Vibrancy

High-performance, fine-grained reactive state management system.

Features

• 🚀 Zero Dependencies - Lightweight and standalone
• ⚡ Fine-Grained Reactivity - Only update what changes
• 💎 Diamond Dependency Resolution - Handles complex dependency graphs efficiently
• 🔄 Batched Updates - Automatic batching for optimal performance
• 🧹 Automatic Cleanup - Memory-safe with automatic resource disposal
• 📦 Deep Reactive Stores - Proxy-based reactivity for nested objects
• 🔍 TypeScript First - Full TypeScript support with excellent type inference
• 🎯 Predictable - Synchronous and glitch-free updates
• 🏎️ High Performance - Optimized with caching, pooling, and smart invalidation

Installation

npm install vibrancy
# or
yarn add vibrancy
# or
pnpm add vibrancy

Quick Start

import { signal, computed, effect, batch } from 'vibrancy';

// Create reactive signals
const count = signal(0);
const multiplier = signal(2);

// Create computed values that auto-update
const doubled = computed(() => count() * 2);
const result = computed(() => count() * multiplier());

// Create side effects that run when dependencies change
effect(() => {
  console.log(`Count: ${count()}, Result: ${result()}`);
});

// Update signals
count.set(5); // Logs: Count: 5, Result: 10

// Batch updates for efficiency
batch(() => {
  count.set(10);
  multiplier.set(3);
}); // Logs once: Count: 10, Result: 30

Core Concepts

Signals

Signals are the basic reactive primitive. They hold a value and notify dependents when it changes.

const value = signal(initialValue);

// Read the value
console.log(value()); // current value

// Update the value
value.set(newValue);

// Update with a function
value.update(prev => prev + 1);

// Subscribe to changes
const unsubscribe = value.subscribe(newValue => {
  console.log('Value changed:', newValue);
});

// Peek at value without tracking dependencies
const currentValue = value.peek();

Computed

Computed values derive from other reactive values and update automatically.

const computed = computed(() => signal1() + signal2());

Effects

Effects run side effects when their dependencies change.

const dispose = effect(() => {
  console.log('Value changed:', signal());
});

// Clean up when done
dispose();

Stores

Stores provide reactive objects with nested reactivity.

const store = store({
  user: { name: 'John', age: 30 },
  settings: { theme: 'dark' }
});

// Access nested properties reactively
effect(() => {
  console.log(`${store.user.name} uses ${store.settings.theme} theme`);
});

// Update nested values
store.user.name = 'Jane';
store.settings.theme = 'light';

Resources

Resources handle async data fetching with loading states.

const userId = signal(1);

const user = resource(async () => {
  const response = await fetch(`/api/user/${userId()}`);
  return response.json();
});

// Access loading state, error, and data
effect(() => {
  if (user.loading()) {
    console.log('Loading user...');
  } else if (user.error()) {
    console.log('Error:', user.error().message);
  } else {
    console.log('User:', user());
  }
});

// Change userId triggers automatic refetch
userId.set(2);

API Reference

Reactivity

• signal<T>(value: T, options?: SignalOptions) - Create a reactive signal
• computed<T>(fn: () => T, options?: ComputedOptions) - Create a computed value
• effect(fn: () => void, options?: EffectOptions) - Create a side effect
• batch(fn: () => void) - Batch multiple updates
• untrack(fn: () => T) - Read without tracking

Stores

• store<T>(initial: T, options?: StoreOptions) - Create a reactive store
• selector<T, R>(store: Store<T>, fn: (value: T) => R) - Create a store selector
• transaction<T>(fn: () => T) - Batch store updates

Resources

• resource<T>(fetcher: () => Promise<T>, options?: ResourceOptions) - Create an async resource
• asyncComputed<T>(fn: () => Promise<T>, options?: AsyncComputedOptions) - Create async computed values

Context

• getOwner() - Get current reactive owner
• onCleanup(fn: () => void) - Register cleanup function

Advanced Features

• asyncComputed<T>(fn: () => Promise<T>) - Async computed values
• resolveDiamondDependencies() - Handle diamond dependency patterns
• StoreSubscriptionManager - Manage store subscriptions
• StoreMiddlewareManager - Add middleware to stores

Examples

Todo List

import { store, computed, effect } from 'vibrancy';

const todos = store({
  items: [],
  filter: 'all'
});

const activeTodos = computed(() => 
  todos.items.filter(todo => !todo.completed)
);

const visibleTodos = computed(() => {
  switch (todos.filter) {
    case 'active': return activeTodos();
    case 'completed': return todos.items.filter(todo => todo.completed);
    default: return todos.items;
  }
});

effect(() => {
  console.log(`You have ${activeTodos().length} active todos`);
});

// Add a todo
todos.items.push({ text: 'Learn Vibrancy', completed: false });

Shopping Cart

import { signal, computed, effect } from 'vibrancy';

const items = signal([
  { price: 10, quantity: 2 },
  { price: 5, quantity: 3 }
]);

const total = computed(() => 
  items().reduce((sum, item) => sum + item.price * item.quantity, 0)
);

effect(() => {
  console.log(`Total: $${total()}`);
});

// Update items
items.update(list => [...list, { price: 20, quantity: 1 }]);

License

MIT