Lit.js: A Fast and Lightweight Alternative to React
When it comes to choosing a frontend framework, developers have a multitude of options. While React remains one of the most popular choices, other frameworks are worth exploring. Lit.js, backed by Google, is a fast and lightweight alternative that’s gaining traction.
What is Lit.js?
Lit.js is a JavaScript framework that allows you to create modern web components using a tiny boilerplate footprint. Its core features include:
- LitElement: A convenient and versatile extension of the native HTMLElement
- Expressive and declarative templates: Easy definition of how a component should be rendered
- Reactive properties: Automatic re-rendering of components when a reactive property changes
- Scoped styles: Simple CSS selectors that don’t affect other contexts
- Support for Vanilla JavaScript, TypeScript, and ergonomics: Decorators and type declarations
New Features in Lit.js 0.7.0
The latest version of Lit.js introduces several significant changes, including:
- Smaller size: The current version is much smaller in size compared to previous versions, with a minified size of <6Kb
- Backward compatibility: Most code is still compatible while migrating to newer versions
- Improved importing: Import directly from lit instead of lit-html
- Polyfill support: Add a new polyfill support script for web components
- Renamed APIs: UpdatingElement is now ReactiveElement, @internalProperty is now @state, and NodePart is now ChildPart
Lit.js vs. React
While Lit.js shares some similarities with React, there are significant differences. React has a larger community and more extensive library support, but Lit.js offers faster performance and a smaller memory footprint.
Key Differences
- JSX and templating: Lit.js uses HTML tagged template literals instead of JSX
- Components and props: Lit.js uses LitElement instead of React components
- State and lifecycle methods: Lit.js uses reactive properties and lifecycle callbacks instead of React’s state and lifecycle methods
- React Hooks vs. LitElement: Lit.js doesn’t offer a direct equivalent to React Hooks, but LitElement addresses some of the same issues
Building Web Components with Lit.js
Creating custom web components with Lit.js is straightforward. Start with a simple counter component that increments or decrements a number based on button clicks.
Example Code
“`javascript
import { LitElement, html } from ‘lit’;
class Counter extends LitElement {
static get properties() {
return {
count: { type: Number },
};
}
constructor() {
super();
this.count = 0;
}
render() {
return html
<button @click="${this.increment}">+</button>
<span>${this.count}</span>
<button @click="${this.decrement}">-</button>
}
increment() {
this.count++;
}
decrement() {
this.count–;
}
}
customElements.define(‘x-counter’, Counter);
“`
Should You Switch from React to Lit.js?
While Lit.js offers faster performance and a smaller memory footprint, React remains a popular choice with a large community and extensive library support. If you’re happy with React, there’s no need to switch. However, if you’re working on a project that requires fast performance, Lit.js might be worth considering.