From Lotus Notes to React: A Modernization Path for 90s Era Document Management

Lotus Notes is the "final boss" of enterprise technical debt. For thirty years, it served as the backbone of document management, workflow automation, and shadow IT, creating a sprawling ecosystem of proprietary

files that are nearly impossible to untangle. Today, these systems represent a massive operational risk: the developers who built them are retired, the infrastructure is a security liability, and the business logic is trapped in a black box.

The traditional response—a multi-year "Big Bang" rewrite—is a suicide mission. Statistics show that 70% of legacy rewrites fail or significantly exceed their timelines. When you're moving from Lotus Notes to a modern React-based architecture, you aren't just changing languages; you're attempting to perform archaeology on undocumented workflows while the business is still running.

TL;DR: Modernizing Lotus Notes doesn't require manual code archaeology; using Visual Reverse Engineering with Replay allows teams to extract business logic and UI components directly from user workflows, reducing migration timelines from years to weeks.

The Architecture of a Dead End: Why Lotus Notes Resists Modernization#

Lotus Notes was revolutionary because it tightly coupled data, logic, and UI. In 1995, this was a feature. In 2024, it is a catastrophic hurdle. Unlike modern web apps where the frontend and backend are decoupled via APIs, a Lotus Notes application is a monolithic entity where the "Form" is both the UI and the data schema.

The Documentation Gap#

67% of legacy systems lack any form of current documentation. In the context of Lotus Notes, the documentation usually exists only in the minds of employees who are five years into retirement. When you decide to move from Lotus Notes to React, your first hurdle isn't writing code—it's figuring out what the current code actually does.

The $3.6 Trillion Problem#

Global technical debt has ballooned to $3.6 trillion. Every hour your team spends trying to decode LotusScript or @Formula language is an hour stolen from innovation. Manual extraction of a single complex screen typically takes 40 hours of developer time. With Replay, that same extraction is compressed into 4 hours.

The Three Paths to Modernization#

When an Enterprise Architect looks at a legacy document management system, they generally see three paths. Only one of them is sustainable.

1. The Big Bang Rewrite#

You attempt to document everything, write a massive PRD, and build a new system from scratch.

• •Timeline: 18–24 months.
• •Risk: High. Usually results in "feature parity" arguments and 70% failure rates.
• •Cost: $$$$

2. The Strangler Fig Pattern#

You wrap the legacy system in a new interface and slowly migrate services.

• •Timeline: 12–18 months.
• •Risk: Medium. Often leads to "Frankenstein" architectures where the legacy system never truly dies.
• •Cost: $$$

3. Visual Reverse Engineering (The Replay Way)#

You record real user workflows in the legacy system. Replay's AI suite analyzes the video and interaction data to generate documented React components, API contracts, and E2E tests.

• •Timeline: 2–8 weeks.
• •Risk: Low. You are building based on the actual source of truth: how the software is used.
• •Cost: $

💰 ROI Insight: Companies using Replay see an average of 70% time savings on modernization projects. By automating the extraction of UI and logic, a project that would have taken two years can be completed in a single quarter.

Step-by-Step: Moving From Lotus Notes to React with Replay#

To move from Lotus Notes effectively, you must treat the legacy application as a black box that emits signals. Replay captures these signals and translates them into modern code.

Step 1: Workflow Recording#

Instead of reading 20-year-old LotusScript, have a power user perform a standard document approval workflow. Replay records the screen, the DOM interactions (if using Domino Web Access), and the network calls. This becomes your "Source of Truth."

Step 2: Component Extraction#

Replay’s Blueprints editor identifies recurring UI patterns. In Lotus Notes, this might be a "View" (a complex data grid) or a "Form" (a document editor). Replay generates a clean React component that mirrors the legacy functionality but uses modern best practices.

typescript
// Example: Generated React component from a Lotus Notes "Document View"
// Extracted via Replay Blueprints
import React, { useState, useEffect } from 'react';
import { DataGrid, GridColDef } from '@mui/x-charts'; // Or your Design System
import { fetchLegacyDocuments } from '../api/documentService';

interface LotusDocument {
  id: string;
  subject: string;
  author: string;
  createdDate: string;
  status: 'Draft' | 'Pending' | 'Approved';
}

export const DocumentManagementDashboard: React.FC = () => {
  const [docs, setDocs] = useState<LotusDocument[]>([]);

  useEffect(() => {
    // Logic preserved from legacy workflow analysis
    fetchLegacyDocuments().then(data => setDocs(data));
  }, []);

  const columns: GridColDef[] = [
    { field: 'subject', headerName: 'Subject', width: 200 },
    { field: 'author', headerName: 'Author', width: 150 },
    { field: 'status', headerName: 'Status', width: 120 },
  ];

  return (
    <div className="p-6 bg-slate-50 min-h-screen">
      <h1 className="text-2xl font-bold mb-4">Document Management</h1>
      <DataGrid rows={docs} columns={columns} checkboxSelection />
    </div>
  );
};

