Just as the title says, that aren't kept are missing from the output JAR entirely. This is my config: -libraryjars 'C:\Program Files\Java\jre1.8.0_162\lib\rt.jar' -printmapping proguard.map -dontwarn -keep class kotlin.** { <fields>; <methods>; } -keep class kotlin.Metadata { <fields>; <methods>; } -keepclassmembers class **$WhenMappings { <fields>; } -keepclassmembers class kotlin.Metadata { public <methods>; } -keep class !me.glorantq.** { <fields>; <methods>; } Everything outside of me.glorantq...