cmd-launcher

A minimal command line Minecraft launcher.
EN | DE

• Installation
  • Building from source
• Usage
  • Creating an instance
  • Starting the game
  • Authentication
  • Instance Configuration
  • Search

API Documentation

Installation

Binaries

You can download prebuilt binaries from the Releases tab here on GitHub.
Builds of the latest commit are available at nightly.link.

Via go install

Make sure you have Go installed.

To install the latest version, run:

go install github.com/telecter/cmd-launcher@latest

Replace latest with main for the latest commit.

Building from source

1. Clone the repository: git clone https://github.com/telecter/cmd-launcher
2. In the source directory, run go run . to compile and run the launcher.
3. Once you are ready, compile the executable with go build .

Usage

Use the --help flag to get the usage information of any command.

Instances

Creating an instance
To create a new instance, use the inst create command.
You can use the --loader, -l flag to set the mod loader. Forge, NeoForge, Fabric, and Quilt are all supported. If you want to select a specific version of the loader, use the --loader-version flag. Otherwise, the latest applicable version is chosen.

Use the --version, -v flag to set the game version. If no value is supplied, the latest release is used. Acceptable values also include release or snapshot for the latest of either.

When starting the game, the launcher will attempt to download a Java runtime from Mojang. If it can't find a suitable one, you will need to set one manually in the instance configuration.

cmd-launcher inst create -v 1.21.8 -l fabric CoolInstance

Deleting instances
If you want to delete an instance, use the inst delete command followed by the instance name.

Starting the Game

Important

This launcher has not been tested for versions < 1.14. It may not work, but I am working on fixing these issues.

To start Minecraft, simply run the start command followed by the name of the instance you want to start.

cmd-launcher start CoolInstance

To set game options and override instance configuration, you can set specific flags on the start command. These can be viewed in the help text.

Verbosity
To increase the verbosity of the launcher, use the --verbosity flag. It can be set to either:

• info - default, no extra logging
• extra - more information when starting the game
• debug - debug information useful for debugging the launcher

Authentication

If you want to play the game in online mode, you will need to add a Microsoft account.

To do this, use the auth login command. As part of Microsoft's OAuth2 flow, the default web browser will be opened to complete the authentication. This can be avoided with the --no-browser flag.
The launcher will automatically attempt to start the game in online mode if there is an account present.

To play in offline mode, just pass the -u, --username <username> flag to the start command to set your username and the game will automatically launch in offline mode.

You can log out via the auth logout command.

Instance Configuration

To change configuration values for an instance, navigate to the instance directory and open the instance.toml file.

Configurable values are:

• Game version
• Mod loader and version (if not vanilla)
• Window resolution
• Java executable path (if empty, a Mojang-provided Java runtime will be downloaded)
• Custom JAR path to use instead of downloading the normal client JAR
• Extra Java args
• Minimum and maximum memory

As mentioned previously, these values can be overriden with command line flags.

Example instance.toml file

game_version = '1.21.8'
mod_loader = 'fabric'
mod_loader_version = '0.16.14'

[config]
# Path to a Java executable. If blank, a Mojang-provided JVM will be downloaded.
java = '/usr/bin/java'
# Extra arguments to pass to the JVM
java_args = ''
# Path to a custom JAR to use instead of the normal Minecraft client
custom_jar = ''
# Minimum game memory, in MB
min_memory = 512
# Maximum game memory, in MB
max_memory = 4096

# Game window resolution
[config.resolution]
width = 1708
height = 960

Search

The search command can search for Minecraft or mod loader versions. It defaults to searching for game versions, but can also be used to search for Fabric, Quilt, and Forge versions.

cmd-launcher search [<query>] [--kind {versions, fabric, quilt, forge}]