Dagger (dagger.io) has its own container execution stack, and supports dagger-in-dagger natively, with logical scoping, and without depth limit. Would love to show you both a demo, if you're interested!

(Disclaimer, I'm the CEO of Dagger)

I founded Docker, and lack of proper nesting support was always a pet pieve of mine. I couldn't fix it in Docker, so I fixed it in Dagger instead :)