I agree with you. Not many things in life are done as they were supposed to be done. Hindsight is 20/20.
I built this tool to help with existing codebases. At IFTTT specifically, we saw an instant 60% reduction in database IOPS. Not too bad for 1~2 days of coding.
I have been using this tool for about 2 months at Segment, and I have to say, the experience is just incredible. Being able to catch syntax errors and get autocompletion ahead of time is a pretty massive productivity boost.
The main idea was to feed the Active Record preloader with hints from the GraphQL queries.
Of course this only works well when your GraphQL schema matches your database schema (which is most cases anyway in my experience).
https://github.com/nettofarah/graphql-query-resolver
Here's a video of a talk I gave about the approach at GraphQL Europe in 2017:
https://www.youtube.com/watch?v=TIzEZJuDpIQ