Installation

How to Download the latest version.

The latest source build can be downloaded from the following locations:

1. builds.kolmafia.us
2. the GitHub releases page.

Both of these sources have tested versions that are posted shortly after developers change code.

The GitHub releases page contains both the KoLmafia-xxxxx.jar java binaries and installers for an experimental version that includes a bundled version of Java. If you use the installers, they manage the Java dependency listed below, but it can be more difficult to troubleshoot issues.

Dependencies

Java 11 or better (Java 17 recommended)

KoLmafia depends on finding Java 11 or better. The recommended version is linked at the top of every page of kolmafia.us. If you are executing KoLmafia from a jarfile, you will need to install Java first.

If you do not have a recent version of Java, the recommended version (as of this writing) is Java 17.

Testing your Java installation

From a Command Prompt (or Terminal) window, enter java -version

If that returns something like this, you should be good to go.

Michaels-MBP:~ mcroft$ java -version
openjdk version "16.0.1" 2021-04-20
OpenJDK Runtime Environment Zulu16.30+15-CA (build 16.0.1+9)
OpenJDK 64-Bit Server VM Zulu16.30+15-CA (build 16.0.1+9, mixed mode, sharing)

Troubleshooting Runtime Issues

Java Errors

Please be aware that some older versions of Java do not get completely replaced when installing a newer version. Usually this happens with Java 8 JRE and Java 11+ JDKs. If that makes no sense, just delete Java 8.

If you get a message like this:Error: A JNI error has occurred, please check your installation and try again. Please read this announcement.

Scaling support on HiDPI Monitors

The default builds target Java and use Java Swing to provide its user interface. Java Swing support for HiDPI on Linux requires that you execute the '.jar' file with an option set as follows: java -Dsun.java2d.uiScale=<multiplier> -jar <jarfile> ;e.g. in my case, '<multiplier>' should be '2'.