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February 10, 20269 min readprogress 4gl react

Progress 4GL to React: Modernizing Legacy Textile ERP Systems with Visual Context Extraction

R
Replay Team
Developer Advocates

The average textile ERP built on Progress 4GL contains over 5 million lines of code, 67% of which has no surviving documentation. For a $500M textile manufacturer, this isn't just technical debt; it’s a business existential threat. When your core inventory logic, dye-lot calculations, and loom scheduling are trapped in a Progress OpenEdge "black box," you aren't just running legacy software—you are running a risk that grows every time a senior developer nears retirement.

The traditional answer has been the "Big Bang" rewrite. But with 70% of legacy rewrites failing or exceeding their timelines, the industry is littered with $10M projects that were abandoned at the 24-month mark. The industry needs a new path for progress 4gl react modernization that doesn't rely on manual code archaeology.

TL;DR: Modernizing Progress 4GL to React using visual context extraction bypasses the need for manual code audits, reducing migration timelines from years to weeks by using recorded user workflows as the source of truth.

The Progress 4GL Deadlock in Textile Manufacturing#

Textile ERPs are uniquely complex. They manage multi-dimensional inventory (width, weight, color, composition), complex Units of Measure (UOM), and high-velocity supply chain movements. Most of these systems were built in the 1990s using Progress 4GL (now OpenEdge ABL). While the database remains robust, the UI/UX is a productivity killer, and the procedural logic is nearly impossible to port to modern microservices without breaking core business rules.

The primary friction point in a progress 4gl react migration is the "Documentation Gap." When 67% of systems lack documentation, architects spend 80% of their time just trying to understand what the current system actually does.

Why Manual Modernization Fails#

  1. •The Logic Trap: Progress 4GL often mixes UI logic with business logic in
    text
    .w
    and
    text
    .p
    files. Separating them manually is a recipe for regression.
  2. •The Talent Gap: Finding developers who understand both Progress ProDataSets and React functional components is like finding a needle in a haystack.
  3. •The Timeline Stretch: The average enterprise rewrite takes 18 months. In the fast-moving textile world, your requirements will change three times before you even ship the "New Inventory" module.
ApproachTimelineRiskCostDocumentation
Big Bang Rewrite18-24 monthsHigh (70% fail)$$$$Manual/Incomplete
Strangler Fig12-18 monthsMedium$$$Incremental
Replay (Visual Extraction)2-8 weeksLow$Automated/Live

The Future Isn't Rewriting—It's Understanding#

The core philosophy of Replay is that the future of modernization isn't rewriting from scratch; it's understanding what you already have. Instead of reading through millions of lines of Progress ABL code, Replay uses Visual Reverse Engineering.

By recording a real user performing a workflow—such as "Assigning a Dye Lot to a Production Order"—Replay captures the state, the data inputs, the API calls (or database triggers), and the UI hierarchy. It then converts this "video as a source of truth" into documented React components and TypeScript interfaces.

💰 ROI Insight: Manual screen migration typically takes 40 hours per screen. With Replay’s visual extraction, that is reduced to 4 hours per screen, representing a 90% reduction in labor costs.

Technical Deep Dive: From Progress 4GL to React Components#

When moving from a procedural Progress environment to a modern React stack, the biggest challenge is state management. Progress handles state via shared variables and temp-tables. In a progress 4gl react architecture, we must map these to React hooks and a centralized state (like Redux or TanStack Query).

Replay automates this by generating the "Skeleton" of the component based on the actual user interaction.

Example: Generated React Component for Textile Inventory#

Below is an example of what Replay extracts from a legacy Progress "Inventory Lookup" screen. It captures the business logic of the dye-lot validation that was previously hidden in a

text
.p
procedure.

typescript
// Generated by Replay Visual Extraction
// Source: inventory_maint.w (Progress OpenEdge)

import React, { useState, useEffect } from 'react';
import { TextField, Button, Alert } from '@mui/material';

interface InventoryItem {
  itemCode: string;
  dyeLot: string;
  availableYardage: number;
  uom: 'YARDS' | 'METERS';
}

export const DyeLotValidator: React.FC = () => {
  const [item, setItem] = useState<string>('');
  const [lot, setLot] = useState<string>('');
  const [error, setError] = useState<string | null>(null);

  // Logic extracted from Progress 'find-lot' trigger
  const validateLotAssignment = async () => {
    try {
      const response = await api.post('/v1/textile/validate-lot', { item, lot });
      if (!response.isValid) {
        setError("Dye lot mismatch for selected fabric weight.");
      }
    } catch (err) {
      setError("System error connecting to OpenEdge AppServer.");
    }
  };

  return (
    <div className="p-4 border rounded-lg shadow-sm">
      <h3 className="text-lg font-bold">Dye Lot Assignment</h3>
      <TextField 
        label="Item Code" 
        value={item} 
        onChange={(e) => setItem(e.target.value)} 
      />
      <TextField 
        label="Lot Number" 
        value={lot} 
        onChange={(e) => setLot(e.target.value)} 
      />
      <Button onClick={validateLotAssignment}>Validate & Assign</Button>
      {error && <Alert severity="error" className="mt-2">{error}</Alert>}
    </div>
  );
};

⚠️ Warning: Do not attempt to "lift and shift" Progress logic directly. Progress is event-driven and synchronous; React is functional and asynchronous. Use Replay to extract the intent of the logic, not just the syntax.

