WinterCore MC

WinterCore MC (wintercore-mc) is a powerful Node.js/TypeScript library designed to simplify Minecraft Java Edition launcher development. It provides a complete solution for game launching, authentication, mod loading, and asset management without the complexity of handling manifests, libraries, or Java runtimes manually.

🎯 What is WinterCore MC?

WinterCore MC eliminates the tedious work of building Minecraft launchers from scratch. Whether you're creating a custom launcher for a modpack, building a server management tool, or developing a gaming platform, WinterCore MC handles all the low-level Minecraft launching logic so you can focus on your user experience.

✨ Key Features

• 🚀 One-line game launching - Launch any Minecraft version with minimal configuration
• 🔐 Authentication ready - Accepts any auth object (Microsoft, Mojang, or custom servers)
• 🔧 Universal mod loader support - Forge, NeoForge, Fabric, Quilt, and Legacy Fabric
• 📦 Intelligent asset management - Automatic download, verification, and caching
• ⚡ High-performance downloads - Parallel downloading with progress tracking and retry logic
• 🎯 Smart Java detection - Automatic JVM discovery and version management
• 📊 Real-time events - Progress, speed, extraction, and error events
• 🛡️ Robust file handling - SHA-1 verification, resume support, and error recovery
• 🖥️ Cross-platform ready - Windows, macOS, and Linux compatibility
• 🎮 Instance management - Support for multiple game profiles and configurations
• 🔍 Server status ping - Query Minecraft server status directly

📦 Installation

npm install wintercore-mc

🚀 Quick Start

Basic Launch Example

import { Launch } from 'wintercore-mc';

const launcher = new Launch();

// You need to provide an authenticator object with these fields:
// { access_token, client_token, uuid, name, user_properties, meta: { type } }
// You can use any Microsoft/Mojang/AZauth library of your choice
const auth = await YourAuthProvider.login();

// Launch Minecraft
launcher.Launch({
    path: '/path/to/.minecraft',
    version: '1.20.4',
    authenticator: auth,
    memory: {
        min: '2G',
        max: '4G'
    },
    loader: {
        type: 'fabric',
        build: 'latest',
        enable: true
    },
    verify: false
});

// Listen to events
launcher.on('progress', (downloaded, total, file) => {
    console.log(`Downloading: ${file} (${downloaded}/${total})`);
});

launcher.on('data', (data) => {
    console.log(data); // Minecraft console output
});

launcher.on('close', (info) => {
    console.log(`Minecraft closed. Code: ${info.code}`);
});

📖 API Reference

Launch

The main class for launching Minecraft instances. Extends EventEmitter.

Constructor

const launcher = new Launch();

Methods

Launch(options: LaunchOPTS)

Starts the launch process with the provided options.

launcher.Launch({
    path: string,              // Absolute path to Minecraft root directory
    version: string,           // Minecraft version (e.g., '1.20.4', 'latest_release')
    authenticator: any,        // Auth object from Microsoft, Mojang, or AZauth
    timeout?: number,          // Connection timeout in milliseconds (default: 10000)
    instance?: string,         // Instance name for isolated game data
    detached?: boolean,        // Run Minecraft process independently (default: false)
    downloadFileMultiple?: number,  // Concurrent downloads (default: 5, max: 30)
    bypassOffline?: boolean,   // Skip online checks (default: false)
    verify?: boolean,          // Verify game files on launch (default: false)
    ignored?: string[],        // Files to ignore from instance
    loader?: {
        path?: string,         // Path to loader directory (relative to MC root)
        type?: string,         // 'forge', 'neoforge', 'fabric', 'legacyfabric', 'quilt'
        build?: string,        // 'latest', 'recommended', or specific version
        enable?: boolean       // Enable mod loader (default: false)
    },
    mcp?: any,                 // MCPatcher directory
    JVM_ARGS?: string[],       // Custom JVM arguments
    GAME_ARGS?: string[],      // Custom game arguments
    java?: {
        path?: string,         // Absolute path to Java binaries
        version?: string,      // Java version number
        type: string           // 'jdk', 'jre', 'testimage', 'debugimage', etc.
    },
    screen?: {
        width?: number,        // Window width
        height?: number,       // Window height
        fullscreen?: boolean   // Fullscreen mode (default: false)
    },
    memory?: {
        min?: string,          // -Xms value (default: '1G')
        max?: string           // -Xmx value (default: '2G')
    },
    resourcePacks?: Array<{    // Resource packs to enable
        name: string,
        fileName: string,
        filePath: string
    }>,
    url?: string | null,       // URL to launcher backend (Selvania setup)
    intelEnabledMac?: boolean  // Intel Mac support flag
});

cancel()

