Gradle 4.7+ has a new feature to let annotation processors run incrementally. In order to make that work, Immutables has to tell Gradle how its annotation processor behave during execution.

For details see:

https://docs.gradle.org/nightly/userguide/java_plugin.html#sec:incremental_annotation_processing

gradle/gradle#5277

Supporting this feature, would greatly reduce build times using Gradle.