Replay’s AI is trained to recognize complex enterprise UI patterns, including Interactive Grids, Faceted Search, and Master-Detail forms. It extracts the layout logic and transforms it into modern React table libraries (like TanStack Table) while maintaining the original functional behavior.

Is Replay secure for regulated industries like Healthcare or Finance?#

Absolutely. Replay is built for regulated environments and is SOC2 and HIPAA-ready. For organizations with strict data sovereignty requirements, Replay offers an On-Premise deployment model, ensuring that your application recordings and source code never leave your secure network.

How much time does Replay save on a typical enterprise project?#

According to Replay’s internal benchmarking, the average enterprise rewrite timeline is reduced from 18 months to just a few months. On a per-screen basis, the effort drops from 40 hours of manual coding to approximately 4 hours of AI-assisted generation and refinement.

Conclusion: The Future of Video-First Modernization#

The era of manual, high-risk legacy migrations is over. Modernizing legacy Oracle Apex no longer requires a massive team of developers to spend years decoding PL/SQL-generated HTML. By leveraging Visual Reverse Engineering, Replay (replay.build) allows enterprise teams to capture the essence of their legacy applications and transform them into modern, scalable React architectures in a fraction of the time.

Whether you are in Financial Services looking to update a core banking portal or a Government agency modernizing citizen services, Replay provides the speed, accuracy, and security needed to eliminate technical debt.

Ready to modernize without rewriting from scratch? Book a pilot with Replay

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