What is Mobx?

MobX is a state management solution, primarily used in JavaScript applications. It is renowned for its simplicity and scalability, making it a popular choice among developers. It facilitates the management of application state through observable state variables, computed values, and actions.

Understanding the Basics of MobX

MobX operates on a few core principles that make it unique among state management solutions. The first of these principles is the concept of observable state variables. These are variables that MobX tracks for changes. When changes occur, MobX ensures that all computations and side effects that depend on these variables are updated.

The second principle is the use of computed values. Computed values are values that are derived from the state. They are updated automatically when the state changes, ensuring that your application always has the most up-to-date data.

The third principle is the use of actions. Actions are functions that modify the state. They are the only way to change the state in a MobX application, ensuring that all state changes are predictable and traceable.

Advantages of Using MobX

Simple and Intuitive

MobX's simplicity is one of its most significant advantages. Its API is minimalistic, making it easy to learn and use. Furthermore, it doesn't impose a strict architecture on your application, giving you the freedom to structure your code as you see fit.

Another aspect of MobX's simplicity is its automatic tracking of dependencies. This means that you don't have to manually keep track of which parts of your application depend on which state variables. MobX handles this for you, ensuring that your application always reacts appropriately to state changes.

Efficient and Scalable

MobX is also highly efficient. It only updates the parts of your application that need to be updated when the state changes. This means that it doesn't waste resources updating parts of your application that aren't affected by a state change.

Furthermore, MobX is highly scalable. It works well for both small and large applications, making it a versatile choice for any project.

Getting Started with MobX


To get started with MobX, you first need to install it. You can do this using npm, the Node.js package manager. The command to install MobX is as follows:

npm install mobx --save

Once MobX is installed, you can import it into your JavaScript files using the import statement:

import { observable, computed, action } from 'mobx';

Creating an Observable State

Creating an observable state in MobX is straightforward. You simply use the observable decorator provided by MobX. Here's an example:

@observable count = 0;

In this example, count is an observable state variable. Any part of your application that depends on count will be updated automatically when count changes.

Creating Computed Values

Computed values in MobX are created using the computed decorator. Here's an example:

@computed get doubleCount() {
 return this.count * 2;

In this example, doubleCount is a computed value that is derived from the count state variable. It will be updated automatically whenever count changes.

Creating Actions

Actions in MobX are created using the action decorator. Here's an example:

@action incrementCount() {

In this example, incrementCount is an action that modifies the count state variable. It is the only way to change count in this application.


MobX is a powerful state management solution that offers simplicity, efficiency, and scalability. Its core principles of observable state variables, computed values, and actions make it a versatile tool for managing application state. Whether you're working on a small or large project, MobX is a great choice for state management.

Moropo Team
Dec 19, 2023

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