Step 3: Logic and API Contract Generation#

Lotus Notes often hides critical business logic in "Input Validation" or "PostSave" events. Replay identifies these transitions during the recording and generates an API contract that your new backend must fulfill.

json
{
  "contractName": "DocumentApprovalWorkflow",
  "endpoint": "/api/v1/documents/approve",
  "method": "POST",
  "requiredFields": [
    "docId",
    "approverLevel",
    "comments"
  ],
  "validationLogic": "If approverLevel < 2, set status to 'ManagerReview'; else 'FinalApproval'"
}

⚠️ Warning: Do not attempt to migrate 100% of the data on day one. Focus on migrating the functionality first using a "Read-Only" bridge to the legacy NSF data, then migrate the storage layer once the React frontend is stable.

Solving the "Archaeology" Problem#

The hardest part of moving from Lotus Notes is the "Hidden Logic" problem. Over decades, developers added "hidden" fields that trigger specific workflows. Manual auditors miss these 9 times out of 10.

Replay’s AI Automation Suite performs a technical debt audit by comparing the recorded visual workflow against the underlying code execution. If a user clicks "Approve" and three hidden fields change, Replay flags this as a required business logic rule in the generated Blueprint.

From Black Box to Documented Codebase#

By the end of the extraction process, Replay provides:

1. •A Library: A React-based design system that matches your corporate standards but functions like the legacy tool.
2. •Flows: Visual maps of how data moves through the application.
3. •E2E Tests: Automatically generated Playwright or Cypress tests based on the recorded user video.

💡 Pro Tip: Use the "Replay Library" feature to ensure your new React components are reusable across multiple migrated Lotus Notes databases. This prevents the creation of new silos during the modernization process.

Security and Compliance in Regulated Industries#

Many Lotus Notes systems still exist because they are in highly regulated sectors like Financial Services, Healthcare, or Government. The fear is that a rewrite will break compliance (HIPAA, SOC2).

Replay is built for these environments. It offers:

• •On-Premise Deployment: Your legacy data and recordings never leave your network.
• •PII Masking: Automatically redacts sensitive information during the recording and extraction process.
• •Audit Trails: Every component generated by Replay is linked back to the original recording, providing a clear chain of evidence for auditors.

The Cost of Inaction#

Every month you stay on Lotus Notes, you pay a "Legacy Tax."

• •Talent Drain: High-performing engineers don't want to work on Domino servers.
• •Integration Friction: Modern SaaS tools cannot easily talk to
  text

  .nsf
  files.
• •Security Vulnerabilities: Legacy platforms are increasingly difficult to patch against modern exploits.

The average enterprise rewrite timeline is 18 months. If you start a manual rewrite today, you will likely still be debugging it in two years. If you use Replay, you could have your first set of React components ready for staging by the end of next week.

Frequently Asked Questions#

How long does legacy extraction take?#

For a standard document management module, the recording takes minutes. The AI-assisted extraction and generation of React components typically take 4 to 8 hours per complex screen. A full application migration can often be completed in 2 to 8 weeks, depending on the number of unique workflows.

What about business logic preservation?#

Replay doesn't just copy the UI; it observes state changes. By recording the inputs and outputs of the legacy system, Replay creates a "functional twin" of the business logic. This logic is then documented in the Blueprints editor, where architects can review and refine it before it is exported as TypeScript.

Does Replay require access to the Lotus Notes source code?#

No. Replay uses Visual Reverse Engineering. It treats the application as a runtime environment. While having the source code can provide additional context, Replay’s primary value is extracting what is actually happening on the screen and in the network layer, which is often more accurate than stale source code.

Can Replay handle complex Lotus Notes "Views"?#

Yes. Lotus Notes Views are essentially complex, hierarchical data tables. Replay identifies these patterns and maps them to modern React components like TanStack Table or AG Grid, preserving the sorting, filtering, and categorization logic.

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