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kotlinlang

Not 100% sure about your case, but now these extensions for configurations generated only when you apply plugin for a project with particular configuration, they not available globally anymore. So your script plugin has no access to configuration because extension not available in his scope. Probably you could apply java/kotlin plugin to get access to static configurations, but not sure

But also, you can use dynamic configurations and gradle will resolve them in runtime (“compile”)

As I know there is a lot of tasks how to improve script plugins, you can check github issues