Typescript Extend Third-party Declaration Files

How can I extend third-party declaration files? for example, I want to extend Context from @types/koa and add an extra field(resource) to it. I tried this: // global.d.ts declare n

Solution 1:

You have to use module augmentation as described here:

import { Context } from "koa";

declare module "koa" {
    interface Context {
        resource: any;
    }
}