Preact Signal Guide

A guide to using Preact's signals library for efficient, fine-grained reactivity that updates the DOM directly without virtual DOM diffing.

Usage

Ask about Preact signals, computed values, effects, or performance optimization.

Examples

• "Create a counter with Preact signals"
• "How do signals improve performance over useState?"
• "Use computed signals for derived state"

Guidelines

• Use signal() for reactive primitive values
• Use computed() for values derived from other signals
• Use effect() for side effects that react to signal changes
• Signals can be used outside components for global state
• Pass signal objects directly to JSX for optimal updates