I would personally caution against using an implicit rewriter like this. It is implicit in the sense once you change your schema, there's no documentation about the deprecated queries that are still supported. Yes, old queries will still work, but people who stumble up on them will be very confused as to why they are working, since the schema will say otherwise. Tools like IDE auto-completion for queries[1] or the graphical interface GraphiQL[2] will also ignore these rewrite capabilities and so will not help with writing, editing or running the old-but-still-supported rewritten queries.

Instead of that, i'd personally recommend either sticking with your old schema if the change is as superfluous as the one mentioned on the project's README (changing the type of the `userById(id)` field parameter from `String!` to `ID!`), or shamelessly embracing versioning your fields. In the case example case mentioned on the README, that could mean adding a @deprecated directive on the `userById(id: String!)` field, and then adding a new `userByIdV2(id: ID!)`. Users of the new field can alias it on to a friendlier versionless name, like:

  query {
    user: userByIdV2(id: 123) {
      ...
    }
  }

This way, the changes on the schema are much more explicit: users can still use tools like GraphiQL or schema-aware text editor plugins to write their queries, while receiving feedback about their use of deprecated fields, and what they can do about them :)

[1] Like Intellij IDEA's graphql plugin https://plugins.jetbrains.com/plugin/8097-js-graphql [2] https://github.com/graphql/graphiql