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# Size Limit Preset for Big Libraries
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Size Limit preset for big open source libraries (> 10 kB) that combines webpack, file, and time plugins to provide comprehensive performance monitoring including tracking the time of JavaScript download and execution for the library and all its dependencies.
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## Package Information
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- **Package Name**: @size-limit/preset-big-lib
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- **Package Type**: npm
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- **Language**: JavaScript (ES Module)
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- **Installation**: `npm install @size-limit/preset-big-lib`
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- **Peer Dependencies**: size-limit@11.2.0
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## Core Imports
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```javascript
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import preset from "@size-limit/preset-big-lib";
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```
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For CommonJS (if supported by bundler):
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```javascript
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const preset = require("@size-limit/preset-big-lib");
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```
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**Package.json access:**
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```javascript
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import packageJson from "@size-limit/preset-big-lib/package.json";
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```
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## Basic Usage
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This preset is designed to be used with Size Limit configuration. It provides a pre-configured combination of plugins for comprehensive performance monitoring of large libraries.
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```javascript
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// size-limit.config.js
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import preset from "@size-limit/preset-big-lib";
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export default [
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  {
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    name: "My Big Library",
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    path: "dist/index.js",
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    plugins: preset,
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    limit: "50 kB"
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  }
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];
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```
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Or in package.json:
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```json
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{
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  "size-limit": [
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    {
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      "name": "My Big Library", 
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      "path": "dist/index.js",
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      "plugins": ["@size-limit/preset-big-lib"],
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      "limit": "50 kB"
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    }
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  ]
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}
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```
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## Architecture
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This preset combines three Size Limit plugins:
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- **@size-limit/webpack**: Provides webpack bundling analysis for accurate dependency tracking
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- **@size-limit/file**: Measures the actual file size of the bundled output
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- **@size-limit/time**: Measures JavaScript download and execution time
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The preset exports these plugins as a combined array, making it easy to apply comprehensive performance monitoring to large libraries without manual plugin configuration.
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## Capabilities
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### Preset Configuration
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The main and only export of this package - a combined array of Size Limit plugins optimized for big libraries.
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```javascript { .api }
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/**
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 * Size Limit preset combining webpack, file, and time plugins
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 * Exports: [...webpack, ...file, ...time]
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 */
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export default Array<SizeLimitPlugin>;
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interface SizeLimitPlugin {
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  // Internal Size Limit plugin interface
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  // Specific structure depends on Size Limit implementation
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}
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```
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**Usage:**
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The preset is used by importing it and applying it to Size Limit configuration. When applied, it provides:
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1. **Webpack bundling analysis** - Analyzes the library and all its dependencies through webpack
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2. **File size measurement** - Tracks the actual file size of the bundled output  
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3. **Execution time measurement** - Measures JavaScript download and execution time
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**Configuration Example:**
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```javascript
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import preset from "@size-limit/preset-big-lib";
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// Apply to Size Limit configuration
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const config = [
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  {
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    name: "Main Bundle",
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    path: "dist/main.js", 
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    plugins: preset, // Uses the combined plugin array
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    limit: "100 kB"
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  }
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];
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```
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## Dependencies
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This preset includes the following Size Limit plugins as dependencies:
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- **@size-limit/webpack@11.2.0** - Webpack bundling analysis plugin
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- **@size-limit/file@11.2.0** - File size measurement plugin  
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- **@size-limit/time@11.2.0** - JavaScript execution time measurement plugin
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- **size-limit@11.2.0** - Core Size Limit library (also required as peer dependency)
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The preset simply re-exports these plugins in a combined array format, providing a convenient way to apply comprehensive performance monitoring to large libraries without manually configuring individual plugins.