Step-by-Step: The Replay Modernization Workflow#

Modernizing a textile ERP requires a surgical approach. You cannot take the system offline. Here is how we execute a progress 4gl react migration using Replay.

Step 1: Visual Recording#

A subject matter expert (SME) logs into the legacy Progress system. They perform a specific business task—for example, "Creating a Bill of Lading." Replay records the screen, the DOM (or terminal character map), and the network traffic.

Step 2: Context Extraction#

Replay’s AI Automation Suite analyzes the recording. It identifies:

  • •Input fields and their validation rules.
  • •Data tables and their relationships.
  • •Hidden business logic (e.g., "If fabric type is 'Synthetic', add 5% to waste calculation").
  • •API surface area required to support this screen.

Step 3: Blueprint Generation#

The "Blueprint" is a technical audit of the screen. It maps the legacy Progress widgets to modern React components in your Design System (Library). If you don't have a design system, Replay generates one based on your brand guidelines.

Step 4: Code Export#

Replay exports production-ready React code, E2E tests (Cypress/Playwright), and API contracts (OpenAPI/Swagger).

yaml
# Generated API Contract for Progress Backend Bridge
openapi: 3.0.0
info:
  title: Textile ERP Modernization API
paths:
  /inventory/dye-lot/validate:
    post:
      summary: Validates dye lot against fabric specifications
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                item_id: {type: string}
                lot_id: {type: string}
      responses:
        '200':
          description: Validation result

Addressing the $3.6 Trillion Technical Debt Problem#

The global technical debt crisis is fueled by the fear of breaking "what works." In the textile and manufacturing sectors, the cost of a 15-minute outage on the production line can exceed $50,000. This is why VPs of Engineering are hesitant to touch Progress 4GL systems.

Replay mitigates this risk by providing a "Technical Debt Audit" before a single line of code is written. By visualizing the dependencies of your legacy system, you can prioritize which modules to move to React first based on business value rather than technical ease.

Key Features of Replay for Regulated Industries#

  • •SOC2 & HIPAA-Ready: Essential for healthcare textiles and government-contracted manufacturing.
  • •On-Premise Availability: Keep your proprietary manufacturing logic behind your firewall.
  • •Library (Design System): Ensure consistency across the new React modules so the "Inventory" screen looks and feels like the "Shipping" screen.
  • •Flows (Architecture): Map how data moves from your Progress database through your middleware to the React frontend.

💡 Pro Tip: Start your progress 4gl react journey with "Read-Only" screens. Migrating your Dashboards and Inquiry screens first provides immediate value to executives without risking core transactional integrity.

The Strangler Fig Pattern: A Safer Path#

We recommend the Strangler Fig pattern for Progress migrations. Instead of replacing the whole ERP, you "strangle" the old system by replacing individual screens with React components.

  1. •Proxy the Traffic: Use a modern gateway to route users to the new React screens for specific modules.
  2. •Visual Extraction: Use Replay to rapidly build the React version of the next module.
  3. •Bridge the Data: Use a Change Data Capture (CDC) tool or a REST wrapper around your Progress AppServer to keep data in sync.
  4. •Retire: Once the React module is stable, decommission the old Progress
    text
    .w
    files.

Frequently Asked Questions#

How does Replay handle Progress 4GL systems that aren't web-based (CHUI)?#

Replay's visual extraction technology is designed to interpret UI patterns regardless of the underlying rendering engine. For Character-Based User Interfaces (CHUI), Replay analyzes the terminal output and state transitions to map them to modern web inputs and data tables.

Can we preserve our custom business logic in the move to React?#

Yes. Replay extracts the logic flow. For example, if your Progress code has a specific calculation for "Shrinkage Allowance" based on fabric composition, Replay identifies that calculation during the recording and documents it in the generated TypeScript component or API contract, ensuring no "tribal knowledge" is lost.

How long does a typical Progress 4GL to React screen migration take?#

While a manual rewrite takes roughly 40 hours per screen (including discovery, design, coding, and testing), Replay users average 4 hours per screen. For a typical ERP module with 50 screens, this moves the timeline from 12 months to approximately 5 weeks.

Is the code generated by Replay "black box" code?#

No. Replay generates clean, human-readable TypeScript and React code that follows modern best practices (functional components, hooks, Tailwind CSS or Material UI). Your team owns the code entirely; there is no proprietary runtime required.

Does Replay require access to our Progress source code?#

No. Replay is a visual reverse engineering platform. It learns from the behavior of the application. While having source code helps for verification, Replay's primary "source of truth" is the recorded user workflow and the data it produces. This is ideal for companies that have lost the original source code or lack documentation.

Ready to modernize without rewriting? Book a pilot with Replay - see your legacy screen extracted live during the call.

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