Conditions for Kapt and incremental processing

I’m using https://github.com/TouK/krush in my project and gradle is warning me that it is stopping incremental processing from happening. So, I have cloned the repo and specified kapt.use.worker.api=true and kapt.incremental.apt=true in the library’s gradle.properties. However, it is still preventing increment processing. So, I’m wondering if someone can point me to a resource to better understand the conditions necessary for incremental processing or suggest any other things I should look at.

You need to mark the annotation processor to support incremental compilation.
Basically you need to create a file META-INF/gradle/incremental.annotation.processors and add the following

qualifiedNameOfProcessorClass,<incrementalType>

the options are aggregating, isolating and dynamic.
https://docs.gradle.org/current/userguide/java_plugin.html#sec:incremental_annotation_processing