Extending types for rules?

[leo-petrucci]

In my API rules I sometimes need to make requests using Prisma. This works, but the typings aren't great:

rule()(async (_parent, _args, { prisma })

In this example prisma is of type any.

How would I go about extending graphql-shield's types so I can specify what type my context is within my rules?

I tried creating a file /types/graphql-shield.d.ts:

import GraphqlShield from "graphql-shield/dist/types";
import { Context } from "_lib/context";

declare module "graphql-shield/dist/types" {
  export declare type IRuleFunction = (
    parent: any,
    args: any,
    ctx: Context,
    info: GraphQLResolveInfo
  ) => IRuleResult | Promise<IRuleResult>;
}

As I've seen this work in other packages, but it didn't work. I'll be honest I'm not too familiar on how this part of typescript works.

Any help?