Yarn is a set of open, unencumbered Minecraft mappings, free for everyone to use under the Creative Commons Zero license. The intention is to let everyone mod Minecraft freely and openly, while also being able to innovate and process the mappings as they see fit.
To use Yarn-de-obfuscated Minecraft for Minecraft modding or as a dependency in a Java project, you can use loom Gradle plugin. See fabric wiki tutorial for more information.
To obtain a de-obfuscated Minecraft jar, ./gradlew mapNamedJar
will generate a jar named like <minecraft version>-named.jar
,
which can be sent to a decompiler for de-obfuscated code.
Please note to run the yarn build script Java 16 or higher is required!
Please remember that copying and pasting mappings from alternate projects under more restrictive licenses (such as MCP, Spigot's or Mojang's obfuscation maps) is completely forbidden without explicit permission from the owners of said mappings to distribute the names under the CC0 license. This includes using the names from those mappings for inspiration. Discussing the naming approaches used in said projects is also not welcome - you have been warned. However, it is a good idea to consult name changes with other people - use pull requests or our community spaces to ask questions!
Please have a look at the naming conventions before submitting mappings.
- Fork and clone the repo
- Run
./gradlew yarn
(Linux, macOS) orgradlew yarn
(Windows) to open Enigma, a user interface to easily edit the mappings - Commit and push your work to your fork
- Open a pull request with your changes
Yarn uses Gradle to provide a number of utility tasks for working with the mappings.
Setup and download and launch the latest version of Enigma automatically configured to use the merged jar and the mappings.
Compared to launching Enigma externally, the gradle task adds a name guesser plugin that automatically maps enums and a few constant field names.
Same as above, but unpicks the constants and launches Enigma with them. Can be a little slower to get going.
Build a GZipped archive containing a tiny mapping between official (obfuscated), intermediary, and yarn names ("named") and packages Enigma mappings into a zip archive..
Builds a de-obfuscated jar with yarn mappings and auto-mapped fields (enums, etc.). Unmapped names will be filled with intermediary names.
Decompile the mapped source code. Note: This is not designed to be recompiled.
Downloads the client and server Minecraft jars for the current Minecraft version to .gradle/minecraft
Merges the client and server jars into one merged jar, located at VERSION-merged.jar
in the mappings
directory where VERSION
is the current Minecraft version.