CmlLib.Core 3.3.6

There is a newer version of this package available.
See the version list below for details.
dotnet add package CmlLib.Core --version 3.3.6                
NuGet\Install-Package CmlLib.Core -Version 3.3.6                
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="CmlLib.Core" Version="3.3.6" />                
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add CmlLib.Core --version 3.3.6                
#r "nuget: CmlLib.Core, 3.3.6"                
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.
// Install CmlLib.Core as a Cake Addin
#addin nuget:?package=CmlLib.Core&version=3.3.6

// Install CmlLib.Core as a Cake Tool
#tool nuget:?package=CmlLib.Core&version=3.3.6                


Minecraft Launcher Library

<img src='' width=128>

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CmlLib.Core is a Minecraft launcher library for .NET
It supports all versions, including Forge




  • Asynchronous APIs
  • Mojang Authentication
  • Microsoft Xbox Live Login
  • Download the game files from the Mojang file server
  • Launch any version (tested up to 1.18.2)
  • Launch Forge, Optifine, FabricMC, LiteLoader or any other custom version
  • Install Java runtime
  • Install LiteLoader, FabricMC
  • Launch with options (direct server connecting, screen resolution)
  • Cross-platform (Windows, Linux, macOS)

Go to the wiki for all features


Install the CmlLib.Core Nuget package

or download the DLL files in Releases and add references to them in your project.

Write this at the top of your source code:

using CmlLib.Core;
using CmlLib.Core.Auth;


There are many features for custom launchers. Read the wiki to see all of the features.
Official documentation: wiki

Quick start

Microsoft Xbox Login


Mojang Login

Login Process

var login = new MLogin();
var response = login.TryAutoLogin();

if (!response.IsSuccess) // failed to automatically log in
    var email = Console.ReadLine();
    var pw = Console.ReadLine();
    response = login.Authenticate(email, pw);

    if (!response.IsSuccess)
         throw new Exception(response.Result.ToString()); // failed to log in

// This session variable is the result of logging in and is used in MLaunchOption, in the Launch part below.
var session = response.Session;

Offline Login

// This session variable is the result of logging in and is used in MLaunchOption, in the Launch part below.
var session = MSession.GetOfflineSession("USERNAME");


// increase connection limit to fast download
System.Net.ServicePointManager.DefaultConnectionLimit = 256;

//var path = new MinecraftPath("game_directory_path");
var path = new MinecraftPath(); // use default directory

var launcher = new CMLauncher(path);

// show launch progress to console
launcher.FileChanged += (e) =>
    Console.WriteLine("[{0}] {1} - {2}/{3}", e.FileKind.ToString(), e.FileName, e.ProgressedFileCount, e.TotalFileCount);
launcher.ProgressChanged += (s, e) =>
    Console.WriteLine("{0}%", e.ProgressPercentage);

var versions = await launcher.GetAllVersionsAsync();
foreach (var item in versions)
    // show all version names
    // use this version name in CreateProcessAsync method.

var launchOption = new MLaunchOption
    MaximumRamMb = 1024,
    Session = session, // replace this with login session value. ex) Session = MSession.GetOfflineSession("hello")

    //ScreenWidth = 1600,
    //ScreenHeight = 900,
    //ServerIp = ""

//var process = await launcher.CreateProcessAsync("input version name here", launchOption);
var process = await launcher.CreateProcessAsync("1.15.2", launchOption); // vanilla
// var process = await launcher.CreateProcessAsync("1.12.2-forge1.12.2-", launchOption); // forge
// var process = await launcher.CreateProcessAsync("1.12.2-LiteLoader1.12.2"); // liteloader
// var process = await launcher.CreateProcessAsync("fabric-loader-0.11.3-1.16.5") // fabric-loader



Sample Code

Product Compatible and additional computed target framework versions.
.NET net5.0 was computed.  net5.0-windows was computed.  net6.0 was computed.  net6.0-android was computed.  net6.0-ios was computed.  net6.0-maccatalyst was computed.  net6.0-macos was computed.  net6.0-tvos was computed.  net6.0-windows was computed.  net7.0 was computed.  net7.0-android was computed.  net7.0-ios was computed.  net7.0-maccatalyst was computed.  net7.0-macos was computed.  net7.0-tvos was computed.  net7.0-windows was computed.  net8.0 was computed.  net8.0-android was computed.  net8.0-browser was computed.  net8.0-ios was computed.  net8.0-maccatalyst was computed.  net8.0-macos was computed.  net8.0-tvos was computed.  net8.0-windows was computed. 
.NET Core netcoreapp3.0 was computed.  netcoreapp3.1 was computed. 
.NET Standard netstandard2.1 is compatible. 
.NET Framework net462 is compatible.  net463 was computed.  net47 was computed.  net471 was computed.  net472 was computed.  net48 was computed.  net481 was computed. 
MonoAndroid monoandroid was computed. 
MonoMac monomac was computed. 
MonoTouch monotouch was computed. 
Tizen tizen60 was computed. 
Xamarin.iOS xamarinios was computed. 
Xamarin.Mac xamarinmac was computed. 
Xamarin.TVOS xamarintvos was computed. 
Xamarin.WatchOS xamarinwatchos was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.

NuGet packages (2)

Showing the top 2 NuGet packages that depend on CmlLib.Core:

Package Downloads

Minecraft Forge Installer


Minecraft login with Microsoft Xbox account migrated to work with the UnoPlatform

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
4.0.0 227 7/7/2024
4.0.0-beta.2 114 6/9/2024
4.0.0-beta.1 114 3/29/2024
3.3.10 1,240 3/9/2024
3.3.9 572 2/1/2024
3.3.8 1,502 10/14/2023
3.3.7 2,594 6/26/2023
3.3.6 2,518 1/22/2023
3.3.5 7,354 12/20/2021
3.3.4 916 12/13/2021
3.3.3 2,212 10/4/2021
3.3.2 908 9/5/2021
3.3.1 1,323 6/22/2021
3.3.0 903 6/14/2021
3.2.0 849 6/2/2021
3.2.0-pre3 629 5/25/2021
3.2.0-pre1 630 4/8/2021
3.1.1 1,220 2/11/2021
3.1.0 930 12/27/2020
3.0.0 1,088 8/25/2020
3.0.0-alpha3 739 8/24/2020
3.0.0-alpha 836 7/3/2020
2.0.2 1,047 5/31/2020
2.0.1 948 5/31/2020
2.0.0 1,022 5/17/2020
0.2.0 1,065 4/13/2020
0.1.0 1,029 4/6/2020