Is there any library that will take an object and attach methods according to its

__typename

?

What type of methods ? CRUD and stuff ?

Yes, same question. If you want a autogenerated GraphQL API, you can look into nexus prisma: https://github.com/prisma/nexus-prisma If you want to generate typescript typings you can look into GraphQL code generator: https://github.com/dotansimha/graphql-code-generator

I was looking for something like selectors on the client side