How to Build a Scalable To-Do App with React and Node.js: A Practical Guide

Building software is easy. Building software that scales and actually solves user problems is the hard part. In this tutorial, we’ll walk through creating a simple To-Do App using React for the frontend and Node.js + Express for the backend — a real-world approach, with scalable architecture tips included.

No fluff, no hype — just actionable lessons you can implement.

Why Planning Matters

Even a simple To-Do App can get messy without proper planning:

• Poor state management → components break
• Backend without API structure → scaling issues
• Database without indexes → slow queries

Before coding, define:

• Data flow – How tasks move from frontend to backend
• Component structure – Keep UI modular
• API design – CRUD operations for tasks
• Scalability considerations – Prepare for growth

Planning saves headaches later.

Project Setup

We’ll use:

• Frontend: React (functional components + hooks)
• Backend: Node.js + Express
• Database: MongoDB
• Other tools: Axios for API calls, Nodemon for backend, Create React App

Folder Structure

todo-app/
├── backend/
│   ├── index.js
│   ├── routes/
│   └── models/
└── frontend/
    ├── src/
    │   ├── components/
    │   ├── App.js
    │   └── index.js

Keeping frontend and backend separate ensures scalability.

Frontend: React Example

TaskComponent.js

import React from 'react';

const TaskComponent = ({ task, onDelete }) => {
  return (
    <div className="task">
      <p>{task.title}</p>
      <button onClick={() => onDelete(task._id)}>Delete</button>
    </div>
  );
};

export default TaskComponent;

App.js

import React, { useState, useEffect } from 'react';
import TaskComponent from './components/TaskComponent';
import axios from 'axios';

function App() {
  const [tasks, setTasks] = useState([]);

  useEffect(() => {
    axios.get('http://localhost:5000/tasks')
      .then(res => setTasks(res.data))
      .catch(err => console.error(err));
  }, []);

  const deleteTask = id => {
    axios.delete(`http://localhost:5000/tasks/${id}`)
      .then(() => setTasks(tasks.filter(task => task._id !== id)));
  };

  return (
    <div>
      {tasks.map(task => (
        <TaskComponent key={task._id} task={task} onDelete={deleteTask} />
      ))}
    </div>
  );
}

export default App;

Backend: Node.js + Express Example

index.js

const express = require('express');
const mongoose = require('mongoose');
const cors = require('cors');
const Task = require('./models/Task');

const app = express();
app.use(cors());
app.use(express.json());

mongoose.connect('mongodb://localhost:27017/todo-app', {
  useNewUrlParser: true,
  useUnifiedTopology: true,
});

app.get('/tasks', async (req, res) => {
  const tasks = await Task.find();
  res.json(tasks);
});

app.post('/tasks', async (req, res) => {
  const newTask = new Task(req.body);
  await newTask.save();
  res.json(newTask);
});

app.delete('/tasks/:id', async (req, res) => {
  await Task.findByIdAndDelete(req.params.id);
  res.json({ message: 'Task deleted' });
});

app.listen(5000, () => console.log('Server running on port 5000'));
`
**Task Model**
`const mongoose = require('mongoose');

const TaskSchema = new mongoose.Schema({
  title: {
    type: String,
    required: true,
  },
});

module.exports = mongoose.model('Task', TaskSchema);

Scaling Tips

Even a simple To-Do App can be prepared for growth:

• Database indexing → faster queries
• Modular API routes → easy to expand
• Frontend component reusability → fewer bugs
• Use environment variables → secure credentials

At Decipher Zone, we implement similar scalable patterns for client projects, ensuring apps grow without breaking under load.

Lessons Learned

• Plan before coding: Architecture matters
• Keep frontend and backend modular: Easier maintenance
• Test iteratively: Early feedback prevents wasted effort
• Focus on user experience: Simple, intuitive UI wins

Even small projects benefit from thoughtful planning — it prevents wasted hours and improves maintainability.