Article posted Thu Mar 09 2023

JavaScript: RxJS, Lodash and JavaScript Libraries

Numerous libraries and frameworks exist in the field of web development, designed to assist developers in creating more efficient, robust, and easily maintainable code. Among the popular JavaScript libraries in the ecosystem are RxJS and Lodash, each serving unique purposes and catering to different use cases. This article aims to delve into these libraries and other libraries similar to them, examining their features, providing code examples, and demonstrating their specific use cases.


RxJS is a powerful library for reactive programming using Observables. Observables are a way to represent and manage asynchronous data streams, making it easier to write code that reacts to changes in data. RxJS provides a rich set of operators and functions to help developers manipulate and transform data streams. Here's an example of how RxJS can be used to debounce user input:

import { fromEvent } from 'rxjs';
import { debounceTime, map } from 'rxjs/operators';

const input = document.getElementById('input');

fromEvent(input, 'input')
map(event =>
.subscribe(value => console.log(value));

In this example, we use the fromEvent operator to create an Observable that emits events from the input element. We then use the debounceTime operator to debounce the input by 1 second, and the map operator to transform the emitted events into their corresponding input values. Finally, we subscribe to the Observable and log the input value whenever it changes.


Lodash is a utility library that provides a wide range of helper functions to manipulate and work with data. It includes functions for common tasks such as iterating over arrays and objects, sorting, filtering, and transforming data. Here's an example of how Lodash can be used to sort an array of objects:

import _ from 'lodash';

const users = [
{ name: 'Alice', age: 32 },
{ name: 'Bob', age: 21 },
{ name: 'Charlie', age: 45 },

const sortedUsers = _.sortBy(users, ['age']);


In this example, we use the sortBy function from Lodash to sort the users array by age. We pass in an array of properties to sort by, which in this case is just age. The sortBy function returns a new sorted array, which we log to the console.

Other Examples

There are many other libraries of this type available in the JavaScript ecosystem, including Underscore.js, Ramda, and Moment.js. Underscore.js is similar to Lodash in that it provides utility functions for working with data, while Ramda is a functional programming library that emphasizes immutability and currying. Moment.js is a popular library for working with dates and times, providing a simple and flexible API for parsing, formatting, and manipulating dates.

Use Cases

These libraries can be used in a wide range of applications and scenarios, from small personal projects to large-scale enterprise applications. For example, RxJS can be used in reactive user interfaces to handle complex interactions, while Lodash can be used to manipulate data in APIs or data processing pipelines. Other libraries like Moment.js can be used in projects that require complex date and time handling, such as scheduling or analytics. The benefits of using these libraries include increased productivity, reduced development time, and improved code quality.


Libraries such as RxJS and Lodash provide developers with powerful tools to manipulate and transform data, manage asynchronous data streams, and work with complex data structures. These libraries can be used in a wide range of applications and scenarios, from small personal projects to large-scale enterprise applications, and can help developers write