typescript and express js. change res json `Response` type

in typescript, I am trying to overwrite the express's Response json object to be a specific type of object to always be used

for example, I want to enforce a interface type that would error out if the following format was not followed

  return res.status(200).json({
    data: ["a", {"a": "b"}],
    success: true,
  });

I attempted to use dts-gen --m express -f src/types/express.d.ts to create the declaration file to modify but it ended in failure.

is there a way to overwrite a specific type on an existing library or do I need to create a declaration file specific to my needs?

interface Json {
  success: boolean;
  data: any[];
}

type Send<T = Response> = (body?: Json) => T;

interface CustomResponse extends Response {
  json: Send<this>;
}

I was able to create a new interface that extended this. just needed to learn a bit more :) hopefully this can help out someone else!