Property 'isAuth' does not exist on type 'Request<ParamsDictionary, any, any, ParsedQs>' code example

Example: Property 'isAuth' does not exist on type 'Request'

// create file custom.d.ts and declare the following

declare namespace Express {
  export interface Request {
      user: any;
  }
  export interface Response {
      user: any;
  }
}