Features
- Compile-time reactivity with no runtime overhead
- Runes API for explicit reactive declarations
- Built-in transitions, animations, and motion
- Scoped styles by default in .svelte files
- Minimal boilerplate with concise syntax
Pros
- Smallest bundle sizes among major frameworks
- Intuitive syntax that feels close to vanilla HTML/JS
- Excellent performance with no virtual DOM diffing
- Built-in accessibility warnings during compilation
Cons
- Smaller ecosystem and community than React or Vue
- Fewer job opportunities compared to React
- Svelte 5 runes migration from older reactivity model
Overview
Svelte is a frontend framework that takes a fundamentally different approach from React and Vue. Instead of doing work in the browser using a virtual DOM, Svelte shifts that work to a compile step that happens at build time. The compiler transforms your declarative component code into efficient imperative JavaScript that surgically updates the DOM.
Svelte 5 introduced runes — a set of compiler-powered primitives like $state, $derived, and $effect that make reactivity explicit and composable. This approach gives you fine-grained reactivity without the overhead of a runtime framework, resulting in smaller bundles and faster runtime performance.
When to Use
Svelte is ideal for projects where bundle size and runtime performance are critical, such as embedded widgets, performance-sensitive applications, or content-heavy sites. It’s also a great choice when you value developer experience and want to write less boilerplate code.
Getting Started
npx sv create my-app
cd my-app && npm install && npm run dev<script>
let count = $state(0);
</script>
<button onclick={() => count++}>Count: {count}</button>