import Vue from "../index"; declare module "../vue" { // add instance property and method interface Vue { $instanceProperty: string; $instanceMethod(): void; } // add static property and method interface VueConstructor { staticProperty: string; staticMethod(): void; } } // augment ComponentOptions declare module "../options" { interface ComponentOptions { foo?: string; } } const vm = new Vue({ props: ["bar"], data: { a: true }, foo: "foo", methods: { foo() { this.a = false; } }, computed: { BAR(): string { return this.bar.toUpperCase(); } } }); vm.$instanceProperty; vm.$instanceMethod(); Vue.staticProperty; Vue.staticMethod();