Getting Reactive with Vue.js: Exploring the Composition API

Vue.js, one of the most popular JavaScript frameworks, is known for its simplicity and power. With the introduction of the Composition API in Vue.js 3, developers have gained more flexibility and control over their code organization. This article explores the Composition API and how it enhances reactivity and code management in Vue.js applications.

The Composition API: An Overview

The Composition API is a new and optional way of writing and organizing Vue.js components. It’s an additive feature to Vue.js and doesn’t replace the existing Options API, but rather provides a set of additive, function-based APIs allowing flexible composition of component logic.

Key Features of the Composition API

1. Enhanced Logic Reuse and Organization

In larger applications, the Options API can lead to code that’s difficult to maintain and understand. The Composition API helps mitigate this by making it easier to reuse and organize logic in your components.

2. Better TypeScript Support

With the Composition API, you’ll benefit from improved TypeScript inference, which means you won’t need to add extra type annotations as often.

3. Clearer Source Code

Because you can split your component logic into separate functions, your source code can become more self-describing. This results in cleaner, more readable code.

Harnessing the Power of the Composition API

1. Basic Usage

The setup method is a new component option where you can use the Composition API. This method serves as the entry point for using the Composition API inside components.

2. Reactive Variables with ref

To create a reactive variable, you can use the ref function. A ‘ref’ is a value that Vue.js can track. When it changes, Vue knows to re-render the components that depend on it.

3. Reactive Objects with reactive

To create a reactive object, you can use the reactive function. This works similarly to ref, but is used for making objects reactive.

4. Computing and Watching

The computed and watch functions in the Composition API work the same as their counterparts in the Options API. They allow you to create computed properties and watch reactive data, respectively.


The Composition API in Vue.js is a powerful addition that offers a new way to structure your Vue applications. By enabling better logic reuse and organization, improved TypeScript support, and clearer source code, it helps make your Vue applications more maintainable and easier to understand. While it might take some getting used to, the Composition API is a significant step forward for Vue.js and a game-changer for Vue developers.