import Vue = require("../index"); declare module "../vue" { // add instance property and method interface Vue { $instanceProperty: string; $instanceMethod(): void; } // add static property and method namespace Vue { const staticProperty: string; function staticMethod(): void; } } // augment ComponentOptions declare module "../options" { interface ComponentOptions { foo?: string; } } const vm = new Vue({ data: { a: true }, foo: "foo" }); vm.$instanceProperty; vm.$instanceMethod(); Vue.staticProperty; Vue.staticMethod();