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Signature Mismatch in `MiddlewareInterface`

See original GitHub issue

Consider the following code (note the Request/Response type hints):

export class MyMiddleware implements MiddlewareInterface {
    use(request: Request, response: Response, next?: Function): any {

Compiling throws the following error:

error TS2420: Class 'MyMiddleware' incorrectly implements interface 'MiddlewareInterface'.
  Types of property 'use' are incompatible.
    Type '(request: Request, response: Response, next?: Function) => any' is not assignable to type '{ (request: any, response: any, next?: (err?: any) => any): any; (context: any, next: (err?: any)...'.
      Types of parameters 'response' and 'next' are incompatible.
        Type '(err?: any) => Promise<any>' is not assignable to type 'Response'.
          Property 'status' is missing in type '(err?: any) => Promise<any>'.

This, however, works:

export class MyMiddleware implements MiddlewareInterface {
    use(request: any, response: any, next?: Function): any {

I tracked the issue to the second (Koa) signature in MiddlewareInterface (removing it fixes the above but, obviously, won’t make Koa happy). It looks like my code makes the TypeScript compiler think I’m trying to implement the second signature.

While I tried changing/adding signatures in MiddlewareInterface, I couldn’t get it to compile.