Android Extension failing to compile?

I’m trying to write an android extension modelled after the ones I have already that work but I can’t figure out why I’m getting this compile error:

> Task :deps:licensingservicehelper:compileReleaseKotlin FAILED
e: Supertypes of the following classes cannot be resolved. Please make sure you have the required dependencies in the classpath:
    class, unresolved supertypes: Extension

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':deps:licensingservicehelper:compileReleaseKotlin'.
> Compilation error. See log for more details


import android.content.res.AssetManager;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;

public class HaxeHelper extends Extension {

I’ve tried various imports like “import org.haxe.extension.Extension;” but no luck.

I got it working - I can’t pinpoint it exactly but it was something to do with configuration in build.gradle, the AndroidManifest.xml and my directory structure.