this is more of a general graphql question but is there a consensus on code first vs schema first these days?

Not really, it is more like tabs vs spaces. Both works and have their pros and cons. It is up-to you to choose which cons you can easily deal with.

Niko spoke about this in GraphQL conf, I guess the videos are available now, maybe you can check that out!

You should try both and see. I’m sure you’d fall in love with the code-first approach (nexus).