Cancels the launch process and terminates the Minecraft process if running.

await launcher.cancel();

launching: boolean

Returns whether a launch is currently in progress.

if (launcher.launching) {
    console.log('Launch in progress...');
}

cancelled: boolean

Returns whether the launch was cancelled.

if (launcher.cancelled) {
    console.log('Launch was cancelled');
}

getMemoryStats()

Returns memory usage statistics.

const stats = launcher.getMemoryStats();
console.log(stats); // { pools: number, totalObjects: number, heapUsed: number }

forceGarbageCollection()

Forces garbage collection (requires --expose-gc flag).

launcher.forceGarbageCollection();

Events

Event	Parameters	Description
progress	(downloaded: number, total: number, file: string)	Download progress updates
speed	(speed: number)	Download speed
estimated_time	(time: number)	Estimated time remaining
extract	(progress: any)	File extraction progress
check	(progress: any, size: any, element: any)	File verification progress
patch	(patch: any)	Mod loader patching progress
data	(data: string)	Minecraft console output
close	(info: { code, signal, runtime, isCrash, timeSinceLastOutput })	Game closed
complete	(info: { message, process, performance })	Launch completed successfully
error	(error: any)	Error occurred
cancelled	(info: { message, wasLaunching, hadProcess })	Launch cancelled
downloads_complete	(info: { message, fileCount })	All downloads finished

---

Authenticator Interface

WinterCore MC doesn't include authentication built-ins. Instead, it accepts any authenticator object that follows this interface:

interface Authenticator {
    access_token: string;     // Minecraft access token
    client_token: string;     // Client identifier
    uuid: string;             // Player UUID
    name: string;             // Player username
    user_properties: string;  // Usually '{}'
    meta: {
        type: string;         // 'Xbox', 'Mojang', or custom
        online: boolean;      // Whether account is premium
    };
    xboxAccount?: {
        xuid: string;
        gamertag: string;
        ageGroup: string;
    };
}

You can use any authentication library or implement your own. The launcher only reads these fields to pass to the game process.

---

Status Server

Query Minecraft server status information.

import { Status } from 'wintercore-mc';

const server = new Status('play.hypixel.net', 25565);

try {
    const status = await server.getStatus();
    console.log(status);
    // {
    //     error: false,
    //     ms: 45,
    //     version: '1.8-1.20',
    //     playersConnect: 12345,
    //     playersMax: 50000
    // }
} catch (error) {
    console.error('Server is offline or unreachable');
}

---

Downloader

Advanced file downloader with progress tracking and retry logic.

import { Downloader } from 'wintercore-mc';

const downloader = new Downloader();

// Single file download
await downloader.downloadFile(url, dirPath, fileName);

// Multiple concurrent downloads
await downloader.downloadFileMultiple(files, totalSize, concurrent, timeout, signal);

// Events
downloader.on('progress', (downloaded, total, file) => {
    console.log(`Progress: ${downloaded}/${total}`);
});

downloader.on('speed', (speed) => {
    console.log(`Speed: ${speed} bytes/s`);
});

downloader.on('estimated', (time) => {
    console.log(`Estimated time: ${time}s`);
});

---

MemoryManager

Memory pooling utilities for performance optimization.

import { MemoryManager, StringBuilder, BufferedFileReader } from 'wintercore-mc';

const memoryManager = MemoryManager.getInstance();

// Get object from pool or create new
const stringBuilder = memoryManager.getFromPool('StringBuilder', () => new StringBuilder());

// Return to pool for reuse
memoryManager.returnToPool('StringBuilder', stringBuilder, (obj) => obj.clear());

// Clear all pools
memoryManager.clearPools();

// Force garbage collection
memoryManager.forceGC();

