Merge interface from namespace in module declaration file

Question

I have a javascript library which has a type definition file here: https://github.com/tyranid-org/tyranid/blob/master/tyranid.d.ts which is exposed via the typings

Answer 1

The following ended up working...

in node_modules/tyranid/tyranid.d.ts:

export = Tyr // must do "import * as Tyr from 'tyranid'" instead of default

declare namespace Tyr {
  export interface Document {
    // original definition...
  }
}

in mylib/tyranid-extensions.d.ts...

declare module "tyranid" {
  interface Document {
    addedMethod(): boolean; 
  }
}

Thanks @pelle-jacobs for the help!