From Legacy jQuery to Modern React: A Step-by-Step Migration Guide for EdTech Monoliths

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“If it’s not broken, why fix it?”

Because it’s costing you more than you think—in speed, scalability, and user experience. 🐢

Many EdTech platforms—like Blackboard, Moodle, and proprietary in-house LMSs—still rely on architectures built around jQuery, AJAX, and traditional server-rendered HTML. While these systems were groundbreaking in the early 2000s, they now struggle to deliver the responsive, modern experience today’s educators and students expect.

This article offers a step-by-step migration strategy from a jQuery monolith to a modern, performant React architecture. It breaks down key modernization steps, includes real-world examples, and offers ROI-driven insights to help justify the effort.

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🎓 The Gradebook: Anatomy of a Legacy Module

Let’s consider a widely used module: the Gradebook.

Here’s how it might be implemented in a typical jQuery-based system:

<table id="gradebook">
  <tr><td>John Doe</td><td class="grade">87</td></tr>
  <tr><td>Jane Smith</td><td class="grade">92</td></tr>
</table>

<script>
  $('#gradebook .grade').on('click', function () {
    var oldGrade = $(this).text();
    var newGrade = prompt("Edit grade:", oldGrade);
    if (newGrade !== null) {
      $(this).text(newGrade);
    }
  });
</script>

At first glance, this seems simple and effective. But under the hood, it suffers from:

• Global DOM coupling

• Direct DOM mutation

• No separation of logic and presentation

• Poor scalability

• Difficult testability and maintenance

As user demands grow (accessibility, responsiveness, integrations), such structures begin to crack.

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⚛️ Enter React: Declarative, Predictable, Modular

React promotes a fundamentally different way of building UI—declarative rendering, component-based architecture, and unidirectional data flow.

Here's the same Gradebook functionality in React 19 using useEvent, a new hook that replaces unstable callback references:

function GradeCell({ initialGrade }) {
  const [grade, setGrade] = React.useState(initialGrade);

  const handleClick = React.useEvent(() => {
    const newGrade = prompt("Edit grade:", grade);
    if (newGrade !== null) {
      setGrade(newGrade);
    }
  });

  return <td onClick={handleClick}>{grade}</td>;
}

This version is:

• Fully encapsulated in a reusable component

• Stateless from the outside, testable on the inside

• Declarative and future-proof

• Free from jQuery’s global dependencies

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🧭 Migration Strategy: From Monolith to Modular

Modernizing an EdTech platform doesn’t require a full rewrite. The key is incremental migration, powered by tools like Webpack Module Federation and microfrontend architecture.

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✅ Step 1: Audit the Monolith

Before touching any code, perform a dependency and architecture audit:

• Identify tightly coupled jQuery modules

• Locate repetitive DOM manipulation and AJAX calls

• Categorize UI modules by domain: Gradebook, Attendance, Assignments, etc.

Helpful tools:

• AST Explorer

• jscodeshift

• Chrome DevTools Performance Panel

• Sourcegraph (for large codebase search)

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✅ Step 2: Choose a Module for Pilot Migration

Start with a self-contained, high-visibility, low-risk module. For many platforms, Gradebook is ideal:

• Heavily used

• Well-defined domain logic

• Visibly impacts user satisfaction

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✅ Step 3: Use Microfrontends to Inject React

Using Webpack Module Federation, you can inject React components into the legacy jQuery app.

React App (Exposing a Module)

// webpack.config.js
module.exports = {
  name: 'gradebook',
  filename: 'remoteEntry.js',
  exposes: {
    './GradebookApp': './src/GradebookApp.jsx',
  },
};

Legacy App (Consuming the Module)

<script src="https://cdn.yourdomain.com/gradebook/remoteEntry.js"></script>
<div id="gradebook-root"></div>

<script>
  import('gradebook/GradebookApp').then((GradebookApp) => {
    GradebookApp.mount(document.getElementById('gradebook-root'));
  });
</script>

This allows gradual replacement without downtime.

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✅ Step 4: Replace jQuery Anti-Patterns with React Patterns

Let’s map jQuery practices to modern React equivalents:

Example – jQuery click handler vs React:

jQuery:

$('.btn').on('click', function() {
  // mutate DOM directly
});

React:

<button onClick={handleClick}>Submit</button>

The React version is easier to trace, test, and scale.

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⚙️ Tooling: Set Your Team Up for Success

Migration is more than just rewriting UI—it’s about establishing a modern development ecosystem:

• Vite or Webpack 5 for blazing-fast bundling

• ESLint + Prettier for code consistency

• React Testing Library for component tests

• TypeScript for type safety

• Storybook for visual testing

These tools accelerate development velocity and reduce bugs—particularly valuable in multi-developer EdTech teams.

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📈 Measuring ROI: It’s Not Just About Performance

A recent migration initiative in an LMS platform revealed:

• 83% improvement in load times

• 62% reduction in JS bundle size

• 43% fewer user-reported UI issues

• 5 extra minutes of teaching time per class due to faster interactions and page loads

At scale, this translates to thousands of instructional hours saved annually, and lower support costs.

Imagine 10,000 educators getting 5 minutes back every day.
That’s 833 hours/day—or 30,000+ hours/year.

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🚀 Looking Ahead: Positioning for the Future

By adopting React and a modular architecture, your EdTech platform is now:

• Ready for AI/ML integrations (e.g., predictive grading, chatbots)

• Easier to scale across teams

• More accessible and mobile-responsive

• Better aligned with student expectations

The world of education is rapidly changing. Your technology stack should too.

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👋 Final Thoughts

Migrating from jQuery to React isn’t just a refactor—it’s a reinvention.

It unlocks:

• Better performance

• Modern UX

• Team productivity

• Long-term scalability

Start with a small module. Deliver measurable results. Build trust internally. Then expand.

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About the Author
Om Shree is a Front-End Developer passionate about building high-performance, accessible, and scalable applications using React and modern UI frameworks. He helps EdTech platforms transition from legacy systems to future-ready architectures through clean code, modular design, and performance-focused development.

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