This is my first plugin. May or may not lag!
Run the startfire command to start setting players on fire.
Run the stopfire command to stop setting players on fire.
gradlew jar / ./gradlew jar
Output jar should be in build/libs.
Simply place the output jar from the step above in your server's config/mods directory and restart the server.
List your currently installed plugins/mods by running the mods command.