Hi, I'm on the Play team. We've got a number of projects showing compile time injection:

Java compile time DI:

https://github.com/playframework/play-java-compile-di-exampl...

Java compile time DI using Dagger 2:

https://github.com/playframework/play-java-dagger2-example

Scala compile time DI:

https://github.com/playframework/play-scala-compile-di-examp...

Scala compile time DI with Macwire:

https://github.com/playframework/play-scala-macwire-di-examp...

Thanks!