// Get memory stats
const stats = memoryManager.getMemoryStats();

---

PerformanceMonitor

Monitors launch and download performance metrics.

import PerformanceMonitor from 'wintercore-mc';

const monitor = PerformanceMonitor.getInstance();
monitor.startLaunchMonitoring();

// Later...
const metrics = monitor.stopMonitoring();

📚 Advanced Usage

Instance Management

Launch multiple Minecraft instances with isolated game data:

launcher.Launch({
    path: '/path/to/.minecraft',
    instance: 'MyModpack',  // Creates /path/to/.minecraft/instances/MyModpack/
    version: '1.20.1',
    authenticator: auth,
    loader: {
        type: 'forge',
        build: 'latest',
        enable: true
    }
});

Custom JVM and Game Arguments

launcher.Launch({
    path: '/path/to/.minecraft',
    version: '1.20.4',
    authenticator: auth,
    JVM_ARGS: [
        '-XX:+UseG1GC',
        '-XX:+UnlockExperimentalVMOptions',
        '-Dfml.ignoreInvalidMinecraftCertificates=true'
    ],
    GAME_ARGS: [
        '--width', '1920',
        '--height', '1080'
    ]
});

Resource Packs

launcher.Launch({
    path: '/path/to/.minecraft',
    version: '1.20.4',
    authenticator: auth,
    resourcePacks: [
        {
            name: 'Faithful 64x',
            fileName: 'Faithful-64x.zip',
            filePath: '/path/to/Faithful-64x.zip'
        }
    ]
});

Mod Loader Configuration

// Fabric
loader: {
    type: 'fabric',
    build: '0.16.3',
    enable: true
}

// Forge
loader: {
    type: 'forge',
    build: 'recommended',
    enable: true
}

// NeoForge
loader: {
    type: 'neoforge',
    build: 'latest',
    enable: true
}

// Custom loader path
loader: {
    path: './custom-loader',
    type: 'fabric',
    build: '0.15.0',
    enable: true
}

Cancellation

const launcher = new Launch();

// Start launch
launcher.Launch({ /* options */ });

// Cancel after 5 seconds
setTimeout(async () => {
    await launcher.cancel();
    console.log('Launch cancelled');
}, 5000);

Server Status Monitoring

const servers = [
    new Status('hypixel.net', 25565),
    new Status('mineplex.com', 25565),
    new Status('cubecraft.net', 25565)
];

for (const server of servers) {
    try {
        const status = await server.getStatus();
        console.log(`${server.ip}: ${status.playersConnect}/${status.playersMax} players`);
    } catch (error) {
        console.log(`${server.ip}: Offline`);
    }
}

🏗️ Architecture

src/
├── Index.ts              # Main exports
├── Launch.ts             # Core launcher logic
├── Minecraft/
│   ├── Minecraft-Json.ts       # Version manifests
│   ├── Minecraft-Libraries.ts  # Library management
│   ├── Minecraft-Assets.ts     # Asset management
│   ├── Minecraft-Java.ts       # JVM download/management
│   ├── Minecraft-Loader.ts     # Mod loader installation
│   ├── Minecraft-Bundle.ts     # File bundle management
│   ├── Minecraft-Arguments.ts  # Launch argument generation
│   └── Minecraft-Lwjgl-Native.ts # LWJGL native libraries
├── Minecraft-Loader/
│   ├── index.ts          # Loader index
│   ├── patcher.ts        # Loader patching
│   └── loader/           # Loader-specific implementations
├── StatusServer/
│   ├── status.ts         # Server status pinger
│   └── buffer.ts         # Protocol buffer utilities
└── utils/
    ├── Downloader.ts     # Advanced downloader
    ├── MemoryManager.ts  # Memory pooling
    ├── PerformanceMonitor.ts  # Performance tracking
    ├── Errors.ts         # Error handling
    ├── Index.ts          # Utility functions
    └── unzipper.ts       # ZIP extraction

🔧 Development

# Install dependencies
npm install

# Development mode (watch)
npm run dev

# Build
npm run build

📝 Requirements

• Node.js >= 22.13.0
• TypeScript 5.x

📄 License

MIT License

🔗 Links

• GitHub Repository
• Report Issues
• npm Package