Manifold is an amazing piece of engineering. Scott McKinney, the author, used to work on Gosu but mostly focuses on this now.

He added GraphQL support a few weeks ago:

https://github.com/manifold-systems/manifold-sample-graphql-...

You can just drop graphql files in your resources directory and start coding against them as type-safe interfaces immediately, no code-gen required.

The @Jailbreak annotation is awesome too.